Merge branch 'e-kwsm-tautologically-false'

Add python3 to the list of badShells

.compile_binaries

@@ -1,82 +0,0 @@
-#!/bin/bash
-
-_cleanup(){
-  rm -rf dist shellcheck || true
-}
-
-build_linux() {
-  # Linux Docker image
-  name="$DOCKER_BASE"
-  DOCKER_BUILDS="$DOCKER_BUILDS $name"
-  docker build -t "$name:current" .
-  docker run "$name:current" --version
-  printf '%s\n' "#!/bin/sh" "echo 'hello world'" > myscript
-  docker run -v "$PWD:/mnt" "$name:current" myscript
-
-  # Copy static executable from docker image
-  id=$(docker create "$name:current")
-  docker cp "$id:/bin/shellcheck" "shellcheck"
-  docker rm "$id"
-  ls -l shellcheck
-  ./shellcheck myscript
-  for tag in $TAGS
-  do 
-    cp "shellcheck" "deploy/shellcheck-$tag.linux-x86_64"; 
-  done
-
-  # Linux Alpine based Docker image
-  name="$DOCKER_BASE-alpine"
-  DOCKER_BUILDS="$DOCKER_BUILDS $name"
-  sed -e '/DELETE-MARKER/,$d' Dockerfile > Dockerfile.alpine
-  docker build -f Dockerfile.alpine -t "$name:current" .
-  docker run "$name:current" sh -c 'shellcheck --version'
-  _cleanup
-}
-
-build_aarch64() {
-  # Linux aarch64 static executable
-  docker run -v "$PWD:/mnt" koalaman/aarch64-builder 'buildsc'
-  for tag in $TAGS
-  do
-    cp "shellcheck" "deploy/shellcheck-$tag.linux-aarch64"
-  done
-}
-
-
-build_armv6hf() {
-  # Linux armv6hf static executable
-  docker run -v "$PWD:/mnt" koalaman/armv6hf-builder -c 'compile-shellcheck'
-  for tag in $TAGS
-  do 
-    cp "shellcheck" "deploy/shellcheck-$tag.linux-armv6hf"; 
-  done
-  _cleanup
-}
-
-build_windows() {
-  # Windows .exe
-  docker run --user="$UID" -v "$PWD:/appdata" koalaman/winghc cuib
-  for tag in $TAGS
-  do 
-    cp "dist/build/ShellCheck/shellcheck.exe" "deploy/shellcheck-$tag.exe"; 
-  done
-  _cleanup
-}
-
-build_osx() {
-  # Darwin x86_64 static executable
-  brew install cabal-install pandoc gnu-tar
-  sudo ln -s /usr/local/bin/gsha512sum /usr/local/bin/sha512sum
-  sudo ln -s /usr/local/bin/gtar /usr/local/bin/tar
-  export PATH="/usr/local/bin:$PATH"
-
-  cabal update
-  cabal install --dependencies-only
-  cabal build shellcheck
-  for tag in $TAGS
-  do 
-    cp "dist/build/shellcheck/shellcheck" "deploy/shellcheck-$tag.darwin-x86_64";
-  done
-  _cleanup
-}
-

.github/ISSUE_TEMPLATE.md

@@ -2,10 +2,10 @@
 - Rule Id (if any, e.g. SC1000):
 - My shellcheck version (`shellcheck --version` or "online"):
 - [ ] The rule's wiki page does not already cover this (e.g. https://shellcheck.net/wiki/SC2086)
-- [ ] I tried on shellcheck.net and verified that this is still a problem on the latest commit
+- [ ] I tried on https://www.shellcheck.net/ and verified that this is still a problem on the latest commit
 
 #### For new checks and feature suggestions
-- [ ] shellcheck.net (i.e. the latest commit) currently gives no useful warnings about this
+- [ ] https://www.shellcheck.net/ (i.e. the latest commit) currently gives no useful warnings about this
 - [ ] I searched through https://github.com/koalaman/shellcheck/issues and didn't find anything related
 
 

.github/dependabot.yml

@@ -0,0 +1,7 @@
+version: 2
+
+updates:
+  - package-ecosystem: "github-actions"
+    directory: "/"
+    schedule:
+      interval: "daily"

.github/workflows/build.yml

@@ -0,0 +1,159 @@
+name: Build ShellCheck
+
+# Run this workflow every time a new commit pushed to your repository
+on: push
+
+jobs:
+  package_source:
+    name: Package Source Code
+    runs-on: ubuntu-latest
+    steps:
+      - name: Install Dependencies
+        run: |
+          sudo apt-get update
+          sudo apt-mark manual ghc # Don't bother installing ghc just to tar up source
+          sudo apt-get install cabal-install
+
+      - name: Checkout repository
+        uses: actions/checkout@v4
+        with:
+          fetch-depth: 0
+
+      - name: Deduce tags
+        run: |
+          mkdir source
+          echo "latest" > source/tags
+          if tag=$(git describe --exact-match --tags)
+          then
+            echo "stable" >> source/tags
+            echo "$tag" >> source/tags
+          fi
+          cat source/tags
+
+      - name: Package Source
+        run: |
+          grep "stable" source/tags || ./setgitversion
+          cabal sdist
+          mv dist-newstyle/sdist/*.tar.gz source/source.tar.gz
+
+      - name: Upload artifact
+        uses: actions/upload-artifact@v4
+        with:
+          name: source
+          path: source/
+
+  run_tests:
+    name: Run tests
+    needs: package_source
+    runs-on: ubuntu-latest
+    steps:
+      - name: Download artifacts
+        uses: actions/download-artifact@v4
+
+      - name: Install dependencies
+        run: |
+          sudo apt-get update && sudo apt-get install ghc cabal-install
+          cabal update
+
+      - name: Unpack source
+        run: |
+          cd source
+          tar xvf source.tar.gz --strip-components=1
+
+      - name: Build and run tests
+        run: |
+          cd source
+          cabal test
+
+  build_source:
+    name: Build
+    needs: package_source
+    strategy:
+      matrix:
+        build: [linux.x86_64, linux.aarch64, linux.armv6hf, linux.riscv64, darwin.x86_64, darwin.aarch64, windows.x86_64]
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@v4
+
+      - name: Download artifacts
+        uses: actions/download-artifact@v4
+
+      - name: Build source
+        run: |
+          mkdir -p bin
+          mkdir -p bin/${{matrix.build}}
+          ( cd bin && ../build/run_builder ../source/source.tar.gz ../build/${{matrix.build}} )
+
+      - name: Upload artifact
+        uses: actions/upload-artifact@v4
+        with:
+          name: ${{matrix.build}}.bin
+          path: bin/
+
+  package_binary:
+    name: Package Binaries
+    needs: build_source
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@v4
+
+      - name: Download artifacts
+        uses: actions/download-artifact@v4
+
+      - name: Work around GitHub permissions bug
+        run: chmod +x *.bin/*/shellcheck*
+
+      - name: Package binaries
+        run: |
+          export TAGS="$(cat source/tags)"
+          mkdir -p deploy
+          cp -r *.bin/* deploy
+          cd deploy
+          ../.prepare_deploy
+          rm -rf */ README* LICENSE*
+
+      - name: Upload artifact
+        uses: actions/upload-artifact@v4
+        with:
+          name: deploy
+          path: deploy/
+
+  deploy:
+    name: Deploy binaries
+    needs: package_binary
+    runs-on: ubuntu-latest
+    environment: Deploy
+    steps:
+      - name: Install Dependencies
+        run: |
+          sudo apt-get update
+          sudo apt-get install hub
+
+      - name: Checkout repository
+        uses: actions/checkout@v4
+
+      - name: Download artifacts
+        uses: actions/download-artifact@v4
+
+      - name: Upload to GitHub
+        env:
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+        run: |
+          export TAGS="$(cat source/tags)"
+          ./.github_deploy
+
+      - name: Waiting for GitHub to replicate uploaded releases
+        run: |
+          sleep 300
+
+      - name: Upload to Docker Hub
+        env:
+          DOCKER_USERNAME: ${{ secrets.DOCKER_USERNAME }}
+          DOCKER_PASSWORD: ${{ secrets.DOCKER_PASSWORD }}
+          DOCKER_EMAIL: ${{ secrets.DOCKER_EMAIL }}
+          DOCKER_BASE: ${{ secrets.DOCKER_USERNAME }}/shellcheck
+        run: |
+          export TAGS="$(cat source/tags)"
+          ( source ./.multi_arch_docker && set -eux && multi_arch_docker::main )

.github_deploy

@@ -0,0 +1,28 @@
+#!/bin/bash
+set -x
+shopt -s extglob
+
+export EDITOR="touch"
+
+# Sanity check
+gh --version || exit 1
+hub release show latest || exit 1
+
+for tag in $TAGS
+do
+  if ! hub release show "$tag"
+  then
+    echo "Creating new release $tag"
+    git show --no-patch  --format='format:%B' > description
+    hub release create -F description "$tag"
+  fi
+
+  files=()
+  for file in deploy/*
+  do
+    [[ $file == *.@(xz|gz|zip) ]] || continue
+    [[ $file == *"$tag"* ]] || continue
+    files+=("$file")
+  done
+  gh release upload "$tag" "${files[@]}" --clobber || exit 1
+done

.gitignore

@@ -20,3 +20,4 @@ cabal.config
 /parts/
 /prime/
 *.snap
+/dist-newstyle/

.multi_arch_docker

@@ -0,0 +1,89 @@
+#!/bin/bash
+# This script builds and deploys multi-architecture docker images from the
+# binaries previously built and deployed to GitHub.
+
+function multi_arch_docker::install_docker_buildx() {
+  # Install QEMU multi-architecture support for docker buildx.
+  docker run --rm --privileged multiarch/qemu-user-static --reset -p yes
+
+  # Instantiate docker buildx builder with multi-architecture support.
+  docker buildx create --name mybuilder
+  docker buildx use mybuilder
+  # Start up buildx and verify that all is OK.
+  docker buildx inspect --bootstrap
+}
+
+# Log in to Docker Hub for deployment.
+function multi_arch_docker::login_to_docker_hub() {
+  echo "$DOCKER_PASSWORD" | docker login -u="$DOCKER_USERNAME" --password-stdin
+}
+
+# Run buildx build and push. Passed in arguments augment the command line.
+function multi_arch_docker::buildx() {
+  mkdir -p /tmp/empty
+  docker buildx build \
+    --platform "${DOCKER_PLATFORMS// /,}" \
+    --push \
+    --progress plain \
+    -f Dockerfile.multi-arch \
+    "$@" \
+    /tmp/empty
+  rmdir /tmp/empty
+}
+
+# Build and push plain and alpine docker images for all tags.
+function multi_arch_docker::build_and_push_all() {
+  for tag in $TAGS; do
+    multi_arch_docker::buildx -t "$DOCKER_BASE:$tag" --build-arg "tag=$tag"
+    multi_arch_docker::buildx -t "$DOCKER_BASE-alpine:$tag" \
+      --build-arg "tag=$tag" --target alpine
+  done
+}
+
+# Test all pushed docker images.
+function multi_arch_docker::test_all() {
+  printf '%s\n' "#!/bin/sh" "echo 'hello world'" > myscript
+
+  for platform in $DOCKER_PLATFORMS; do
+    for tag in $TAGS; do
+      for ext in '-alpine' ''; do
+        image="${DOCKER_BASE}${ext}:${tag}"
+        msg="Testing docker image $image on platform $platform"
+        line="${msg//?/=}"
+        printf '\n%s\n%s\n%s\n' "${line}" "${msg}" "${line}"
+        docker pull -q --platform "$platform" "$image"
+        if [ -n "$ext" ]; then
+          echo -n "Image architecture: "
+          docker run --rm --entrypoint /bin/sh "$image" -c 'uname -m'
+          version=$(docker run --rm "$image" shellcheck --version \
+            | grep 'version:')
+        else
+          version=$(docker run --rm "$image" --version | grep 'version:')
+        fi
+        version=${version/#version: /v}
+        echo "shellcheck version: $version"
+        if [[ ! ("$tag" =~ ^(latest|stable)$) && "$tag" != "$version" ]]; then
+          echo "Version mismatch: shellcheck $version tagged as $tag"
+          exit 1
+        fi
+        if [ -n "$ext" ]; then
+          docker run --rm -v "$PWD:/mnt" -w /mnt "$image" shellcheck myscript
+        else
+          docker run --rm -v "$PWD:/mnt" "$image" myscript
+        fi
+      done
+    done
+  done
+}
+
+function multi_arch_docker::main() {
+  export DOCKER_PLATFORMS='linux/amd64'
+  DOCKER_PLATFORMS+=' linux/arm64'
+  DOCKER_PLATFORMS+=' linux/arm/v6'
+  DOCKER_PLATFORMS+=' linux/riscv64'
+
+  multi_arch_docker::install_docker_buildx
+  multi_arch_docker::login_to_docker_hub
+  multi_arch_docker::build_and_push_all
+  multi_arch_docker::test_all
+}

.prepare_deploy

@@ -1,8 +1,9 @@
 #!/bin/bash
-# This script packages up Travis compiled binaries
+# This script packages up compiled binaries
 set -ex
-shopt -s nullglob
-cd deploy
+shopt -s nullglob extglob
+
+ls -l
 
 cp ../LICENSE LICENSE.txt
 sed -e $'s/$/\r/' > README.txt << END
@@ -22,44 +23,32 @@ This binary was compiled on $(date -u).
 $(git log -n 3)
 END
 
-for file in ./*.exe
+for dir in */
 do
-  zip "${file%.*}.zip" README.txt LICENSE.txt "$file"
+  cp LICENSE.txt README.txt "$dir"
 done
 
-for file in *.linux-x86_64
+echo "Tags are $TAGS"
+
+for tag in $TAGS
 do
-  base="${file%.*}"
-  cp "$file" "shellcheck"
-  tar -cJf "$base.linux.x86_64.tar.xz" --transform="s:^:$base/:" README.txt LICENSE.txt shellcheck
-  rm "shellcheck"
+
+  for dir in windows.*/
+  do
+    ( cd "$dir" && zip "../shellcheck-$tag.zip" * )
   done
 
-for file in *.linux-aarch64
+  for dir in {linux,darwin}.*/
   do
-  base="${file%.*}"
-  cp "$file" "shellcheck"
-  tar -cJf "$base.linux.aarch64.tar.xz" --transform="s:^:$base/:" README.txt LICENSE.txt shellcheck
-  rm "shellcheck"
+    base="${dir%/}"
+    ( cd "$dir" && tar -cJf "../shellcheck-$tag.$base.tar.xz" --transform="s:^:shellcheck-$tag/:" * )
   done
-
-for file in *.linux-armv6hf
-do
-  base="${file%.*}"
-  cp "$file" "shellcheck"
-  tar -cJf "$base.linux.armv6hf.tar.xz" --transform="s:^:$base/:" README.txt LICENSE.txt shellcheck
-  rm "shellcheck"
-done
-
-for file in *.darwin-x86_64
-do
-  base="${file%.*}"
-  cp "$file" "shellcheck"
-  tar -cJf "$base.darwin.x86_64.tar.xz" --transform="s:^:$base/:" README.txt LICENSE.txt shellcheck
-  rm "shellcheck"
 done
 
 for file in ./*
 do
+  [[ -f "$file" ]] || continue
   sha512sum "$file" > "$file.sha512sum"
 done
+
+ls -l

.snapsquid.conf

@@ -1,14 +0,0 @@
-# In 2015, cabal-install had a http bug triggered when proxies didn't keep
-# the connection open. This version made it into Ubuntu Xenial as used by
-# Snapcraft. In June 2018, Snapcraft's proxy started triggering this bug.
-#
-#     https://bugs.launchpad.net/launchpad-buildd/+bug/1797809
-#
-# Workaround: add more proxy
-
-visible_hostname localhost
-http_port 8888
-cache_peer 10.10.10.1 parent 8222 0 no-query default
-cache_peer_domain localhost !.internal
-http_access allow all
-

.travis.yml

@@ -1,66 +0,0 @@
-
-sudo: required
-
-language: sh
-
-services:
-  - docker
-
-matrix:
-  include:
-    - os: linux
-      env: BUILD=linux
-    - os: linux
-      env: BUILD=windows
-    - os: linux
-      env: BUILD=armv6hf
-    - os: linux
-      env: BUILD=aarch64
-    - os: osx
-      env: BUILD=osx
-
-before_install: |
-  DOCKER_BASE="$DOCKER_USERNAME/shellcheck"
-  DOCKER_BUILDS=""
-  TAGS=""
-  test "$TRAVIS_BRANCH" = master && TAGS="$TAGS latest" || true
-  test -n "$TRAVIS_TAG"          && TAGS="$TAGS stable $TRAVIS_TAG" || true
-  echo "Tags are $TAGS"
-
-script:
-  - mkdir -p deploy
-  - source ./.compile_binaries
-  - ./striptests
-  - set -x; build_"$BUILD"; set +x;
-  - ./.prepare_deploy
-
-after_success: |
-  if [ "$BUILD" = "linux" ]; then
-    docker login -u="$DOCKER_USERNAME" -p="$DOCKER_PASSWORD"
-    for repo in $DOCKER_BUILDS; do
-      for tag in $TAGS; do
-        echo "Deploying $repo:current as $repo:$tag...";
-        docker tag "$repo:current" "$repo:$tag" || exit 1;
-        docker push "$repo:$tag" || exit 1;
-      done;
-    done;
-  fi
-
-after_failure: |
-  id
-  pwd
-  df -h
-  find . -name '*.log' -type f -exec grep "" /dev/null {} +
-  find . -ls
-
-deploy:
-  provider: gcs
-  skip_cleanup: true
-  access_key_id: GOOG7MDN7WEH6IIGBDCA
-  secret_access_key:
-    secure: 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
-  bucket: shellcheck
-  local-dir: deploy
-  on:
-    repo: koalaman/shellcheck
-    all_branches: true

CHANGELOG.md

@@ -1,3 +1,156 @@
+## Git
+### Added
+- SC2327/SC2328: Warn about capturing the output of redirected commands.
+- SC2329: Warn when (non-escaping) functions are never invoked.
+- SC2330: Warn about unsupported glob matches with [[ .. ]] in BusyBox.
+- SC2331: Suggest using standard -e instead of unary -a in tests.
+- SC2332: Warn about `[ ! -o opt ]` being unconditionally true in Bash.
+- SC3062: Warn about bashism `[ -o opt ]`.
+- Precompiled binaries for Linux riscv64 (linux.riscv64)
+### Changed
+- SC2002 about Useless Use Of Cat is now disabled by default. It can be
+  re-enabled with `--enable=useless-use-of-cat` or equivalent directive.
+- SC2015 about `A && B || C` no longer triggers when B is a test command.
+- SC3012: Do not warn about `\<` and `\>` in test/[] as specified in POSIX.1-2024
+### Fixed
+- SC2218 about function use-before-define is now more accurate.
+- SC2317 about unreachable commands is now less spammy for nested ones.
+- SC2292, optional suggestion for [[ ]], now triggers for Busybox.
+
+### Removed
+- SC3013: removed since the operators `-ot/-nt/-ef` are specified in POSIX.1-2024
+
+## v0.10.0 - 2024-03-07
+### Added
+- Precompiled binaries for macOS ARM64 (darwin.aarch64)
+- Added support for busybox sh
+- Added flag --rcfile to specify an rc file by name.
+- Added `extended-analysis=true` directive to enable/disable dataflow analysis
+  (with a corresponding --extended-analysis flag).
+- SC2324: Warn when x+=1 appends instead of increments
+- SC2325: Warn about multiple `!`s in dash/sh.
+- SC2326: Warn about `foo | ! bar` in bash/dash/sh.
+- SC3012: Warn about lexicographic-compare bashism in test like in [ ]
+- SC3013: Warn bashism `test _ -op/-nt/-ef _` like in [ ]
+- SC3014: Warn bashism `test _ == _` like in [ ]
+- SC3015: Warn bashism `test _ =~ _` like in [ ]
+- SC3016: Warn bashism `test -v _` like in [ ]
+- SC3017: Warn bashism `test -a _` like in [ ]
+
+### Fixed
+- source statements with here docs now work correctly
+- "(Array.!): undefined array element" error should no longer occur
+
+
+## v0.9.0 - 2022-12-12
+### Added
+- SC2316: Warn about 'local readonly foo' and similar (thanks, patrickxia!)
+- SC2317: Warn about unreachable commands
+- SC2318: Warn about backreferences in 'declare x=1 y=$x'
+- SC2319/SC2320: Warn when $? refers to echo/printf/[ ]/[[ ]]/test
+- SC2321: Suggest removing $((..)) in array[$((idx))]=val
+- SC2322: Suggest collapsing double parentheses in arithmetic contexts
+- SC2323: Suggest removing wrapping parentheses in a[(x+1)]=val
+
+### Fixed
+- SC2086: Now uses DFA to make more accurate predictions about values
+- SC2086: No longer warns about values declared as integer with declare -i
+
+### Changed
+- ShellCheck now has a Data Flow Analysis engine to make smarter decisions
+  based on control flow rather than just syntax. Existing checks will
+  gradually start using it, which may cause them to trigger differently
+  (but more accurately).
+- Values in directives/shellcheckrc can now be quoted with '' or ""
+
+
+## v0.8.0 - 2021-11-06
+### Added
+- `disable=all` now conveniently disables all warnings
+- `external-sources=true` directive can be added to .shellcheckrc to make
+  shellcheck behave as if `-x` was specified.
+- Optional `check-extra-masked-returns` for pointing out commands with
+  suppressed exit codes (SC2312).
+- Optional `require-double-brackets` for recommending \[\[ ]] (SC2292).
+- SC2286-SC2288: Warn when command name ends in a symbol like `/.)'"`
+- SC2289: Warn when command name contains tabs or linefeeds
+- SC2291: Warn about repeated unquoted spaces between words in echo
+- SC2292: Suggest [[ over [ in Bash/Ksh scripts (optional)
+- SC2293/SC2294: Warn when calling `eval` with arrays
+- SC2295: Warn about "${x#$y}" treating $y as a pattern when not quoted
+- SC2296-SC2301: Improved warnings for bad parameter expansions
+- SC2302/SC2303: Warn about loops over array values when using them as keys
+- SC2304-SC2306: Warn about unquoted globs in expr arguments
+- SC2307: Warn about insufficient number of arguments to expr
+- SC2308: Suggest other approaches for non-standard expr extensions
+- SC2313: Warn about `read` with unquoted, array indexed variable
+
+### Fixed
+- SC2102 about repetitions in ranges no longer triggers on [[ -v arr[xx] ]]
+- SC2155 now recognizes `typeset` and local read-only `declare` statements
+- SC2181 now tries to avoid triggering for error handling functions
+- SC2290: Warn about misused = in declare & co, which were not caught by SC2270+
+- The flag --color=auto no longer outputs color when TERM is "dumb" or unset
+
+### Changed
+- SC2048: Warning about $\* now also applies to ${array[\*]}
+- SC2181 now only triggers on single condition tests like `[ $? = 0 ]`.
+- Quote warnings are now emitted for declaration utilities in sh
+- Leading `_` can now be used to suppress warnings about unused variables
+- TTY output now includes warning level in text as well as color
+
+### Removed
+- SC1004: Literal backslash+linefeed in '' was found to be usually correct
+
+
+## v0.7.2 - 2021-04-19
+### Added
+- `disable` directives can now be a range, e.g. `disable=SC3000-SC4000`
+- SC1143: Warn about line continuations in comments
+- SC2259/SC2260: Warn when redirections override pipes
+- SC2261: Warn about multiple competing redirections
+- SC2262/SC2263: Warn about aliases declared and used in the same parsing unit
+- SC2264: Warn about wrapper functions that blatantly recurse
+- SC2265/SC2266: Warn when using & or | with test statements
+- SC2267: Warn when using xargs -i instead of -I
+- SC2268: Warn about unnecessary x-comparisons like `[ x$var = xval ]`
+
+### Fixed
+- SC1072/SC1073 now respond to disable annotations, though ignoring parse errors
+  is still purely cosmetic and does not allow ShellCheck to continue.
+- Improved error reporting for trailing tokens after ]/]] and compound commands
+- `#!/usr/bin/env -S shell` is now handled correctly
+- Here docs with \r are now parsed correctly and give better warnings
+
+### Changed
+- Assignments are now parsed to spec, without leniency for leading $ or spaces
+- POSIX/dash unsupported feature warnings now have individual SC3xxx codes
+- SC1090: A leading `$x/` or `$(x)/` is now treated as `./` when locating files
+- SC2154: Variables appearing in -z/-n tests are no longer considered unassigned
+- SC2270-SC2285: Improved warnings about misused `=`, e.g. `${var}=42`
+
+
+## v0.7.1 - 2020-04-04
+### Fixed
+- `-f diff` no longer claims that it found more issues when it didn't
+- Known empty variables now correctly trigger SC2086
+- ShellCheck should now be compatible with Cabal 3
+- SC2154 and all command-specific checks now trigger for builtins
+  called with `builtin`
+
+### Added
+- SC1136: Warn about unexpected characters after ]/]]
+- SC2254: Suggest quoting expansions in case statements
+- SC2255: Suggest using `$((..))` in `[ 2*3 -eq 6 ]`
+- SC2256: Warn about translated strings that are known variables
+- SC2257: Warn about arithmetic mutation in redirections
+- SC2258: Warn about trailing commas in for loop elements
+
+### Changed
+- SC2230: 'command -v' suggestion is now off by default (-i deprecate-which)
+- SC1081: Keywords are now correctly parsed case sensitively, with a warning
+
+
 ## v0.7.0 - 2019-07-28
 ### Added
 - Precompiled binaries for macOS and Linux aarch64
@@ -117,7 +270,7 @@
 - SC2204/SC2205: Warn about `( -z foo )` and `( foo -eq bar )`
 - SC2200/SC2201: Warn about brace expansion in [/[[
 - SC2198/SC2199: Warn about arrays in [/[[
-- SC2196/SC2197: Warn about deprected egrep/fgrep
+- SC2196/SC2197: Warn about deprecated egrep/fgrep
 - SC2195: Warn about unmatchable case branches
 - SC2194: Warn about constant 'case' statements
 - SC2193: Warn about `[[ file.png == *.mp3 ]]` and other unmatchables
@@ -134,7 +287,7 @@
 ### Fixed
 - `-c` no longer suggested when using `grep -o | wc`
 - Comments and whitespace are now allowed before filewide directives
-- Here doc delimters with esoteric quoting like `foo""` are now handled
+- Here doc delimiters with esoteric quoting like `foo""` are now handled
 - SC2095 about `ssh` in while read loops is now suppressed when using `-n`
 - `%(%Y%M%D)T` now recognized as a single formatter in `printf` checks
 - `grep -F` now suppresses regex related suggestions

Dockerfile

@@ -1,36 +0,0 @@
-# Build-only image
-FROM ubuntu:18.04 AS build
-USER root
-WORKDIR /opt/shellCheck
-
-# Install OS deps
-RUN apt-get update && apt-get install -y ghc cabal-install
-
-# Install Haskell deps
-# (This is a separate copy/run so that source changes don't require rebuilding)
-COPY ShellCheck.cabal ./
-RUN cabal update && cabal install --dependencies-only --ghc-options="-optlo-Os -split-sections"
-
-# Copy source and build it
-COPY LICENSE Setup.hs shellcheck.hs ./
-COPY src src
-RUN cabal build Paths_ShellCheck && \
-  ghc -optl-static -optl-pthread -isrc -idist/build/autogen --make shellcheck -split-sections -optc-Wl,--gc-sections -optlo-Os && \
-  strip --strip-all shellcheck
-
-RUN mkdir -p /out/bin && \
-  cp shellcheck  /out/bin/
-
-# Resulting Alpine image
-FROM alpine:latest
-LABEL maintainer="Vidar Holen <vidar@vidarholen.net>"
-COPY --from=build /out /
-
-# DELETE-MARKER (Remove everything below to keep the alpine image)
-
-# Resulting ShellCheck image
-FROM scratch
-LABEL maintainer="Vidar Holen <vidar@vidarholen.net>"
-WORKDIR /mnt
-COPY --from=build /out /
-ENTRYPOINT ["/bin/shellcheck"]

Dockerfile.multi-arch

@@ -0,0 +1,26 @@
+# Alpine image
+FROM alpine:latest AS alpine
+LABEL maintainer="Vidar Holen <vidar@vidarholen.net>"
+ARG tag
+
+# Put the right binary for each architecture into place for the
+# multi-architecture docker image.
+RUN set -x; \
+  arch="$(uname -m)"; \
+  echo "arch is $arch"; \
+  if [ "${arch}" = 'armv7l' ]; then \
+    arch='armv6hf'; \
+  fi; \
+  url_base='https://github.com/koalaman/shellcheck/releases/download/'; \
+  tar_file="${tag}/shellcheck-${tag}.linux.${arch}.tar.xz"; \
+  wget "${url_base}${tar_file}" -O - | tar xJf -; \
+  mv "shellcheck-${tag}/shellcheck" /bin/; \
+  rm -rf "shellcheck-${tag}"; \
+  ls -laF /bin/shellcheck
+
+# ShellCheck image
+FROM scratch
+LABEL maintainer="Vidar Holen <vidar@vidarholen.net>"
+WORKDIR /mnt
+COPY --from=alpine /bin/shellcheck /bin/
+ENTRYPOINT ["/bin/shellcheck"]

LICENSE

@@ -1,13 +1,3 @@
-Employer mandated disclaimer:
-
-  I am providing code in the repository to you under an open source license.
-  Because this is my personal repository, the license you receive to my code is
-  from me and other individual contributors, and not my employer (Facebook).
-
-  - Vidar "koala_man" Holen
-
-----
-
                     GNU GENERAL PUBLIC LICENSE
                        Version 3, 29 June 2007
 
@@ -681,4 +671,4 @@ into proprietary programs.  If your program is a subroutine library, you
 may consider it more useful to permit linking proprietary applications with
 the library.  If this is what you want to do, use the GNU Lesser General
 Public License instead of this License.  But first, please read
-<https://www.gnu.org/philosophy/why-not-lgpl.html>.
+<https://www.gnu.org/licenses/why-not-lgpl.html>.

README.md

@@ -1,4 +1,5 @@
-[![Build Status](https://travis-ci.org/koalaman/shellcheck.svg?branch=master)](https://travis-ci.org/koalaman/shellcheck)
+[![Build Status](https://github.com/koalaman/shellcheck/actions/workflows/build.yml/badge.svg)](https://github.com/koalaman/shellcheck/actions/workflows/build.yml)
+
 
 # ShellCheck - A shell script static analysis tool
 
@@ -76,7 +77,7 @@ You can see ShellCheck suggestions directly in a variety of editors.
 
 * Sublime, through [SublimeLinter](https://github.com/SublimeLinter/SublimeLinter-shellcheck).
 
-* Atom, through [Linter](https://github.com/AtomLinter/linter-shellcheck).
+* Pulsar Edit (former Atom), through [linter-shellcheck-pulsar](https://github.com/pulsar-cooperative/linter-shellcheck-pulsar).
 
 * VSCode, through [vscode-shellcheck](https://github.com/timonwong/vscode-shellcheck).
 
@@ -109,14 +110,15 @@ Services and platforms that have ShellCheck pre-installed and ready to use:
 * [Codacy](https://www.codacy.com/)
 * [Code Climate](https://codeclimate.com/)
 * [Code Factor](https://www.codefactor.io/)
-
-Services and platforms with third party plugins:
-
-* [SonarQube](https://www.sonarqube.org/) through [sonar-shellcheck-plugin](https://github.com/emerald-squad/sonar-shellcheck-plugin)
+* [Codety](https://www.codety.io/) via the [Codety Scanner](https://github.com/codetyio/codety-scanner)
+* [CircleCI](https://circleci.com) via the [ShellCheck Orb](https://circleci.com/orbs/registry/orb/circleci/shellcheck)
+* [Github](https://github.com/features/actions) (only Linux)
+* [Trunk Check](https://trunk.io/products/check) (universal linter; [allows you to explicitly version your shellcheck install](https://github.com/trunk-io/plugins/blob/bcbb361dcdbe4619af51ea7db474d7fb87540d20/.trunk/trunk.yaml#L32)) via the [shellcheck plugin](https://github.com/trunk-io/plugins/blob/main/linters/shellcheck/plugin.yaml)
+* [CodeRabbit](https://coderabbit.ai/)
 
 Most other services, including [GitLab](https://about.gitlab.com/), let you install
 ShellCheck yourself, either through the system's package manager (see [Installing](#installing)),
-or by downloading and unpacking a [binary release](#installing-the-shellcheck-binary).
+or by downloading and unpacking a [binary release](#installing-a-pre-compiled-binary).
 
 It's a good idea to manually install a specific ShellCheck version regardless. This avoids
 any surprise build breaks when a new version with new warnings is published.
@@ -141,13 +143,13 @@ On systems with Stack (installs to `~/.local/bin`):
 
 On Debian based distros:
 
-    apt-get install shellcheck
+    sudo apt install shellcheck
 
 On Arch Linux based distros:
 
     pacman -S shellcheck
 
-or get the dependency free [shellcheck-static](https://aur.archlinux.org/packages/shellcheck-static/) from the AUR.
+or get the dependency free [shellcheck-bin](https://aur.archlinux.org/packages/shellcheck-bin/) from the AUR.
 
 On Gentoo based distros:
 
@@ -155,8 +157,8 @@ On Gentoo based distros:
 
 On EPEL based distros:
 
-    yum -y install epel-release
-    yum install ShellCheck
+    sudo yum -y install epel-release
+    sudo yum install ShellCheck
 
 On Fedora based distros:
 
@@ -166,10 +168,14 @@ On FreeBSD:
 
     pkg install hs-ShellCheck
 
-On OS X with homebrew:
+On macOS (OS X) with Homebrew:
 
     brew install shellcheck
 
+Or with MacPorts:
+
+    sudo port install shellcheck
+
 On OpenBSD:
 
     pkg_add shellcheck
@@ -190,12 +196,22 @@ On Windows (via [chocolatey](https://chocolatey.org/packages/shellcheck)):
 C:\> choco install shellcheck
 ```
 
+Or Windows (via [winget](https://github.com/microsoft/winget-pkgs)):
+
+```cmd
+C:\> winget install --id koalaman.shellcheck
+```
+
 Or Windows (via [scoop](http://scoop.sh)):
 
 ```cmd
 C:\> scoop install shellcheck
 ```
 
+From [conda-forge](https://anaconda.org/conda-forge/shellcheck):
+
+    conda install -c conda-forge shellcheck
+
 From Snap Store:
 
     snap install --channel=edge shellcheck
@@ -209,15 +225,30 @@ docker run --rm -v "$PWD:/mnt" koalaman/shellcheck:stable myscript
 
 or use `koalaman/shellcheck-alpine` if you want a larger Alpine Linux based image to extend. It works exactly like a regular Alpine image, but has shellcheck preinstalled.
 
+Using the [nix package manager](https://nixos.org/nix):
+```sh
+nix-env -iA nixpkgs.shellcheck
+```
+
+Using the [Flox package manager](https://flox.dev/)
+```sh
+flox install shellcheck
+```
+
 Alternatively, you can download pre-compiled binaries for the latest release here:
 
-* [Linux, x86_64](https://storage.googleapis.com/shellcheck/shellcheck-stable.linux.x86_64.tar.xz) (statically linked)
-* [Linux, armv6hf](https://storage.googleapis.com/shellcheck/shellcheck-stable.linux.armv6hf.tar.xz), i.e. Raspberry Pi (statically linked)
-* [Linux, aarch64](https://storage.googleapis.com/shellcheck/shellcheck-stable.linux.armv6hf.tar.xz) aka ARM64 (statically linked)
-* [MacOS, x86_64](https://shellcheck.storage.googleapis.com/shellcheck-stable.darwin.x86_64.tar.xz)
-* [Windows, x86](https://storage.googleapis.com/shellcheck/shellcheck-stable.zip)
+* [Linux, x86_64](https://github.com/koalaman/shellcheck/releases/download/stable/shellcheck-stable.linux.x86_64.tar.xz) (statically linked)
+* [Linux, armv6hf](https://github.com/koalaman/shellcheck/releases/download/stable/shellcheck-stable.linux.armv6hf.tar.xz), i.e. Raspberry Pi (statically linked)
+* [Linux, aarch64](https://github.com/koalaman/shellcheck/releases/download/stable/shellcheck-stable.linux.aarch64.tar.xz) aka ARM64 (statically linked)
+* [macOS, aarch64](https://github.com/koalaman/shellcheck/releases/download/stable/shellcheck-stable.darwin.aarch64.tar.xz)
+* [macOS, x86_64](https://github.com/koalaman/shellcheck/releases/download/stable/shellcheck-stable.darwin.x86_64.tar.xz)
+* [Windows, x86](https://github.com/koalaman/shellcheck/releases/download/stable/shellcheck-stable.zip)
 
-or see the [storage bucket listing](https://shellcheck.storage.googleapis.com/index.html) for checksums, older versions and the latest daily builds.
+or see the [GitHub Releases](https://github.com/koalaman/shellcheck/releases) for other releases
+(including the [latest](https://github.com/koalaman/shellcheck/releases/tag/latest) meta-release for daily git builds).
+
+There are currently no official binaries for Apple Silicon, but third party builds are available via
+[ShellCheck for Visual Studio Code](https://github.com/vscode-shellcheck/shellcheck-binaries/releases).
 
 Distro packages already come with a `man` page. If you are building from source, it can be installed with:
 
@@ -226,6 +257,19 @@ pandoc -s -f markdown-smart -t man shellcheck.1.md -o shellcheck.1
 sudo mv shellcheck.1 /usr/share/man/man1
 ```
 
+### pre-commit
+
+To run ShellCheck via [pre-commit](https://pre-commit.com/), add the hook to your `.pre-commit-config.yaml`:
+
+```
+repos:
+-   repo: https://github.com/koalaman/shellcheck-precommit
+    rev: v0.7.2
+    hooks:
+    -   id: shellcheck
+#       args: ["--severity=warning"]  # Optionally only show errors and warnings
+```
+
 ### Travis CI
 
 Travis CI has now integrated ShellCheck by default, so you don't need to manually install it.
@@ -244,7 +288,7 @@ A simple installer may do something like:
 
 ```bash
 scversion="stable" # or "v0.4.7", or "latest"
-wget -qO- "https://storage.googleapis.com/shellcheck/shellcheck-${scversion?}.linux.x86_64.tar.xz" | tar -xJv
+wget -qO- "https://github.com/koalaman/shellcheck/releases/download/${scversion?}/shellcheck-${scversion?}.linux.x86_64.tar.xz" | tar -xJv
 cp "shellcheck-${scversion}/shellcheck" /usr/bin/
 shellcheck --version
 ```
@@ -257,7 +301,7 @@ This section describes how to build ShellCheck from a source directory. ShellChe
 
 ShellCheck is built and packaged using Cabal. Install the package `cabal-install` from your system's package manager (with e.g. `apt-get`, `brew`, `emerge`, `yum`, or `zypper`).
 
-On MacOS (OS X), you can do a fast install of Cabal using brew, which takes a couple of minutes instead of more than 30 minutes if you try to compile it from source.
+On macOS (OS X), you can do a fast install of Cabal using brew, which takes a couple of minutes instead of more than 30 minutes if you try to compile it from source.
 
     $ brew install cabal-install
 
@@ -273,10 +317,6 @@ Verify that `cabal` is installed and update its dependency list with
 
     $ cabal install
 
-Or if you intend to run the tests:
-
-    $ cabal install --enable-tests
-
 This will compile ShellCheck and install it to your `~/.cabal/bin` directory.
 
 Add this directory to your `PATH` (for bash, add this to your `~/.bashrc`):
@@ -332,6 +372,7 @@ echo 'Don't forget to restart!'   # Singlequote closed by apostrophe
 echo 'Don\'t try this at home'    # Attempting to escape ' in ''
 echo 'Path is $PATH'              # Variables in single quotes
 trap "echo Took ${SECONDS}s" 0    # Prematurely expanded trap
+unset var[i]                      # Array index treated as glob
 ```
 
 ### Conditionals
@@ -350,6 +391,7 @@ ShellCheck can recognize many types of incorrect test statements.
 [ grep -q foo file ]              # Command without $(..)
 [[ "$$file" == *.jpg ]]           # Comparisons that can't succeed
 (( 1 -lt 2 ))                     # Using test operators in ((..))
+[ x ] & [ y ] | [ z ]             # Accidental backgrounding and piping
 ```
 
 ### Frequently misused commands
@@ -421,6 +463,8 @@ echo "Hello $name"                # Unassigned lowercase variables
 cmd | read bar; echo $bar         # Assignments in subshells
 cat foo | cp bar                  # Piping to commands that don't read
 printf '%s: %s\n' foo             # Mismatches in printf argument count
+eval "${array[@]}"                # Lost word boundaries in array eval
+for i in "${x[@]}"; do ${x[$i]}   # Using array value as key
 ```
 
 ### Robustness
@@ -445,6 +489,7 @@ ShellCheck will warn when using features not supported by the shebang. For examp
 echo {1..$n}                     # Works in ksh, but not bash/dash/sh
 echo {1..10}                     # Works in ksh and bash, but not dash/sh
 echo -n 42                       # Works in ksh, bash and dash, undefined in sh
+expr match str regex             # Unportable alias for `expr str : regex`
 trap 'exit 42' sigint            # Unportable signal spec
 cmd &> file                      # Unportable redirection operator
 read foo < /dev/tcp/host/22      # Unportable intercepted files
@@ -465,10 +510,15 @@ rm “file”                         # Unicode quotes
 echo "Hello world"                # Carriage return / DOS line endings
 echo hello \                      # Trailing spaces after \
 var=42 echo $var                  # Expansion of inlined environment
-#!/bin/bash -x -e                 # Common shebang errors
+!# bin/bash -x -e                 # Common shebang errors
 echo $((n/180*100))               # Unnecessary loss of precision
 ls *[:digit:].txt                 # Bad character class globs
 sed 's/foo/bar/' file > file      # Redirecting to input
+var2=$var2                        # Variable assigned to itself
+[ x$var = xval ]                  # Antiquated x-comparisons
+ls() { ls -l "$@"; }              # Infinitely recursive wrapper
+alias ls='ls -l'; ls foo          # Alias used before it takes effect
+for x; do for x; do               # Nested loop uses same variable
 while getopts "a" f; do case $f in "b") # Unhandled getopts flags
 ```
 
@@ -512,4 +562,3 @@ Happy ShellChecking!
 
 * The wiki has [long form descriptions](https://github.com/koalaman/shellcheck/wiki/Checks) for each warning, e.g. [SC2221](https://github.com/koalaman/shellcheck/wiki/SC2221).
 * ShellCheck does not attempt to enforce any kind of formatting or indenting style, so also check out [shfmt](https://github.com/mvdan/sh)!
-

Setup.hs

@@ -1,36 +0,0 @@
-import Distribution.PackageDescription (
-  HookedBuildInfo,
-  emptyHookedBuildInfo )
-import Distribution.Simple (
-  Args,
-  UserHooks ( preSDist ),
-  defaultMainWithHooks,
-  simpleUserHooks )
-import Distribution.Simple.Setup ( SDistFlags )
-
-import System.Process ( system )
-
-
-main = defaultMainWithHooks myHooks
-  where
-    myHooks = simpleUserHooks { preSDist = myPreSDist }
-
--- | This hook will be executed before e.g. @cabal sdist@. It runs
---   pandoc to create the man page from shellcheck.1.md. If the pandoc
---   command is not found, this will fail with an error message:
---
---     /bin/sh: pandoc: command not found
---
---   Since the man page is listed in the Extra-Source-Files section of
---   our cabal file, a failure here should result in a failure to
---   create the distribution tarball (that's a good thing).
---
-myPreSDist :: Args -> SDistFlags -> IO HookedBuildInfo
-myPreSDist _ _ = do
-  putStrLn "Building the man page (shellcheck.1) with pandoc..."
-  putStrLn pandoc_cmd
-  result <- system pandoc_cmd
-  putStrLn $ "pandoc exited with " ++ show result
-  return emptyHookedBuildInfo
-  where
-    pandoc_cmd = "pandoc -s -f markdown-smart -t man shellcheck.1.md -o shellcheck.1"

ShellCheck.cabal

@@ -1,5 +1,5 @@
 Name:             ShellCheck
-Version:          0.7.0
+Version:          0.10.0
 Synopsis:         Shell script analysis tool
 License:          GPL-3
 License-file:     LICENSE
@@ -7,8 +7,8 @@ Category:         Static Analysis
 Author:           Vidar Holen
 Maintainer:       vidar@vidarholen.net
 Homepage:         https://www.shellcheck.net/
-Build-Type:       Custom
-Cabal-Version:    >= 1.8
+Build-Type:       Simple
+Cabal-Version:    1.18
 Bug-reports:      https://github.com/koalaman/shellcheck/issues
 Description:
   The goals of ShellCheck are:
@@ -22,23 +22,19 @@ Description:
   * To point out subtle caveats, corner cases and pitfalls, that may cause an
     advanced user's otherwise working script to fail under future circumstances.
 
+Extra-Doc-Files:
+    README.md
+    CHANGELOG.md
 Extra-Source-Files:
     -- documentation
-    README.md
     shellcheck.1.md
-    -- built with a cabal sdist hook
-    shellcheck.1
+    -- A script to build the man page using pandoc
+    manpage
     -- convenience script for stripping tests
     striptests
     -- tests
     test/shellcheck.hs
 
-custom-setup
-  setup-depends:
-    base    >= 4    && <5,
-    process >= 1.0  && <1.7,
-    Cabal   >= 1.10 && <2.5
-
 source-repository head
     type: git
     location: git://github.com/koalaman/shellcheck.git
@@ -49,21 +45,26 @@ library
       build-depends:
         semigroups
     build-depends:
-      aeson,
-      array,
-      -- GHC 7.6.3 (base 4.6.0.1) is buggy (#1131, #1119) in optimized mode.
-      -- Just disable that version entirely to fail fast.
-      base > 4.6.0.1 && < 5,
-      bytestring,
-      containers >= 0.5,
-      deepseq >= 1.4.0.0,
-      Diff >= 0.2.0,
-      directory >= 1.2.3.0,
-      mtl >= 2.2.1,
-      filepath,
-      parsec,
-      regex-tdfa,
-      QuickCheck >= 2.7.4,
+      -- The lower bounds are based on GHC 7.10.3
+      -- The upper bounds are based on GHC 9.8.1
+      aeson                >= 1.4.0 && < 2.3,
+      array                >= 0.5.1 && < 0.6,
+      base                 >= 4.8.0.0 && < 5,
+      bytestring           >= 0.10.6 && < 0.13,
+      containers           >= 0.5.6 && < 0.8,
+      deepseq              >= 1.4.1 && < 1.6,
+      Diff                 >= 0.4.0 && < 1.1,
+      fgl                  (>= 5.7.0 && < 5.8.1.0) || (>= 5.8.1.1 && < 5.9),
+      filepath             >= 1.4.0 && < 1.6,
+      mtl                  >= 2.2.2 && < 2.4,
+      parsec               >= 3.1.14 && < 3.2,
+      QuickCheck           >= 2.14.2 && < 2.16,
+      regex-tdfa           >= 1.2.0 && < 1.4,
+      transformers         >= 0.4.2 && < 0.7,
+
+      -- getXdgDirectory from 1.2.3.0
+      directory            >= 1.2.3 && < 1.4,
+
       -- When cabal supports it, move this to setup-depends:
       process
     exposed-modules:
@@ -72,11 +73,15 @@ library
       ShellCheck.Analytics
       ShellCheck.Analyzer
       ShellCheck.AnalyzerLib
+      ShellCheck.CFG
+      ShellCheck.CFGAnalysis
       ShellCheck.Checker
       ShellCheck.Checks.Commands
+      ShellCheck.Checks.ControlFlow
       ShellCheck.Checks.Custom
       ShellCheck.Checks.ShellSupport
       ShellCheck.Data
+      ShellCheck.Debug
       ShellCheck.Fixer
       ShellCheck.Formatter.Format
       ShellCheck.Formatter.CheckStyle
@@ -88,9 +93,11 @@ library
       ShellCheck.Formatter.Quiet
       ShellCheck.Interface
       ShellCheck.Parser
+      ShellCheck.Prelude
       ShellCheck.Regex
     other-modules:
       Paths_ShellCheck
+    default-language: Haskell98
 
 executable shellcheck
     if impl(ghc < 8.0)
@@ -99,18 +106,21 @@ executable shellcheck
     build-depends:
       aeson,
       array,
-      base >= 4 && < 5,
+      base,
       bytestring,
       containers,
-      deepseq >= 1.4.0.0,
-      Diff >= 0.2.0,
-      directory >= 1.2.3.0,
-      mtl >= 2.2.1,
+      deepseq,
+      Diff,
+      directory,
+      fgl,
+      mtl,
       filepath,
-      parsec >= 3.0,
-      QuickCheck >= 2.7.4,
+      parsec,
+      QuickCheck,
       regex-tdfa,
+      transformers,
       ShellCheck
+    default-language: Haskell98
     main-is: shellcheck.hs
 
 test-suite test-shellcheck
@@ -118,17 +128,19 @@ test-suite test-shellcheck
     build-depends:
       aeson,
       array,
-      base >= 4 && < 5,
+      base,
       bytestring,
       containers,
-      deepseq >= 1.4.0.0,
-      Diff >= 0.2.0,
-      directory >= 1.2.3.0,
-      mtl >= 2.2.1,
+      deepseq,
+      Diff,
+      directory,
+      fgl,
       filepath,
+      mtl,
       parsec,
-      QuickCheck >= 2.7.4,
+      QuickCheck,
       regex-tdfa,
+      transformers,
       ShellCheck
+    default-language: Haskell98
     main-is: test/shellcheck.hs
-

build/README.md

@@ -0,0 +1,17 @@
+This directory contains Dockerfiles for all builds.
+
+A build image will:
+
+* Run on Linux x86\_64 with vanilla Docker (no exceptions)
+* Not contain any software that would restrict easy modification or copying
+* Take a `cabal sdist` style tar.gz of the ShellCheck directory on stdin
+* Output a tar.gz of artifacts on stdout, in a directory named for the arch
+
+This makes it simple to build any release without exotic hardware or software.
+
+An image can be built and tagged using `build_builder`,
+and run on a source tarball using `run_builder`.
+
+Tip: Are you developing an image that relies on QEmu usermode emulation?
+     It's easy to accidentally depend on binfmt\_misc on the host OS.
+     Do a `echo 0 | sudo tee /proc/sys/fs/binfmt_misc/status` before testing.

build/build_builder

@@ -0,0 +1,12 @@
+#!/bin/sh
+if [ $# -eq 0 ]
+then
+  echo >&2 "No build image directories specified"
+  echo >&2 "Example: $0 build/*/"
+  exit 1
+fi
+
+for dir
+do
+  ( cd "$dir" && docker build -t "$(cat tag)" . ) || exit 1
+done

build/darwin.aarch64/Dockerfile

@@ -0,0 +1,40 @@
+FROM ghcr.io/shepherdjerred/macos-cross-compiler:latest
+
+ENV TARGET aarch64-apple-darwin22
+ENV TARGETNAME darwin.aarch64
+
+# Build dependencies
+USER root
+ENV DEBIAN_FRONTEND noninteractive
+ENV LC_ALL C.utf8
+
+# Install basic deps
+RUN apt-get update && apt-get install -y automake autoconf build-essential curl xz-utils qemu-user-static
+
+# Install a more suitable host compiler
+WORKDIR /host-ghc
+RUN curl -L "https://downloads.haskell.org/~cabal/cabal-install-3.9.0.0/cabal-install-3.9-x86_64-linux-alpine.tar.xz" | tar xJv -C /usr/local/bin
+RUN curl -L 'https://downloads.haskell.org/~ghc/8.10.7/ghc-8.10.7-x86_64-deb10-linux.tar.xz' | tar xJ --strip-components=1
+RUN ./configure && make install
+
+# Build GHC. We have to use an old version because cross-compilation across OS has since broken.
+WORKDIR /ghc
+RUN curl -L "https://downloads.haskell.org/~ghc/8.10.7/ghc-8.10.7-src.tar.xz" | tar xJ --strip-components=1
+RUN apt-get install -y llvm-12
+RUN ./boot && ./configure --host x86_64-linux-gnu --build x86_64-linux-gnu --target "$TARGET"
+RUN cp mk/flavours/quick-cross.mk mk/build.mk && make -j "$(nproc)"
+RUN make install
+
+# Due to an apparent cabal bug, we specify our options directly to cabal
+# It won't reuse caches if ghc-options are specified in ~/.cabal/config
+ENV CABALOPTS "--ghc-options;-optc-Os -optc-fPIC;--with-ghc=$TARGET-ghc;--with-hc-pkg=$TARGET-ghc-pkg;--constraint=hashable==1.3.5.0"
+
+# Prebuild the dependencies
+RUN cabal update
+RUN IFS=';' && cabal install --dependencies-only $CABALOPTS ShellCheck
+
+# Copy the build script
+COPY build /usr/bin
+
+WORKDIR /scratch
+ENTRYPOINT ["/usr/bin/build"]

build/darwin.aarch64/build

@@ -0,0 +1,16 @@
+#!/bin/sh
+set -xe
+{
+  tar xzv --strip-components=1
+  chmod +x striptests && ./striptests
+  mkdir "$TARGETNAME"
+  ( IFS=';'; cabal build $CABALOPTS )
+  find . -name shellcheck -type f -exec mv {} "$TARGETNAME/" \;
+  ls -l "$TARGETNAME"
+  # Stripping invalidates the code signature and the build image does
+  # not appear to have anything similar to the 'codesign' tool.
+  # "$TARGET-strip" "$TARGETNAME/shellcheck"
+  ls -l "$TARGETNAME"
+  file "$TARGETNAME/shellcheck" | grep "Mach-O 64-bit arm64 executable"
+} >&2
+tar czv "$TARGETNAME"

build/darwin.aarch64/tag

@@ -0,0 +1 @@
+koalaman/scbuilder-darwin-aarch64

build/darwin.x86_64/Dockerfile

@@ -0,0 +1,33 @@
+FROM liushuyu/osxcross@sha256:fa32af4677e2860a1c5950bc8c360f309e2a87e2ddfed27b642fddf7a6093b76
+
+ENV TARGET x86_64-apple-darwin18
+ENV TARGETNAME darwin.x86_64
+
+# Build dependencies
+USER root
+ENV DEBIAN_FRONTEND noninteractive
+RUN sed -e 's/focal/kinetic/g' -i /etc/apt/sources.list
+RUN apt-get update
+RUN apt-get dist-upgrade -y
+RUN apt-get install -y ghc automake autoconf llvm curl alex happy
+
+# Build GHC
+WORKDIR /ghc
+RUN curl -L "https://downloads.haskell.org/~ghc/9.2.5/ghc-9.2.5-src.tar.xz" | tar xJ --strip-components=1
+RUN ./configure --host x86_64-linux-gnu --build x86_64-linux-gnu --target "$TARGET"
+RUN cp mk/flavours/quick-cross.mk mk/build.mk && make -j "$(nproc)"
+RUN make install
+RUN curl -L "https://downloads.haskell.org/~cabal/cabal-install-3.9.0.0/cabal-install-3.9-x86_64-linux-alpine.tar.xz" | tar xJv -C /usr/local/bin
+
+# Due to an apparent cabal bug, we specify our options directly to cabal
+# It won't reuse caches if ghc-options are specified in ~/.cabal/config
+ENV CABALOPTS "--with-ghc=$TARGET-ghc;--with-hc-pkg=$TARGET-ghc-pkg"
+
+# Prebuild the dependencies
+RUN cabal update && IFS=';' && cabal install --dependencies-only $CABALOPTS ShellCheck
+
+# Copy the build script
+COPY build /usr/bin
+
+WORKDIR /scratch
+ENTRYPOINT ["/usr/bin/build"]

build/darwin.x86_64/build

@@ -0,0 +1,13 @@
+#!/bin/sh
+set -xe
+{
+  tar xzv --strip-components=1
+  chmod +x striptests && ./striptests
+  mkdir "$TARGETNAME"
+  ( IFS=';'; cabal build $CABALOPTS )
+  find . -name shellcheck -type f -exec mv {} "$TARGETNAME/" \;
+  ls -l "$TARGETNAME"
+  "$TARGET-strip" -Sx "$TARGETNAME/shellcheck"
+  ls -l "$TARGETNAME"
+} >&2
+tar czv "$TARGETNAME"

build/darwin.x86_64/tag

@@ -0,0 +1 @@
+koalaman/scbuilder-darwin-x86_64

build/linux.aarch64/Dockerfile

@@ -0,0 +1,40 @@
+FROM ubuntu:20.04
+
+ENV TARGET aarch64-linux-gnu
+ENV TARGETNAME linux.aarch64
+
+# Build dependencies
+USER root
+ENV DEBIAN_FRONTEND noninteractive
+
+# These deps are from 20.04, because GHC's compiler/llvm support moves slowly
+RUN apt-get update && apt-get install -y llvm gcc-$TARGET
+
+# The rest are from 22.10
+RUN sed -e 's/focal/kinetic/g' -i /etc/apt/sources.list
+# Kinetic does not receive updates anymore, switch to last available
+RUN sed -e 's/archive.ubuntu.com/old-releases.ubuntu.com/g' -i /etc/apt/sources.list
+RUN sed -e 's/security.ubuntu.com/old-releases.ubuntu.com/g' -i /etc/apt/sources.list
+
+RUN apt-get update && apt-get install -y ghc alex happy automake autoconf build-essential curl qemu-user-static
+
+# Build GHC
+WORKDIR /ghc
+RUN curl -L "https://downloads.haskell.org/~ghc/9.2.8/ghc-9.2.8-src.tar.xz" | tar xJ --strip-components=1
+RUN ./boot && ./configure --host x86_64-linux-gnu --build x86_64-linux-gnu --target "$TARGET"
+RUN cp mk/flavours/quick-cross.mk mk/build.mk && make -j "$(nproc)"
+RUN make install
+RUN curl -L "https://downloads.haskell.org/~cabal/cabal-install-3.9.0.0/cabal-install-3.9-x86_64-linux-alpine.tar.xz" | tar xJv -C /usr/local/bin
+
+# Due to an apparent cabal bug, we specify our options directly to cabal
+# It won't reuse caches if ghc-options are specified in ~/.cabal/config
+ENV CABALOPTS "--ghc-options;-split-sections -optc-Os -optc-Wl,--gc-sections -optc-fPIC;--with-ghc=$TARGET-ghc;--with-hc-pkg=$TARGET-ghc-pkg;-c;hashable -arch-native"
+
+# Prebuild the dependencies
+RUN cabal update && IFS=';' && cabal install --dependencies-only $CABALOPTS ShellCheck
+
+# Copy the build script
+COPY build /usr/bin
+
+WORKDIR /scratch
+ENTRYPOINT ["/usr/bin/build"]

build/linux.aarch64/build

@@ -0,0 +1,14 @@
+#!/bin/sh
+set -xe
+{
+  tar xzv --strip-components=1
+  chmod +x striptests && ./striptests
+  mkdir "$TARGETNAME"
+  ( IFS=';'; cabal build $CABALOPTS --enable-executable-static )
+  find . -name shellcheck -type f -exec mv {} "$TARGETNAME/" \;
+  ls -l "$TARGETNAME"
+  "$TARGET-strip" -s "$TARGETNAME/shellcheck"
+  ls -l "$TARGETNAME"
+  qemu-aarch64-static "$TARGETNAME/shellcheck" --version
+} >&2
+tar czv "$TARGETNAME"

build/linux.aarch64/tag

@@ -0,0 +1 @@
+koalaman/scbuilder-linux-aarch64

build/linux.armv6hf/Dockerfile

@@ -0,0 +1,42 @@
+# This Docker file uses a custom QEmu fork with patches to follow execve
+# to build all of ShellCheck emulated.
+
+FROM ubuntu:24.04
+
+ENV TARGETNAME linux.armv6hf
+
+# Build QEmu with execve follow support
+USER root
+ENV DEBIAN_FRONTEND noninteractive
+RUN apt-get update
+RUN apt-get install -y --no-install-recommends build-essential git ninja-build python3 pkg-config libglib2.0-dev libpixman-1-dev python3-setuptools ca-certificates debootstrap
+WORKDIR /qemu
+RUN git clone --depth 1 https://github.com/koalaman/qemu .
+RUN ./configure --static --disable-werror && cd build && ninja qemu-arm
+ENV QEMU_EXECVE 1
+
+# Convenience utility
+COPY scutil /bin/scutil
+COPY scutil /chroot/bin/scutil
+RUN chmod +x /bin/scutil /chroot/bin/scutil
+
+# Set up an armv6 userspace
+WORKDIR /
+RUN debootstrap --arch armhf --variant=minbase --foreign bookworm /chroot http://mirrordirector.raspbian.org/raspbian
+RUN cp /qemu/build/qemu-arm /chroot/bin/qemu
+RUN scutil emu /debootstrap/debootstrap --second-stage
+
+# Install deps in the chroot
+RUN scutil emu apt-get update
+RUN scutil emu apt-get install -y --no-install-recommends ghc cabal-install
+RUN scutil emu cabal update
+
+# Finally we can build the current dependencies. This takes hours.
+ENV CABALOPTS "--ghc-options;-split-sections -optc-Os -optc-Wl,--gc-sections;--gcc-options;-Os -Wl,--gc-sections -ffunction-sections -fdata-sections"
+# Generated with `cabal freeze --constraint 'hashable -arch-native'`
+COPY cabal.project.freeze /chroot/etc
+RUN IFS=";" && scutil install_from_freeze /chroot/etc/cabal.project.freeze emu cabal install $CABALOPTS
+
+# Copy the build script
+COPY build /chroot/bin
+ENTRYPOINT ["/bin/scutil", "emu", "/bin/build"]

build/linux.armv6hf/build

@@ -0,0 +1,17 @@
+#!/bin/sh
+set -xe
+mkdir /scratch && cd /scratch
+{
+  tar xzv --strip-components=1
+  cp /etc/cabal.project.freeze .
+  chmod +x striptests && ./striptests
+  mkdir "$TARGETNAME"
+  # This script does not cabal update because compiling anything new is slow
+  ( IFS=';'; cabal build $CABALOPTS --enable-executable-static )
+  find . -name shellcheck -type f -exec mv {} "$TARGETNAME/" \;
+  ls -l "$TARGETNAME"
+  strip -s "$TARGETNAME/shellcheck"
+  ls -l "$TARGETNAME"
+  "$TARGETNAME/shellcheck" --version
+} >&2
+tar czv "$TARGETNAME"

build/linux.armv6hf/cabal.project.freeze

@@ -0,0 +1,93 @@
+active-repositories: hackage.haskell.org:merge
+constraints: any.Diff ==0.5,
+             any.OneTuple ==0.4.2,
+             any.QuickCheck ==2.14.3,
+             QuickCheck -old-random +templatehaskell,
+             any.StateVar ==1.2.2,
+             any.aeson ==2.2.3.0,
+             aeson +ordered-keymap,
+             any.array ==0.5.4.0,
+             any.assoc ==1.1.1,
+             assoc -tagged,
+             any.base ==4.15.1.0,
+             any.base-orphans ==0.9.2,
+             any.bifunctors ==5.6.2,
+             bifunctors +tagged,
+             any.binary ==0.8.8.0,
+             any.bytestring ==0.10.12.1,
+             any.character-ps ==0.1,
+             any.comonad ==5.0.8,
+             comonad +containers +distributive +indexed-traversable,
+             any.containers ==0.6.4.1,
+             any.contravariant ==1.5.5,
+             contravariant +semigroups +statevar +tagged,
+             any.data-array-byte ==0.1.0.1,
+             any.data-fix ==0.3.3,
+             any.deepseq ==1.4.5.0,
+             any.directory ==1.3.6.2,
+             any.distributive ==0.6.2.1,
+             distributive +semigroups +tagged,
+             any.dlist ==1.0,
+             dlist -werror,
+             any.exceptions ==0.10.4,
+             any.fgl ==5.8.2.0,
+             fgl +containers042,
+             any.filepath ==1.4.2.1,
+             any.foldable1-classes-compat ==0.1,
+             foldable1-classes-compat +tagged,
+             any.generically ==0.1.1,
+             any.ghc-bignum ==1.1,
+             any.ghc-boot-th ==9.0.2,
+             any.ghc-prim ==0.7.0,
+             any.hashable ==1.4.6.0,
+             hashable -arch-native +integer-gmp -random-initial-seed,
+             any.indexed-traversable ==0.1.4,
+             any.indexed-traversable-instances ==0.1.2,
+             any.integer-conversion ==0.1.1,
+             any.integer-logarithms ==1.0.3.1,
+             integer-logarithms -check-bounds +integer-gmp,
+             any.mtl ==2.2.2,
+             any.network-uri ==2.6.4.2,
+             any.parsec ==3.1.14.0,
+             any.pretty ==1.1.3.6,
+             any.primitive ==0.9.0.0,
+             any.process ==1.6.13.2,
+             any.random ==1.2.1.2,
+             any.regex-base ==0.94.0.2,
+             any.regex-tdfa ==1.3.2.2,
+             regex-tdfa +doctest -force-o2,
+             any.rts ==1.0.2,
+             any.scientific ==0.3.8.0,
+             scientific -integer-simple,
+             any.semialign ==1.3.1,
+             semialign +semigroupoids,
+             any.semigroupoids ==6.0.1,
+             semigroupoids +comonad +containers +contravariant +distributive +tagged +unordered-containers,
+             any.splitmix ==0.1.0.5,
+             splitmix -optimised-mixer,
+             any.stm ==2.5.0.0,
+             any.strict ==0.5,
+             any.tagged ==0.8.8,
+             tagged +deepseq +transformers,
+             any.template-haskell ==2.17.0.0,
+             any.text ==1.2.5.0,
+             any.text-iso8601 ==0.1.1,
+             any.text-short ==0.1.6,
+             text-short -asserts,
+             any.th-abstraction ==0.7.0.0,
+             any.th-compat ==0.1.5,
+             any.these ==1.2.1,
+             any.time ==1.9.3,
+             any.time-compat ==1.9.7,
+             any.transformers ==0.5.6.2,
+             any.transformers-compat ==0.7.2,
+             transformers-compat -five +five-three -four +generic-deriving +mtl -three -two,
+             any.unix ==2.7.2.2,
+             any.unordered-containers ==0.2.20,
+             unordered-containers -debug,
+             any.uuid-types ==1.0.6,
+             any.vector ==0.13.1.0,
+             vector +boundschecks -internalchecks -unsafechecks -wall,
+             any.vector-stream ==0.1.0.1,
+             any.witherable ==0.5
+index-state: hackage.haskell.org 2024-06-18T02:21:19Z

build/linux.armv6hf/scutil

@@ -0,0 +1,48 @@
+#!/bin/dash
+# Various ShellCheck build utility functions
+
+# Generally set a ulimit to avoid QEmu using too much memory
+ulimit -v "$((10*1024*1024))"
+# If we happen to invoke or run under QEmu, make sure to follow execve.
+# This requires a patched QEmu.
+export QEMU_EXECVE=1
+
+# Retry a command until it succeeds
+# Usage: scutil retry 3 mycmd
+retry() {
+  n="$1"
+  ret=1
+  shift
+  while [ "$n" -gt 0 ]
+  do
+    "$@"
+    ret=$?
+    [ "$ret" = 0 ] && break
+    n=$((n-1))
+  done
+  return "$ret"
+}
+
+# Install all dependencies from a freeze file
+# Usage: scutil install_from_freeze /path/cabal.project.freeze cabal install
+install_from_freeze() {
+  linefeed=$(printf '\nx')
+  linefeed=${linefeed%x}
+  flags=$(
+    sed 's/constraints:/&\n /' "$1" |
+    grep -vw -e rts -e base |
+    sed -n -e 's/^  *\([^,]*\).*/\1/p' |
+    sed -e 's/any\.\([^ ]*\) ==\(.*\)/\1-\2/; te; s/.*/--constraint\n&/; :e')
+  shift
+  # shellcheck disable=SC2086
+  ( IFS=$linefeed; set -x; "$@" $flags )
+}
+
+# Run a command under emulation.
+# This assumes the correct emulator is named 'qemu' and the chroot is /chroot
+# Usage: scutil emu echo "Hello World"
+emu() {
+  chroot /chroot /bin/qemu /usr/bin/env "$@"
+}
+
+"$@"

build/linux.armv6hf/tag

@@ -0,0 +1 @@
+koalaman/scbuilder-linux-armv6hf

build/linux.riscv64/Dockerfile

@@ -0,0 +1,46 @@
+FROM ubuntu:24.04
+
+ENV TARGETNAME linux.riscv64
+ENV TARGET riscv64-linux-gnu
+
+USER root
+ENV DEBIAN_FRONTEND noninteractive
+
+# Init base
+RUN apt-get update -y
+
+# Install qemu
+RUN apt-get install -y --no-install-recommends build-essential ninja-build python3 pkg-config libglib2.0-dev libpixman-1-dev curl ca-certificates python3-virtualenv git python3-setuptools debootstrap
+WORKDIR /qemu
+RUN git clone --depth 1 https://github.com/koalaman/qemu .
+RUN ./configure --target-list=riscv64-linux-user --static --disable-system --disable-pie --disable-werror
+RUN cd build && ninja qemu-riscv64
+ENV QEMU_EXECVE 1
+
+# Convenience utility
+COPY scutil /bin/scutil
+# We have to copy to /usr/bin because debootstrap will try to symlink /bin and fail if it exists
+COPY scutil /chroot/usr/bin/scutil
+RUN chmod +x /bin/scutil /chroot/usr/bin/scutil
+
+# Set up a riscv64 userspace
+WORKDIR /
+RUN debootstrap --arch=riscv64 --variant=minbase --components=main,universe --foreign noble /chroot http://ports.ubuntu.com/ubuntu-ports
+RUN cp /qemu/build/qemu-riscv64 /chroot/bin/qemu
+RUN scutil emu /debootstrap/debootstrap --second-stage
+
+# Install deps in the chroot
+RUN scutil emu apt-get update
+RUN scutil emu apt-get install -y --no-install-recommends ghc cabal-install
+RUN scutil emu cabal update
+
+# Generated with: cabal freeze -c 'hashable -arch-native'. We put it in /etc so cabal won't find it.
+COPY cabal.project.freeze /chroot/etc
+
+# Build all dependencies from the freeze file. The emulator segfaults at random,
+# so retry a few times.
+RUN scutil install_from_freeze /chroot/etc/cabal.project.freeze retry 5 emu cabal install --keep-going
+
+# Copy the build script
+COPY build /chroot/bin/build
+ENTRYPOINT ["/bin/scutil", "emu", "/bin/build"]

build/linux.riscv64/build

@@ -0,0 +1,21 @@
+#!/bin/sh
+set -xe
+IFS=';'
+{
+  mkdir -p /tmp/scratch
+  cd /tmp/scratch
+  tar xzv --strip-components=1
+  chmod +x striptests && ./striptests
+  # Use a freeze file to ensure we use the same dependencies we cached during
+  # the docker image build. We don't want to spend time compiling anything new.
+  cp /etc/cabal.project.freeze .
+  mkdir "$TARGETNAME"
+  # Retry in case of random segfault
+  scutil retry 3 cabal build --enable-executable-static
+  find . -name shellcheck -type f -exec mv {} "$TARGETNAME/" \;
+  ls -l "$TARGETNAME"
+  "$TARGET-strip" -s "$TARGETNAME/shellcheck"
+  ls -l "$TARGETNAME"
+  "$TARGETNAME/shellcheck" --version
+} >&2
+tar czv "$TARGETNAME"

build/linux.riscv64/cabal.project.freeze

@@ -0,0 +1,93 @@
+active-repositories: hackage.haskell.org:merge
+constraints: any.Diff ==0.5,
+             any.OneTuple ==0.4.2,
+             any.QuickCheck ==2.14.3,
+             QuickCheck -old-random +templatehaskell,
+             any.StateVar ==1.2.2,
+             any.aeson ==2.2.3.0,
+             aeson +ordered-keymap,
+             any.array ==0.5.4.0,
+             any.assoc ==1.1.1,
+             assoc -tagged,
+             any.base ==4.17.2.0,
+             any.base-orphans ==0.9.2,
+             any.bifunctors ==5.6.2,
+             bifunctors +tagged,
+             any.binary ==0.8.9.1,
+             any.bytestring ==0.11.5.2,
+             any.character-ps ==0.1,
+             any.comonad ==5.0.8,
+             comonad +containers +distributive +indexed-traversable,
+             any.containers ==0.6.7,
+             any.contravariant ==1.5.5,
+             contravariant +semigroups +statevar +tagged,
+             any.data-fix ==0.3.3,
+             any.deepseq ==1.4.8.0,
+             any.directory ==1.3.7.1,
+             any.distributive ==0.6.2.1,
+             distributive +semigroups +tagged,
+             any.dlist ==1.0,
+             dlist -werror,
+             any.exceptions ==0.10.5,
+             any.fgl ==5.8.2.0,
+             fgl +containers042,
+             any.filepath ==1.4.2.2,
+             any.foldable1-classes-compat ==0.1,
+             foldable1-classes-compat +tagged,
+             any.generically ==0.1.1,
+             any.ghc-bignum ==1.3,
+             any.ghc-boot-th ==9.4.7,
+             any.ghc-prim ==0.9.1,
+             any.hashable ==1.4.6.0,
+             hashable -arch-native +integer-gmp -random-initial-seed,
+             any.indexed-traversable ==0.1.4,
+             any.indexed-traversable-instances ==0.1.2,
+             any.integer-conversion ==0.1.1,
+             any.integer-logarithms ==1.0.3.1,
+             integer-logarithms -check-bounds +integer-gmp,
+             any.mtl ==2.2.2,
+             any.network-uri ==2.6.4.2,
+             any.os-string ==2.0.3,
+             any.parsec ==3.1.16.1,
+             any.pretty ==1.1.3.6,
+             any.primitive ==0.9.0.0,
+             any.process ==1.6.17.0,
+             any.random ==1.2.1.2,
+             any.regex-base ==0.94.0.2,
+             any.regex-tdfa ==1.3.2.2,
+             regex-tdfa +doctest -force-o2,
+             any.rts ==1.0.2,
+             any.scientific ==0.3.8.0,
+             scientific -integer-simple,
+             any.semialign ==1.3.1,
+             semialign +semigroupoids,
+             any.semigroupoids ==6.0.1,
+             semigroupoids +comonad +containers +contravariant +distributive +tagged +unordered-containers,
+             any.splitmix ==0.1.0.5,
+             splitmix -optimised-mixer,
+             any.stm ==2.5.1.0,
+             any.strict ==0.5,
+             any.tagged ==0.8.8,
+             tagged +deepseq +transformers,
+             any.template-haskell ==2.19.0.0,
+             any.text ==2.0.2,
+             any.text-iso8601 ==0.1.1,
+             any.text-short ==0.1.6,
+             text-short -asserts,
+             any.th-abstraction ==0.7.0.0,
+             any.th-compat ==0.1.5,
+             any.these ==1.2.1,
+             any.time ==1.12.2,
+             any.time-compat ==1.9.7,
+             any.transformers ==0.5.6.2,
+             any.transformers-compat ==0.7.2,
+             transformers-compat -five +five-three -four +generic-deriving +mtl -three -two,
+             any.unix ==2.7.3,
+             any.unordered-containers ==0.2.20,
+             unordered-containers -debug,
+             any.uuid-types ==1.0.6,
+             any.vector ==0.13.1.0,
+             vector +boundschecks -internalchecks -unsafechecks -wall,
+             any.vector-stream ==0.1.0.1,
+             any.witherable ==0.5
+index-state: hackage.haskell.org 2024-06-17T00:48:51Z

build/linux.riscv64/tag

@@ -0,0 +1 @@
+koalaman/scbuilder-linux-riscv64

build/linux.x86_64/Dockerfile

@@ -0,0 +1,24 @@
+FROM alpine:3.16
+# alpine:3.16 (GHC 9.0.1):  5.8 megabytes
+# alpine:3.17 (GHC 9.0.2): 15.0 megabytes
+# alpine:3.18 (GHC 9.4.4): 29.0 megabytes
+# alpine:3.19 (GHC 9.4.7): 29.0 megabytes
+
+ENV TARGETNAME linux.x86_64
+
+# Install GHC and cabal
+USER root
+RUN apk add ghc cabal g++ libffi-dev curl bash
+
+# Use ld.bfd instead of ld.gold due to
+# x86_64-linux-gnu/libpthread.a(pthread_cond_init.o)(.note.stapsdt+0x14): error:
+#    relocation refers to local symbol "" [2], which is defined in a discarded section
+ENV CABALOPTS "--ghc-options;-optl-Wl,-fuse-ld=bfd -split-sections -optc-Os -optc-Wl,--gc-sections"
+
+# Other archs pre-build dependencies here, but this one doesn't to detect ecosystem movement
+
+# Copy the build script
+COPY build /usr/bin
+
+WORKDIR /scratch
+ENTRYPOINT ["/usr/bin/build"]

build/linux.x86_64/build

@@ -0,0 +1,15 @@
+#!/bin/sh
+set -xe
+{
+  tar xzv --strip-components=1
+  chmod +x striptests && ./striptests
+  mkdir "$TARGETNAME"
+  cabal update
+  ( IFS=';'; cabal build $CABALOPTS --enable-executable-static )
+  find . -name shellcheck -type f -exec mv {} "$TARGETNAME/" \;
+  ls -l "$TARGETNAME"
+  strip -s "$TARGETNAME/shellcheck"
+  ls -l "$TARGETNAME"
+  "$TARGETNAME/shellcheck" --version
+} >&2
+tar czv "$TARGETNAME"

build/linux.x86_64/tag

@@ -0,0 +1 @@
+koalaman/scbuilder-linux-x86_64

build/run_builder

@@ -0,0 +1,30 @@
+#!/bin/bash
+if [ $# -lt 2 ]
+then
+  echo >&2 "This script builds a source archive (as produced by cabal sdist)"
+  echo >&2 "Usage: $0 sourcefile.tar.gz builddir..."
+  exit 1
+fi
+
+file=$(realpath "$1")
+shift
+
+if [ ! -e "$file" ]
+then
+  echo >&2 "$file does not exist"
+  exit 1
+fi
+
+set -ex -o pipefail
+
+for dir
+do
+  tagfile="$dir/tag"
+  if [ ! -e "$tagfile" ]
+  then
+    echo >&2 "$tagfile does not exist"
+    exit 2
+  fi
+
+  docker run -i "$(< "$tagfile")" < "$file" | tar xz
+done

build/windows.x86_64/Dockerfile

@@ -0,0 +1,27 @@
+FROM ubuntu:20.04
+
+ENV TARGETNAME windows.x86_64
+
+# We don't need wine32, even though it complains
+USER root
+ENV DEBIAN_FRONTEND noninteractive
+RUN apt-get update && apt-get install -y curl busybox wine winbind
+
+# Fetch Windows version, will be available under z:\haskell
+WORKDIR /haskell
+RUN curl -L "https://downloads.haskell.org/~ghc/8.10.4/ghc-8.10.4-x86_64-unknown-mingw32.tar.xz" | tar xJ --strip-components=1
+WORKDIR /haskell/bin
+RUN curl -L "https://downloads.haskell.org/~cabal/cabal-install-3.2.0.0/cabal-install-3.2.0.0-x86_64-unknown-mingw32.zip" | busybox unzip -
+RUN curl -L "https://curl.se/windows/dl-8.7.1_7/curl-8.7.1_7-win64-mingw.zip" | busybox unzip - && mv curl-*-win64-mingw/bin/* .
+ENV WINEPATH /haskell/bin
+
+# It's unknown whether Cabal on Windows suffers from the same issue
+# that necessitated this but I don't care enough to find out
+ENV CABALOPTS "--ghc-options;-split-sections -optc-Os -optc-Wl,--gc-sections"
+
+# Precompile some deps to speed up later builds
+RUN wine /haskell/bin/cabal.exe update && IFS=';' && wine /haskell/bin/cabal.exe install --lib --dependencies-only $CABALOPTS ShellCheck
+
+COPY build /usr/bin
+WORKDIR /scratch
+ENTRYPOINT ["/usr/bin/build"]

build/windows.x86_64/build

@@ -0,0 +1,18 @@
+#!/bin/sh
+cabal() {
+  wine /haskell/bin/cabal.exe  "$@"
+}
+
+set -xe
+{
+  tar xzv --strip-components=1
+  chmod +x striptests && ./striptests
+  mkdir "$TARGETNAME"
+  ( IFS=';'; cabal build $CABALOPTS )
+  find dist*/ -name shellcheck.exe -type f -ls -exec mv {} "$TARGETNAME/" \;
+  ls -l "$TARGETNAME"
+  wine "/haskell/mingw/bin/strip.exe" -s "$TARGETNAME/shellcheck.exe"
+  ls -l "$TARGETNAME"
+  wine "$TARGETNAME/shellcheck.exe" --version
+} >&2
+tar czv "$TARGETNAME"

build/windows.x86_64/tag

@@ -0,0 +1 @@
+koalaman/scbuilder-windows-x86_64

manpage

@@ -0,0 +1,4 @@
+#!/bin/sh
+echo >&2 "Generating man page using pandoc"
+pandoc -s -f markdown-smart -t man shellcheck.1.md -o shellcheck.1 || exit
+echo >&2 "Done. You can read it with:   man ./shellcheck.1"

nextnumber

@@ -6,8 +6,8 @@ then
   exit 1
 fi
 
-for i in 1 2
+for i in 1 2 3
 do
-  last=$(grep -hv "^prop" ./**/*.hs | grep -Ewo "$i[0-9]{3}" | sort -n | tail -n 1)
+  last=$(grep -hv "^prop" ./**/*.hs | grep -Ewo "${i}[0-9]{3}" | sort -n | tail -n 1)
   echo "Next ${i}xxx: $((last+1))"
 done

quickrun

@@ -2,4 +2,12 @@
 # quickrun runs ShellCheck in an interpreted mode.
 # This allows testing changes without recompiling.
 
-runghc -isrc -idist/build/autogen shellcheck.hs "$@"
+path=$(find . -type f -path './dist*/Paths_ShellCheck.hs' | sort | head -n 1)
+if [ -z "$path" ]
+then
+  echo >&2 "Unable to find Paths_ShellCheck.hs. Please 'cabal build' once."
+  exit 1
+fi
+path="${path%/*}"
+
+exec runghc -isrc -i"$path" shellcheck.hs "$@"

quicktest

@@ -3,8 +3,17 @@
 # This allows running tests without compiling, which can be faster.
 # 'cabal test' remains the source of truth.
 
+path=$(find . -type f -path './dist*/Paths_ShellCheck.hs' | sort | head -n 1)
+if [ -z "$path" ]
+then
+    echo >&2 "Unable to find Paths_ShellCheck.hs. Please 'cabal build' once."
+      exit 1
+fi
+path="${path%/*}"
+
+
 (
-var=$(echo 'main' | ghci test/shellcheck.hs 2>&1 | tee /dev/stderr)
+var=$(echo 'main' | ghci -isrc -i"$path" test/shellcheck.hs 2>&1 | tee /dev/stderr)
 if [[ $var == *ExitSuccess* ]]
 then
   exit 0

setgitversion

@@ -0,0 +1,11 @@
+#!/bin/sh -xe
+# This script hardcodes the `git describe` version as ShellCheck's version number.
+# This is done to allow shellcheck --version to differ from the cabal version when
+# building git snapshots.
+
+file="src/ShellCheck/Data.hs"
+test -e "$file"
+tmp=$(mktemp)
+version=$(git describe)
+sed -e "s/=.*VERSIONSTRING.*/= \"$version\" -- VERSIONSTRING, DO NOT SUBMIT/" "$file" > "$tmp"
+mv "$tmp" "$file"

shellcheck.1.md

@@ -56,6 +56,13 @@ not warn at all, as `ksh` supports decimals in arithmetic contexts.
     options are cumulative, but all the codes can be specified at once,
     comma-separated as a single argument.
 
+**--extended-analysis=true/false**
+
+:   Enable/disable Dataflow Analysis to identify more issues (default true). If
+    ShellCheck uses too much CPU/RAM when checking scripts with several
+    thousand lines of code, extended analysis can be disabled with this flag
+    or a directive. This flag overrides directives and rc files.
+
 **-f** *FORMAT*, **--format=***FORMAT*
 
 :   Specify the output format of shellcheck, which prints its results in the
@@ -71,6 +78,11 @@ not warn at all, as `ksh` supports decimals in arithmetic contexts.
 
 :   Don't try to look for .shellcheckrc configuration files.
 
+**--rcfile** *RCFILE*
+
+:   Prefer the specified configuration file over searching for one
+    in the default locations.
+
 **-o**\ *NAME1*[,*NAME2*...],\ **--enable=***NAME1*[,*NAME2*...]
 
 :   Enable optional checks. The special name *all* enables all of them.
@@ -85,7 +97,8 @@ not warn at all, as `ksh` supports decimals in arithmetic contexts.
 
 **-s**\ *shell*,\ **--shell=***shell*
 
-:   Specify Bourne shell dialect. Valid values are *sh*, *bash*, *dash* and *ksh*.
+:   Specify Bourne shell dialect. Valid values are *sh*, *bash*, *dash*, *ksh*,
+    and *busybox*.
     The default is to deduce the shell from the file's `shell` directive,
     shebang, or `.bash/.bats/.dash/.ksh` extension, in that order. *sh* refers to
     POSIX `sh` (not the system's), and will warn of portability issues.
@@ -107,11 +120,14 @@ not warn at all, as `ksh` supports decimals in arithmetic contexts.
 
 **-x**,\ **--external-sources**
 
-:   Follow 'source' statements even when the file is not specified as input.
+:   Follow `source` statements even when the file is not specified as input.
     By default, `shellcheck` will only follow files specified on the command
     line (plus `/dev/null`). This option allows following any file the script
     may `source`.
 
+    This option may also be enabled using `external-sources=true` in
+    `.shellcheckrc`. This flag takes precedence.
+
 **FILES...**
 
 :   One or more script files to check, or "-" for standard input.
@@ -232,12 +248,28 @@ Valid keys are:
 **disable**
 :   Disables a comma separated list of error codes for the following command.
     The command can be a simple command like `echo foo`, or a compound command
-    like a function definition, subshell block or loop.
+    like a function definition, subshell block or loop. A range can be
+    be specified with a dash, e.g. `disable=SC3000-SC4000` to exclude 3xxx.
+    All warnings can be disabled with `disable=all`.
 
 **enable**
 :   Enable an optional check by name, as listed with **--list-optional**.
     Only file-wide `enable` directives are considered.
 
+**extended-analysis**
+:   Set to true/false to enable/disable dataflow analysis. Specifying
+    `# shellcheck extended-analysis=false` in particularly large (2000+ line)
+    auto-generated scripts will reduce ShellCheck's resource usage at the
+    expense of certain checks. Extended analysis is enabled by default.
+
+**external-sources**
+:   Set to `true` in `.shellcheckrc` to always allow ShellCheck to open
+    arbitrary files from 'source' statements (the way most tools do).
+
+    This option defaults to `false` only due to ShellCheck's origin as a
+    remote service for checking untrusted scripts. It can safely be enabled
+    for normal development.
+
 **source**
 :   Overrides the filename included by a `source`/`.` statement. This can be
     used to tell shellcheck where to look for a file whose name is determined
@@ -254,7 +286,7 @@ Valid keys are:
 **shell**
 :   Overrides the shell detected from the shebang.  This is useful for
     files meant to be included (and thus lacking a shebang), or possibly
-    as a more targeted alternative to 'disable=2039'.
+    as a more targeted alternative to 'disable=SC2039'.
 
 # RC FILES
 
@@ -269,17 +301,23 @@ Here is an example `.shellcheckrc`:
     source-path=SCRIPTDIR
     source-path=/mnt/chroot
 
+    # Since 0.9.0, values can be quoted with '' or "" to allow spaces
+    source-path="My Documents/scripts"
+
+    # Allow opening any 'source'd file, even if not specified as input
+    external-sources=true
+
     # Turn on warnings for unquoted variables with safe values
     enable=quote-safe-variables
 
     # Turn on warnings for unassigned uppercase variables
     enable=check-unassigned-uppercase
 
-    # Allow using `which` since it gives full paths and is common enough
-    disable=SC2230
+    # Allow [ ! -z foo ] instead of suggesting -n
+    disable=SC2236
 
 If no `.shellcheckrc` is found in any of the parent directories, ShellCheck
-will look in `~/.shellcheckrc` followed by the XDG config directory
+will look in `~/.shellcheckrc` followed by the `$XDG_CONFIG_HOME`
 (usually `~/.config/shellcheckrc`) on Unix, or `%APPDATA%/shellcheckrc` on
 Windows. Only the first file found will be used.
 
@@ -301,7 +339,7 @@ invocation.
 
 # RETURN VALUES
 
-ShellCheck uses the follow exit codes:
+ShellCheck uses the following exit codes:
 
 + 0: All files successfully scanned with no issues.
 + 1: All files successfully scanned with some issues.
@@ -319,10 +357,32 @@ locales where encoding is unspecified (such as the `C` locale).
 Windows users seeing `commitBuffer: invalid argument (invalid character)`
 should set their terminal to use UTF-8 with `chcp 65001`.
 
-# AUTHORS
+# KNOWN INCOMPATIBILITIES
 
-ShellCheck is developed and maintained by Vidar Holen, with assistance from a
-long list of wonderful contributors.
+(If nothing in this section makes sense, you are unlikely to be affected by it)
+
+To avoid confusing and misguided suggestions, ShellCheck requires function
+bodies to be either `{ brace groups; }` or `( subshells )`, and function names
+containing `[]*=!` are only recognized after a `function` keyword.
+
+The following unconventional function definitions are identical in Bash,
+but ShellCheck only recognizes the latter.
+
+    [x!=y] () [[ $1 ]]
+    function [x!=y] () { [[ $1 ]]; }
+
+Shells without the `function` keyword do not allow these characters in function
+names to begin with.  Function names containing `{}` are not supported at all.
+
+Further, if ShellCheck sees `[x!=y]` it will assume this is an invalid
+comparison. To invoke the above function, quote the command as in `'[x!=y]'`,
+or to retain the same globbing behavior, use `command [x!=y]`.
+
+ShellCheck imposes additional restrictions on the `[` command to help diagnose
+common invalid uses. While `[ $x= 1 ]` is defined in POSIX, ShellCheck will
+assume it was intended as the much more likely comparison `[ "$x" = 1 ]` and
+fail accordingly. For unconventional or dynamic uses of the `[` command, use
+`test` or `\[` instead.
 
 # REPORTING BUGS
 
@@ -330,12 +390,17 @@ Bugs and issues can be reported on GitHub:
 
 https://github.com/koalaman/shellcheck/issues
 
+# AUTHORS
+
+ShellCheck is developed and maintained by Vidar Holen, with assistance from a
+long list of wonderful contributors.
+
 # COPYRIGHT
 
-Copyright 2012-2019, Vidar Holen and contributors.
+Copyright 2012-2024, Vidar Holen and contributors.
 Licensed under the GNU General Public License version 3 or later,
 see https://gnu.org/licenses/gpl.html
 
 # SEE ALSO
 
-sh(1) bash(1)
+sh(1) bash(1) dash(1) ksh(1)

shellcheck.hs

@@ -34,6 +34,8 @@ import qualified ShellCheck.Formatter.Quiet
 
 import           Control.Exception
 import           Control.Monad
+import           Control.Monad.IO.Class
+import           Control.Monad.Trans.Class
 import           Control.Monad.Except
 import           Data.Bits
 import           Data.Char
@@ -74,7 +76,8 @@ data Options = Options {
     externalSources  :: Bool,
     sourcePaths      :: [FilePath],
     formatterOptions :: FormatterOptions,
-    minSeverity      :: Severity
+    minSeverity      :: Severity,
+    rcfile           :: Maybe FilePath
 }
 
 defaultOptions = Options {
@@ -84,7 +87,8 @@ defaultOptions = Options {
     formatterOptions = newFormatterOptions {
         foColorOption = ColorAuto
     },
-    minSeverity = StyleC
+    minSeverity = StyleC,
+    rcfile = Nothing
 }
 
 usageHeader = "Usage: shellcheck [OPTIONS...] FILES..."
@@ -98,6 +102,8 @@ options = [
         (ReqArg (Flag "include") "CODE1,CODE2..") "Consider only given types of warnings",
     Option "e" ["exclude"]
         (ReqArg (Flag "exclude") "CODE1,CODE2..") "Exclude types of warnings",
+    Option "" ["extended-analysis"]
+        (ReqArg (Flag "extended-analysis") "bool") "Perform dataflow analysis (default true)",
     Option "f" ["format"]
         (ReqArg (Flag "format") "FORMAT") $
         "Output format (" ++ formatList ++ ")",
@@ -105,6 +111,9 @@ options = [
         (NoArg $ Flag "list-optional" "true") "List checks disabled by default",
     Option "" ["norc"]
         (NoArg $ Flag "norc" "true") "Don't look for .shellcheckrc files",
+    Option "" ["rcfile"]
+        (ReqArg (Flag "rcfile") "RCFILE")
+        "Prefer the specified configuration file over searching for one",
     Option "o" ["enable"]
         (ReqArg (Flag "enable") "check1,check2..")
         "List of optional checks to enable (or 'all')",
@@ -113,7 +122,7 @@ options = [
         "Specify path when looking for sourced files (\"SCRIPTDIR\" for script's dir)",
     Option "s" ["shell"]
         (ReqArg (Flag "shell") "SHELLNAME")
-        "Specify dialect (sh, bash, dash, ksh)",
+        "Specify dialect (sh, bash, dash, ksh, busybox)",
     Option "S" ["severity"]
         (ReqArg (Flag "severity") "SEVERITY")
         "Minimum severity of errors to consider (error, warning, info, style)",
@@ -225,7 +234,7 @@ runFormatter sys format options files = do
     f :: Status -> FilePath -> IO Status
     f status file = do
         newStatus <- process file `catch` handler file
-        return $ status `mappend` newStatus
+        return $! status `mappend` newStatus
     handler :: FilePath -> IOException -> IO Status
     handler file e = reportFailure file (show e)
     reportFailure file str = do
@@ -234,7 +243,7 @@ runFormatter sys format options files = do
 
     process :: FilePath -> IO Status
     process filename = do
-        input <- siReadFile sys filename
+        input <- siReadFile sys Nothing filename
         either (reportFailure filename) check input
       where
         check contents = do
@@ -250,9 +259,9 @@ runFormatter sys format options files = do
                 else SomeProblems
 
 parseEnum name value list =
-    case filter ((== value) . fst) list of
-        [(name, value)] -> return value
-        [] -> do
+    case lookup value list of
+        Just value -> return value
+        Nothing -> do
             printErr $ "Unknown value for --" ++ name ++ ". " ++
                        "Valid options are: " ++ (intercalate ", " $ map fst list)
             throwError SupportFailure
@@ -365,6 +374,11 @@ parseOption flag options =
                 }
             }
 
+        Flag "rcfile" str -> do
+            return options {
+                rcfile = Just str
+            }
+
         Flag "enable" value ->
             let cs = checkSpec options in return options {
                 checkSpec = cs {
@@ -372,6 +386,14 @@ parseOption flag options =
                 }
             }
 
+        Flag "extended-analysis" str -> do
+            value <- parseBool str
+            return options {
+                checkSpec = (checkSpec options) {
+                    csExtendedAnalysis = Just value
+                }
+            }
+
         -- This flag is handled specially in 'process'
         Flag "format" _ -> return options
 
@@ -389,11 +411,20 @@ parseOption flag options =
             throwError SyntaxFailure
         return (Prelude.read num :: Integer)
 
+    parseBool str = do
+        case str of
+            "true" -> return True
+            "false" -> return False
+            _ -> do
+                printErr $ "Invalid boolean, expected true/false: " ++ str
+                throwError SyntaxFailure
+
+ioInterface :: Options -> [FilePath] -> IO (SystemInterface IO)
 ioInterface options files = do
     inputs <- mapM normalize files
     cache <- newIORef emptyCache
     configCache <- newIORef ("", Nothing)
-    return SystemInterface {
+    return (newSystemInterface :: SystemInterface IO) {
         siReadFile = get cache inputs,
         siFindSource = findSourceFile inputs (sourcePaths options),
         siGetConfig = getConfig configCache
@@ -402,14 +433,14 @@ ioInterface options files = do
     emptyCache :: Map.Map FilePath String
     emptyCache = Map.empty
 
-    get cache inputs file = do
+    get cache inputs rcSuggestsExternal file = do
         map <- readIORef cache
         case Map.lookup file map of
             Just x  -> return $ Right x
-            Nothing -> fetch cache inputs file
+            Nothing -> fetch cache inputs rcSuggestsExternal file
 
-    fetch cache inputs file = do
-        ok <- allowable inputs file
+    fetch cache inputs rcSuggestsExternal file = do
+        ok <- allowable rcSuggestsExternal inputs file
         if ok
           then (do
             (contents, shouldCache) <- inputFile file
@@ -417,13 +448,16 @@ ioInterface options files = do
                 modifyIORef cache $ Map.insert file contents
             return $ Right contents
             ) `catch` handler
+          else
+            if rcSuggestsExternal == Just False
+            then return $ Left (file ++ " was not specified as input, and external files were disabled via directive.")
             else return $ Left (file ++ " was not specified as input (see shellcheck -x).")
       where
         handler :: IOException -> IO (Either ErrorMessage String)
         handler ex = return . Left $ show ex
 
-    allowable inputs x =
-        if externalSources options
+    allowable rcSuggestsExternal inputs x =
+        if fromMaybe (externalSources options) rcSuggestsExternal
         then return True
         else do
             path <- normalize x
@@ -435,8 +469,23 @@ ioInterface options files = do
         fallback :: FilePath -> IOException -> IO FilePath
         fallback path _ = return path
 
+
     -- Returns the name and contents of .shellcheckrc for the given file
-    getConfig cache filename = do
+    getConfig cache filename =
+        case rcfile options of
+            Just file -> do
+                -- We have a specified rcfile. Ignore normal rcfile resolution.
+                (path, result) <- readIORef cache
+                if path == "/"
+                  then return result
+                  else do
+                    result <- readConfig file
+                    when (isNothing result) $
+                        hPutStrLn stderr $ "Warning: unable to read --rcfile " ++ file
+                    writeIORef cache ("/", result)
+                    return result
+
+            Nothing -> do
                 path <- normalize filename
                 let dir = takeDirectory path
                 (previousPath, result) <- readIORef cache
@@ -484,14 +533,20 @@ ioInterface options files = do
       where
         handler :: FilePath -> IOException -> IO (String, Bool)
         handler file err = do
-            putStrLn $ file ++ ": " ++ show err
+            hPutStrLn stderr $ file ++ ": " ++ show err
             return ("", True)
 
     andM a b arg = do
         first <- a arg
         if not first then return False else b arg
 
-    findSourceFile inputs sourcePathFlag currentScript sourcePathAnnotation original =
+    findM p = foldr go (pure Nothing)
+      where
+        go x acc = do
+            b <- p x
+            if b then pure (Just x) else acc
+
+    findSourceFile inputs sourcePathFlag currentScript rcSuggestsExternal sourcePathAnnotation original =
         if isAbsolute original
         then
             let (_, relative) = splitDrive original
@@ -500,11 +555,11 @@ ioInterface options files = do
             find original original
       where
         find filename deflt = do
-            sources <- filterM ((allowable inputs) `andM` doesFileExist) $
-                        (adjustPath filename):(map (</> filename) $ map adjustPath $ sourcePathFlag ++ sourcePathAnnotation)
+            sources <- findM ((allowable rcSuggestsExternal inputs) `andM` doesFileExist) $
+                        (adjustPath filename):(map ((</> filename) . adjustPath) $ sourcePathFlag ++ sourcePathAnnotation)
             case sources of
-                [] -> return deflt
-                (first:_) -> return first
+                Nothing -> return deflt
+                Just first -> return first
         scriptdir = dropFileName currentScript
         adjustPath str =
             case (splitDirectories str) of

snap/snapcraft.yaml

@@ -23,7 +23,7 @@ description: |
       # snap connect shellcheck:removable-media
 
 version: git
-base: core18
+base: core20
 grade: stable
 confinement: strict
 
@@ -31,6 +31,8 @@ apps:
   shellcheck:
     command: usr/bin/shellcheck
     plugs: [home, removable-media]
+    environment:
+      LANG: C.UTF-8
 
 parts:
   shellcheck:
@@ -38,16 +40,16 @@ parts:
     source: .
     build-packages:
       - cabal-install
-      - squid
+    stage-packages:
+      - libatomic1
     override-build: |
-      # See comments in .snapsquid.conf
-      [ "$http_proxy" ] && {
-        squid3 -f .snapsquid.conf
-        export http_proxy="http://localhost:8888"
-        sleep 3
-      }
+      # Give ourselves enough memory to build
+      dd if=/dev/zero of=/tmp/swap bs=1M count=2000
+      mkswap /tmp/swap
+      swapon /tmp/swap
+
       cabal sandbox init
-      cabal update || cat /var/log/squid/*
+      cabal update
       cabal install -j
 
       install -d $SNAPCRAFT_PART_INSTALL/usr/bin

src/ShellCheck/AST.hs

@@ -17,7 +17,7 @@
     You should have received a copy of the GNU General Public License
     along with this program.  If not, see <https://www.gnu.org/licenses/>.
 -}
-{-# LANGUAGE DeriveGeneric, DeriveAnyClass #-}
+{-# LANGUAGE DeriveGeneric, DeriveAnyClass, DeriveTraversable, PatternSynonyms #-}
 module ShellCheck.AST where
 
 import GHC.Generics (Generic)
@@ -37,354 +37,245 @@ newtype FunctionParentheses = FunctionParentheses Bool deriving (Show, Eq)
 data CaseType = CaseBreak | CaseFallThrough | CaseContinue deriving (Show, Eq)
 
 newtype Root = Root Token
-data Token =
-    TA_Binary Id String Token Token
-    | TA_Assignment Id String Token Token
-    | TA_Variable Id String [Token]
-    | TA_Expansion Id [Token]
-    | TA_Sequence Id [Token]
-    | TA_Trinary Id Token Token Token
-    | TA_Unary Id String Token
-    | TC_And Id ConditionType String Token Token
-    | TC_Binary Id ConditionType String Token Token
-    | TC_Group Id ConditionType Token
-    | TC_Nullary Id ConditionType Token
-    | TC_Or Id ConditionType String Token Token
-    | TC_Unary Id ConditionType String Token
-    | TC_Empty Id ConditionType
-    | T_AND_IF Id
-    | T_AndIf Id Token Token
-    | T_Arithmetic Id Token
-    | T_Array Id [Token]
-    | T_IndexedElement Id [Token] Token
+data Token = OuterToken Id (InnerToken Token) deriving (Show)
+
+data InnerToken t =
+    Inner_TA_Binary String t t
+    | Inner_TA_Assignment String t t
+    | Inner_TA_Variable String [t]
+    | Inner_TA_Expansion [t]
+    | Inner_TA_Sequence [t]
+    | Inner_TA_Parenthesis t
+    | Inner_TA_Trinary t t t
+    | Inner_TA_Unary String t
+    | Inner_TC_And ConditionType String t t
+    | Inner_TC_Binary ConditionType String t t
+    | Inner_TC_Group ConditionType t
+    | Inner_TC_Nullary ConditionType t
+    | Inner_TC_Or ConditionType String t t
+    | Inner_TC_Unary ConditionType String t
+    | Inner_TC_Empty ConditionType
+    | Inner_T_AND_IF
+    | Inner_T_AndIf t t
+    | Inner_T_Arithmetic t
+    | Inner_T_Array [t]
+    | Inner_T_IndexedElement [t] t
     -- Store the index as string, and parse as arithmetic or string later
-    | T_UnparsedIndex Id SourcePos String
-    | T_Assignment Id AssignmentMode String [Token] Token
-    | T_Backgrounded Id Token
-    | T_Backticked Id [Token]
-    | T_Bang Id
-    | T_Banged Id Token
-    | T_BraceExpansion Id [Token]
-    | T_BraceGroup Id [Token]
-    | T_CLOBBER Id
-    | T_Case Id
-    | T_CaseExpression Id Token [(CaseType, [Token], [Token])]
-    | T_Condition Id ConditionType Token
-    | T_DGREAT Id
-    | T_DLESS Id
-    | T_DLESSDASH Id
-    | T_DSEMI Id
-    | T_Do Id
-    | T_DollarArithmetic Id Token
-    | T_DollarBraced Id Bool Token
-    | T_DollarBracket Id Token
-    | T_DollarDoubleQuoted Id [Token]
-    | T_DollarExpansion Id [Token]
-    | T_DollarSingleQuoted Id String
-    | T_DollarBraceCommandExpansion Id [Token]
-    | T_Done Id
-    | T_DoubleQuoted Id [Token]
-    | T_EOF Id
-    | T_Elif Id
-    | T_Else Id
-    | T_Esac Id
-    | T_Extglob Id String [Token]
-    | T_FdRedirect Id String Token
-    | T_Fi Id
-    | T_For Id
-    | T_ForArithmetic Id Token Token Token [Token]
-    | T_ForIn Id String [Token] [Token]
-    | T_Function Id FunctionKeyword FunctionParentheses String Token
-    | T_GREATAND Id
-    | T_Glob Id String
-    | T_Greater Id
-    | T_HereDoc Id Dashed Quoted String [Token]
-    | T_HereString Id Token
-    | T_If Id
-    | T_IfExpression Id [([Token],[Token])] [Token]
-    | T_In  Id
-    | T_IoFile Id Token Token
-    | T_IoDuplicate Id Token String
-    | T_LESSAND Id
-    | T_LESSGREAT Id
-    | T_Lbrace Id
-    | T_Less Id
-    | T_Literal Id String
-    | T_Lparen Id
-    | T_NEWLINE Id
-    | T_NormalWord Id [Token]
-    | T_OR_IF Id
-    | T_OrIf Id Token Token
-    | T_ParamSubSpecialChar Id String -- e.g. '%' in ${foo%bar}  or '/' in ${foo/bar/baz}
-    | T_Pipeline Id [Token] [Token] -- [Pipe separators] [Commands]
-    | T_ProcSub Id String [Token]
-    | T_Rbrace Id
-    | T_Redirecting Id [Token] Token
-    | T_Rparen Id
-    | T_Script Id Token [Token] -- Shebang T_Literal, followed by script.
-    | T_Select Id
-    | T_SelectIn Id String [Token] [Token]
-    | T_Semi Id
-    | T_SimpleCommand Id [Token] [Token]
-    | T_SingleQuoted Id String
-    | T_Subshell Id [Token]
-    | T_Then Id
-    | T_Until Id
-    | T_UntilExpression Id [Token] [Token]
-    | T_While Id
-    | T_WhileExpression Id [Token] [Token]
-    | T_Annotation Id [Annotation] Token
-    | T_Pipe Id String
-    | T_CoProc Id (Maybe String) Token
-    | T_CoProcBody Id Token
-    | T_Include Id Token
-    | T_SourceCommand Id Token Token
-    | T_BatsTest Id Token Token
-    deriving (Show)
+    | Inner_T_UnparsedIndex SourcePos String
+    | Inner_T_Assignment AssignmentMode String [t] t
+    | Inner_T_Backgrounded t
+    | Inner_T_Backticked [t]
+    | Inner_T_Bang
+    | Inner_T_Banged t
+    | Inner_T_BraceExpansion [t]
+    | Inner_T_BraceGroup [t]
+    | Inner_T_CLOBBER
+    | Inner_T_Case
+    | Inner_T_CaseExpression t [(CaseType, [t], [t])]
+    | Inner_T_Condition ConditionType t
+    | Inner_T_DGREAT
+    | Inner_T_DLESS
+    | Inner_T_DLESSDASH
+    | Inner_T_DSEMI
+    | Inner_T_Do
+    | Inner_T_DollarArithmetic t
+    | Inner_T_DollarBraced Bool t
+    | Inner_T_DollarBracket t
+    | Inner_T_DollarDoubleQuoted [t]
+    | Inner_T_DollarExpansion [t]
+    | Inner_T_DollarSingleQuoted String
+    | Inner_T_DollarBraceCommandExpansion [t]
+    | Inner_T_Done
+    | Inner_T_DoubleQuoted [t]
+    | Inner_T_EOF
+    | Inner_T_Elif
+    | Inner_T_Else
+    | Inner_T_Esac
+    | Inner_T_Extglob String [t]
+    | Inner_T_FdRedirect String t
+    | Inner_T_Fi
+    | Inner_T_For
+    | Inner_T_ForArithmetic t t t [t]
+    | Inner_T_ForIn String [t] [t]
+    | Inner_T_Function FunctionKeyword FunctionParentheses String t
+    | Inner_T_GREATAND
+    | Inner_T_Glob String
+    | Inner_T_Greater
+    | Inner_T_HereDoc Dashed Quoted String [t]
+    | Inner_T_HereString t
+    | Inner_T_If
+    | Inner_T_IfExpression [([t],[t])] [t]
+    | Inner_T_In
+    | Inner_T_IoFile t t
+    | Inner_T_IoDuplicate t String
+    | Inner_T_LESSAND
+    | Inner_T_LESSGREAT
+    | Inner_T_Lbrace
+    | Inner_T_Less
+    | Inner_T_Literal String
+    | Inner_T_Lparen
+    | Inner_T_NEWLINE
+    | Inner_T_NormalWord [t]
+    | Inner_T_OR_IF
+    | Inner_T_OrIf t t
+    | Inner_T_ParamSubSpecialChar String -- e.g. '%' in ${foo%bar}  or '/' in ${foo/bar/baz}
+    | Inner_T_Pipeline [t] [t] -- [Pipe separators] [Commands]
+    | Inner_T_ProcSub String [t]
+    | Inner_T_Rbrace
+    | Inner_T_Redirecting [t] t
+    | Inner_T_Rparen
+    | Inner_T_Script t [t] -- Shebang T_Literal, followed by script.
+    | Inner_T_Select
+    | Inner_T_SelectIn String [t] [t]
+    | Inner_T_Semi
+    | Inner_T_SimpleCommand [t] [t]
+    | Inner_T_SingleQuoted String
+    | Inner_T_Subshell [t]
+    | Inner_T_Then
+    | Inner_T_Until
+    | Inner_T_UntilExpression [t] [t]
+    | Inner_T_While
+    | Inner_T_WhileExpression [t] [t]
+    | Inner_T_Annotation [Annotation] t
+    | Inner_T_Pipe String
+    | Inner_T_CoProc (Maybe Token) t
+    | Inner_T_CoProcBody t
+    | Inner_T_Include t
+    | Inner_T_SourceCommand t t
+    | Inner_T_BatsTest String t
+    deriving (Show, Eq, Functor, Foldable, Traversable)
 
 data Annotation =
-    DisableComment Integer
+    DisableComment Integer Integer -- [from, to)
     | EnableComment String
     | SourceOverride String
     | ShellOverride String
     | SourcePath String
+    | ExternalSources Bool
+    | ExtendedAnalysis Bool
     deriving (Show, Eq)
 data ConditionType = DoubleBracket | SingleBracket deriving (Show, Eq)
 
--- This is an abomination.
-tokenEquals :: Token -> Token -> Bool
-tokenEquals a b = kludge a == kludge b
-    where kludge s = Re.subRegex (Re.mkRegex "\\(Id [0-9]+\\)") (show s) "(Id 0)"
+pattern T_AND_IF id = OuterToken id Inner_T_AND_IF
+pattern T_Bang id = OuterToken id Inner_T_Bang
+pattern T_Case id = OuterToken id Inner_T_Case
+pattern TC_Empty id typ = OuterToken id (Inner_TC_Empty typ)
+pattern T_CLOBBER id = OuterToken id Inner_T_CLOBBER
+pattern T_DGREAT id = OuterToken id Inner_T_DGREAT
+pattern T_DLESS id = OuterToken id Inner_T_DLESS
+pattern T_DLESSDASH id = OuterToken id Inner_T_DLESSDASH
+pattern T_Do id = OuterToken id Inner_T_Do
+pattern T_DollarSingleQuoted id str = OuterToken id (Inner_T_DollarSingleQuoted str)
+pattern T_Done id = OuterToken id Inner_T_Done
+pattern T_DSEMI id = OuterToken id Inner_T_DSEMI
+pattern T_Elif id = OuterToken id Inner_T_Elif
+pattern T_Else id = OuterToken id Inner_T_Else
+pattern T_EOF id = OuterToken id Inner_T_EOF
+pattern T_Esac id = OuterToken id Inner_T_Esac
+pattern T_Fi id = OuterToken id Inner_T_Fi
+pattern T_For id = OuterToken id Inner_T_For
+pattern T_Glob id str = OuterToken id (Inner_T_Glob str)
+pattern T_GREATAND id = OuterToken id Inner_T_GREATAND
+pattern T_Greater id = OuterToken id Inner_T_Greater
+pattern T_If id = OuterToken id Inner_T_If
+pattern T_In id = OuterToken id Inner_T_In
+pattern T_Lbrace id = OuterToken id Inner_T_Lbrace
+pattern T_Less id = OuterToken id Inner_T_Less
+pattern T_LESSAND id = OuterToken id Inner_T_LESSAND
+pattern T_LESSGREAT id = OuterToken id Inner_T_LESSGREAT
+pattern T_Literal id str = OuterToken id (Inner_T_Literal str)
+pattern T_Lparen id = OuterToken id Inner_T_Lparen
+pattern T_NEWLINE id = OuterToken id Inner_T_NEWLINE
+pattern T_OR_IF id = OuterToken id Inner_T_OR_IF
+pattern T_ParamSubSpecialChar id str = OuterToken id (Inner_T_ParamSubSpecialChar str)
+pattern T_Pipe id str = OuterToken id (Inner_T_Pipe str)
+pattern T_Rbrace id = OuterToken id Inner_T_Rbrace
+pattern T_Rparen id = OuterToken id Inner_T_Rparen
+pattern T_Select id = OuterToken id Inner_T_Select
+pattern T_Semi id = OuterToken id Inner_T_Semi
+pattern T_SingleQuoted id str = OuterToken id (Inner_T_SingleQuoted str)
+pattern T_Then id = OuterToken id Inner_T_Then
+pattern T_UnparsedIndex id pos str = OuterToken id (Inner_T_UnparsedIndex pos str)
+pattern T_Until id = OuterToken id Inner_T_Until
+pattern T_While id = OuterToken id Inner_T_While
+pattern TA_Assignment id op t1 t2 = OuterToken id (Inner_TA_Assignment op t1 t2)
+pattern TA_Binary id op t1 t2 = OuterToken id (Inner_TA_Binary op t1 t2)
+pattern TA_Expansion id t = OuterToken id (Inner_TA_Expansion t)
+pattern T_AndIf id t u = OuterToken id (Inner_T_AndIf t u)
+pattern T_Annotation id anns t = OuterToken id (Inner_T_Annotation anns t)
+pattern T_Arithmetic id c = OuterToken id (Inner_T_Arithmetic c)
+pattern T_Array id t = OuterToken id (Inner_T_Array t)
+pattern TA_Sequence id l = OuterToken id (Inner_TA_Sequence l)
+pattern TA_Parenthesis id t = OuterToken id (Inner_TA_Parenthesis t)
+pattern T_Assignment id mode var indices value = OuterToken id (Inner_T_Assignment mode var indices value)
+pattern TA_Trinary id t1 t2 t3 = OuterToken id (Inner_TA_Trinary t1 t2 t3)
+pattern TA_Unary id op t1 = OuterToken id (Inner_TA_Unary op t1)
+pattern TA_Variable id str t = OuterToken id (Inner_TA_Variable str t)
+pattern T_Backgrounded id l = OuterToken id (Inner_T_Backgrounded l)
+pattern T_Backticked id list = OuterToken id (Inner_T_Backticked list)
+pattern T_Banged id l = OuterToken id (Inner_T_Banged l)
+pattern T_BatsTest id name t = OuterToken id (Inner_T_BatsTest name t)
+pattern T_BraceExpansion id list = OuterToken id (Inner_T_BraceExpansion list)
+pattern T_BraceGroup id l = OuterToken id (Inner_T_BraceGroup l)
+pattern TC_And id typ str t1 t2 = OuterToken id (Inner_TC_And typ str t1 t2)
+pattern T_CaseExpression id word cases = OuterToken id (Inner_T_CaseExpression word cases)
+pattern TC_Binary id typ op lhs rhs = OuterToken id (Inner_TC_Binary typ op lhs rhs)
+pattern TC_Group id typ token = OuterToken id (Inner_TC_Group typ token)
+pattern TC_Nullary id typ token = OuterToken id (Inner_TC_Nullary typ token)
+pattern T_Condition id typ token = OuterToken id (Inner_T_Condition typ token)
+pattern T_CoProcBody id t = OuterToken id (Inner_T_CoProcBody t)
+pattern T_CoProc id var body = OuterToken id (Inner_T_CoProc var body)
+pattern TC_Or id typ str t1 t2 = OuterToken id (Inner_TC_Or typ str t1 t2)
+pattern TC_Unary id typ op token = OuterToken id (Inner_TC_Unary typ op token)
+pattern T_DollarArithmetic id c = OuterToken id (Inner_T_DollarArithmetic c)
+pattern T_DollarBraceCommandExpansion id list = OuterToken id (Inner_T_DollarBraceCommandExpansion list)
+pattern T_DollarBraced id braced op = OuterToken id (Inner_T_DollarBraced braced op)
+pattern T_DollarBracket id c = OuterToken id (Inner_T_DollarBracket c)
+pattern T_DollarDoubleQuoted id list = OuterToken id (Inner_T_DollarDoubleQuoted list)
+pattern T_DollarExpansion id list = OuterToken id (Inner_T_DollarExpansion list)
+pattern T_DoubleQuoted id list = OuterToken id (Inner_T_DoubleQuoted list)
+pattern T_Extglob id str l = OuterToken id (Inner_T_Extglob str l)
+pattern T_FdRedirect id v t = OuterToken id (Inner_T_FdRedirect v t)
+pattern T_ForArithmetic id a b c group = OuterToken id (Inner_T_ForArithmetic a b c group)
+pattern T_ForIn id v w l = OuterToken id (Inner_T_ForIn v w l)
+pattern T_Function id a b name body = OuterToken id (Inner_T_Function a b name body)
+pattern T_HereDoc id d q str l = OuterToken id (Inner_T_HereDoc d q str l)
+pattern T_HereString id word = OuterToken id (Inner_T_HereString word)
+pattern T_IfExpression id conditions elses = OuterToken id (Inner_T_IfExpression conditions elses)
+pattern T_Include id script = OuterToken id (Inner_T_Include script)
+pattern T_IndexedElement id indices t = OuterToken id (Inner_T_IndexedElement indices t)
+pattern T_IoDuplicate id op num = OuterToken id (Inner_T_IoDuplicate op num)
+pattern T_IoFile id op file = OuterToken id (Inner_T_IoFile op file)
+pattern T_NormalWord id list = OuterToken id (Inner_T_NormalWord list)
+pattern T_OrIf id t u = OuterToken id (Inner_T_OrIf t u)
+pattern T_Pipeline id l1 l2 = OuterToken id (Inner_T_Pipeline l1 l2)
+pattern T_ProcSub id typ l = OuterToken id (Inner_T_ProcSub typ l)
+pattern T_Redirecting id redirs cmd = OuterToken id (Inner_T_Redirecting redirs cmd)
+pattern T_Script id shebang list = OuterToken id (Inner_T_Script shebang list)
+pattern T_SelectIn id v w l = OuterToken id (Inner_T_SelectIn v w l)
+pattern T_SimpleCommand id vars cmds = OuterToken id (Inner_T_SimpleCommand vars cmds)
+pattern T_SourceCommand id includer t_include = OuterToken id (Inner_T_SourceCommand includer t_include)
+pattern T_Subshell id l = OuterToken id (Inner_T_Subshell l)
+pattern T_UntilExpression id c l = OuterToken id (Inner_T_UntilExpression c l)
+pattern T_WhileExpression id c l = OuterToken id (Inner_T_WhileExpression c l)
+
+{-# COMPLETE T_AND_IF, T_Bang, T_Case, TC_Empty, T_CLOBBER, T_DGREAT, T_DLESS, T_DLESSDASH, T_Do, T_DollarSingleQuoted, T_Done, T_DSEMI, T_Elif, T_Else, T_EOF, T_Esac, T_Fi, T_For, T_Glob, T_GREATAND, T_Greater, T_If, T_In, T_Lbrace, T_Less, T_LESSAND, T_LESSGREAT, T_Literal, T_Lparen, T_NEWLINE, T_OR_IF, T_ParamSubSpecialChar, T_Pipe, T_Rbrace, T_Rparen, T_Select, T_Semi, T_SingleQuoted, T_Then, T_UnparsedIndex, T_Until, T_While, TA_Assignment, TA_Binary, TA_Expansion, T_AndIf, T_Annotation, T_Arithmetic, T_Array, TA_Sequence, TA_Parenthesis, T_Assignment, TA_Trinary, TA_Unary, TA_Variable, T_Backgrounded, T_Backticked, T_Banged, T_BatsTest, T_BraceExpansion, T_BraceGroup, TC_And, T_CaseExpression, TC_Binary, TC_Group, TC_Nullary, T_Condition, T_CoProcBody, T_CoProc, TC_Or, TC_Unary, T_DollarArithmetic, T_DollarBraceCommandExpansion, T_DollarBraced, T_DollarBracket, T_DollarDoubleQuoted, T_DollarExpansion, T_DoubleQuoted, T_Extglob, T_FdRedirect, T_ForArithmetic, T_ForIn, T_Function, T_HereDoc, T_HereString, T_IfExpression, T_Include, T_IndexedElement, T_IoDuplicate, T_IoFile, T_NormalWord, T_OrIf, T_Pipeline, T_ProcSub, T_Redirecting, T_Script, T_SelectIn, T_SimpleCommand, T_SourceCommand, T_Subshell, T_UntilExpression, T_WhileExpression #-}
 
 instance Eq Token where
-    (==) = tokenEquals
+    OuterToken _ a == OuterToken _ b = a == b
 
 analyze :: Monad m => (Token -> m ()) -> (Token -> m ()) -> (Token -> m Token) -> Token -> m Token
 analyze f g i =
     round
   where
-    round t = do
+    round t@(OuterToken id it) = do
         f t
-        newT <- delve t
+        newIt <- traverse round it
         g t
-        i newT
-    roundAll = mapM round
-
-    dl l v = do
-        x <- roundAll l
-        return $ v x
-    dll l m v = do
-        x <- roundAll l
-        y <- roundAll m
-        return $ v x y
-    d1 t v = do
-        x <- round t
-        return $ v x
-    d2 t1 t2 v = do
-        x <- round t1
-        y <- round t2
-        return $ v x y
-
-    delve (T_NormalWord id list) = dl list $ T_NormalWord id
-    delve (T_DoubleQuoted id list) = dl list $ T_DoubleQuoted id
-    delve (T_DollarDoubleQuoted id list) = dl list $ T_DollarDoubleQuoted id
-    delve (T_DollarExpansion id list) = dl list $ T_DollarExpansion id
-    delve (T_DollarBraceCommandExpansion id list) = dl list $ T_DollarBraceCommandExpansion id
-    delve (T_BraceExpansion id list) = dl list $ T_BraceExpansion id
-    delve (T_Backticked id list) = dl list $ T_Backticked id
-    delve (T_DollarArithmetic id c) = d1 c $ T_DollarArithmetic id
-    delve (T_DollarBracket id c) = d1 c $ T_DollarBracket id
-    delve (T_IoFile id op file) = d2 op file $ T_IoFile id
-    delve (T_IoDuplicate id op num) = d1 op $ \x -> T_IoDuplicate id x num
-    delve (T_HereString id word) = d1 word $ T_HereString id
-    delve (T_FdRedirect id v t) = d1 t $ T_FdRedirect id v
-    delve (T_Assignment id mode var indices value) = do
-        a <- roundAll indices
-        b <- round value
-        return $ T_Assignment id mode var a b
-    delve (T_Array id t) = dl t $ T_Array id
-    delve (T_IndexedElement id indices t) = do
-        a <- roundAll indices
-        b <- round t
-        return $ T_IndexedElement id a b
-    delve (T_Redirecting id redirs cmd) = do
-        a <- roundAll redirs
-        b <- round cmd
-        return $ T_Redirecting id a b
-    delve (T_SimpleCommand id vars cmds) = dll vars cmds $ T_SimpleCommand id
-    delve (T_Pipeline id l1 l2) = dll l1 l2 $ T_Pipeline id
-    delve (T_Banged id l) = d1 l $ T_Banged id
-    delve (T_AndIf id t u) = d2 t u $ T_AndIf id
-    delve (T_OrIf id t u) = d2 t u $ T_OrIf id
-    delve (T_Backgrounded id l) = d1 l $ T_Backgrounded id
-    delve (T_Subshell id l) = dl l $ T_Subshell id
-    delve (T_ProcSub id typ l) = dl l $ T_ProcSub id typ
-    delve (T_Arithmetic id c) = d1 c $ T_Arithmetic id
-    delve (T_IfExpression id conditions elses) = do
-        newConds <- mapM (\(c, t) -> do
-                            x <- mapM round c
-                            y <- mapM round t
-                            return (x,y)
-                    ) conditions
-        newElses <- roundAll elses
-        return $ T_IfExpression id newConds newElses
-    delve (T_BraceGroup id l) = dl l $ T_BraceGroup id
-    delve (T_WhileExpression id c l) = dll c l $ T_WhileExpression id
-    delve (T_UntilExpression id c l) = dll c l $ T_UntilExpression id
-    delve (T_ForIn id v w l) = dll w l $ T_ForIn id v
-    delve (T_SelectIn id v w l) = dll w l $ T_SelectIn id v
-    delve (T_CaseExpression id word cases) = do
-        newWord <- round word
-        newCases <- mapM (\(o, c, t) -> do
-                            x <- mapM round c
-                            y <- mapM round t
-                            return (o, x,y)
-                        ) cases
-        return $ T_CaseExpression id newWord newCases
-
-    delve (T_ForArithmetic id a b c group) = do
-        x <- round a
-        y <- round b
-        z <- round c
-        list <- mapM round group
-        return $ T_ForArithmetic id x y z list
-
-    delve (T_Script id s l) = dl l $ T_Script id s
-    delve (T_Function id a b name body) = d1 body $ T_Function id a b name
-    delve (T_Condition id typ token) = d1 token $ T_Condition id typ
-    delve (T_Extglob id str l) = dl l $ T_Extglob id str
-    delve (T_DollarBraced id braced op) = d1 op $ T_DollarBraced id braced
-    delve (T_HereDoc id d q str l) = dl l $ T_HereDoc id d q str
-
-    delve (TC_And id typ str t1 t2) = d2 t1 t2 $ TC_And id typ str
-    delve (TC_Or id typ str t1 t2) = d2 t1 t2 $ TC_Or id typ str
-    delve (TC_Group id typ token) = d1 token $ TC_Group id typ
-    delve (TC_Binary id typ op lhs rhs) = d2 lhs rhs $ TC_Binary id typ op
-    delve (TC_Unary id typ op token) = d1 token $ TC_Unary id typ op
-    delve (TC_Nullary id typ token) = d1 token $ TC_Nullary id typ
-
-    delve (TA_Binary id op t1 t2) = d2 t1 t2 $ TA_Binary id op
-    delve (TA_Assignment id op t1 t2) = d2 t1 t2 $ TA_Assignment id op
-    delve (TA_Unary id op t1) = d1 t1 $ TA_Unary id op
-    delve (TA_Sequence id l) = dl l $ TA_Sequence id
-    delve (TA_Trinary id t1 t2 t3) = do
-        a <- round t1
-        b <- round t2
-        c <- round t3
-        return $ TA_Trinary id a b c
-    delve (TA_Expansion id t) = dl t $ TA_Expansion id
-    delve (TA_Variable id str t) = dl t $ TA_Variable id str
-    delve (T_Annotation id anns t) = d1 t $ T_Annotation id anns
-    delve (T_CoProc id var body) = d1 body $ T_CoProc id var
-    delve (T_CoProcBody id t) = d1 t $ T_CoProcBody id
-    delve (T_Include id script) = d1 script $ T_Include id
-    delve (T_SourceCommand id includer t_include) = d2 includer t_include $ T_SourceCommand id
-    delve (T_BatsTest id name t) = d2 name t $ T_BatsTest id
-    delve t = return t
+        i (OuterToken id newIt)
 
 getId :: Token -> Id
-getId t = case t of
-        T_AND_IF id  -> id
-        T_OR_IF id  -> id
-        T_DSEMI id  -> id
-        T_Semi id  -> id
-        T_DLESS id  -> id
-        T_DGREAT id  -> id
-        T_LESSAND id  -> id
-        T_GREATAND id  -> id
-        T_LESSGREAT id  -> id
-        T_DLESSDASH id  -> id
-        T_CLOBBER id  -> id
-        T_If id  -> id
-        T_Then id  -> id
-        T_Else id  -> id
-        T_Elif id  -> id
-        T_Fi id  -> id
-        T_Do id  -> id
-        T_Done id  -> id
-        T_Case id  -> id
-        T_Esac id  -> id
-        T_While id  -> id
-        T_Until id  -> id
-        T_For id  -> id
-        T_Select id  -> id
-        T_Lbrace id  -> id
-        T_Rbrace id  -> id
-        T_Lparen id  -> id
-        T_Rparen id  -> id
-        T_Bang id  -> id
-        T_In  id  -> id
-        T_NEWLINE id  -> id
-        T_EOF id  -> id
-        T_Less id  -> id
-        T_Greater id  -> id
-        T_SingleQuoted id _  -> id
-        T_Literal id _  -> id
-        T_NormalWord id _  -> id
-        T_DoubleQuoted id _  -> id
-        T_DollarExpansion id _  -> id
-        T_DollarBraced id _ _ -> id
-        T_DollarArithmetic id _  -> id
-        T_BraceExpansion id _  -> id
-        T_ParamSubSpecialChar id _ -> id
-        T_DollarBraceCommandExpansion id _  -> id
-        T_IoFile id _ _  -> id
-        T_IoDuplicate id _ _  -> id
-        T_HereDoc id _ _ _ _ -> id
-        T_HereString id _  -> id
-        T_FdRedirect id _ _  -> id
-        T_Assignment id _ _ _ _  -> id
-        T_Array id _  -> id
-        T_IndexedElement id _ _  -> id
-        T_Redirecting id _ _  -> id
-        T_SimpleCommand id _ _  -> id
-        T_Pipeline id _ _  -> id
-        T_Banged id _  -> id
-        T_AndIf id _ _ -> id
-        T_OrIf id _ _ -> id
-        T_Backgrounded id _  -> id
-        T_IfExpression id _ _  -> id
-        T_Subshell id _  -> id
-        T_BraceGroup id _  -> id
-        T_WhileExpression id _ _  -> id
-        T_UntilExpression id _ _  -> id
-        T_ForIn id _ _ _  -> id
-        T_SelectIn id _ _ _  -> id
-        T_CaseExpression id _ _ -> id
-        T_Function id _ _ _ _  -> id
-        T_Arithmetic id _  -> id
-        T_Script id _ _  -> id
-        T_Condition id _ _  -> id
-        T_Extglob id _ _ -> id
-        T_Backticked id _ -> id
-        TC_And id _ _ _ _  -> id
-        TC_Or id _ _ _ _  -> id
-        TC_Group id _ _  -> id
-        TC_Binary id _ _ _ _  -> id
-        TC_Unary id _ _ _  -> id
-        TC_Nullary id _ _  -> id
-        TA_Binary id _ _ _  -> id
-        TA_Assignment id _ _ _  -> id
-        TA_Unary id _ _  -> id
-        TA_Sequence id _  -> id
-        TA_Trinary id _ _ _  -> id
-        TA_Expansion id _  -> id
-        T_ProcSub id _ _ -> id
-        T_Glob id _ -> id
-        T_ForArithmetic id _ _ _ _ -> id
-        T_DollarSingleQuoted id _ -> id
-        T_DollarDoubleQuoted id _ -> id
-        T_DollarBracket id _ -> id
-        T_Annotation id _ _ -> id
-        T_Pipe id _ -> id
-        T_CoProc id _ _ -> id
-        T_CoProcBody id _ -> id
-        T_Include id _ -> id
-        T_SourceCommand id _ _ -> id
-        T_UnparsedIndex id _ _ -> id
-        TC_Empty id _ -> id
-        TA_Variable id _ _ -> id
-        T_BatsTest id _ _ -> id
+getId (OuterToken id _) = id
 
 blank :: Monad m => Token -> m ()
 blank = const $ return ()

src/ShellCheck/ASTLib.hs

@@ -1,5 +1,5 @@
 {-
-    Copyright 2012-2019 Vidar Holen
+    Copyright 2012-2021 Vidar Holen
 
     This file is part of ShellCheck.
     https://www.shellcheck.net
@@ -17,16 +17,27 @@
     You should have received a copy of the GNU General Public License
     along with this program.  If not, see <https://www.gnu.org/licenses/>.
 -}
+{-# LANGUAGE TemplateHaskell #-}
 module ShellCheck.ASTLib where
 
 import ShellCheck.AST
+import ShellCheck.Prelude
+import ShellCheck.Regex
 
 import Control.Monad.Writer
 import Control.Monad
 import Data.Char
 import Data.Functor
+import Data.Functor.Identity
 import Data.List
 import Data.Maybe
+import qualified Data.List.NonEmpty as NE
+import qualified Data.Map as Map
+import Numeric (showHex)
+
+import Test.QuickCheck
+
+arguments (T_SimpleCommand _ _ (cmd:args)) = args
 
 -- Is this a type of loop?
 isLoop t = case t of
@@ -46,13 +57,32 @@ willSplit x =
     T_BraceExpansion {} -> True
     T_Glob {} -> True
     T_Extglob {} -> True
+    T_DoubleQuoted _ l -> any willBecomeMultipleArgs l
     T_NormalWord _ l -> any willSplit l
     _ -> False
 
-isGlob T_Extglob {} = True
-isGlob T_Glob {} = True
-isGlob (T_NormalWord _ l) = any isGlob l
-isGlob _ = False
+isGlob t = case t of
+    T_Extglob {} -> True
+    T_Glob {} -> True
+    T_NormalWord _ l -> any isGlob l || hasSplitRange l
+    _ -> False
+  where
+    -- foo[x${var}y] gets parsed as foo,[,x,$var,y],
+    -- so check if there's such an interval
+    hasSplitRange l =
+        let afterBracket = dropWhile (not . isHalfOpenRange) l
+        in any isClosingRange afterBracket
+
+    isHalfOpenRange t =
+        case t of
+            T_Literal _ "[" -> True
+            _ -> False
+
+    isClosingRange t =
+        case t of
+            T_Literal _ str -> ']' `elem` str
+            _ -> False
+
 
 -- Is this shell word a constant?
 isConstant token =
@@ -110,7 +140,7 @@ getFlagsUntil stopCondition (T_SimpleCommand _ _ (_:args)) =
     flag (x, '-':'-':arg) = [ (x, takeWhile (/= '=') arg) ]
     flag (x, '-':args) = map (\v -> (x, [v])) args
     flag (x, _) = [ (x, "") ]
-getFlagsUntil _ _ = error "Internal shellcheck error, please report! (getFlags on non-command)"
+getFlagsUntil _ _ = error $ pleaseReport "getFlags on non-command"
 
 -- Get all flags in a GNU way, up until --
 getAllFlags :: Token -> [(Token, String)]
@@ -128,30 +158,146 @@ isFlag token =
         _ -> False
 
 -- Is this token a flag where the - is unquoted?
-isUnquotedFlag token = fromMaybe False $ do
-    str <- getLeadingUnquotedString token
-    return $ "-" `isPrefixOf` str
+isUnquotedFlag token =
+    case getLeadingUnquotedString token of
+        Just ('-':_) -> True
+        _ -> False
+
+-- getGnuOpts "erd:u:" will parse a list of arguments tokens like `read`
+--     -re -d : -u 3 bar
+-- into
+--     Just [("r", (-re, -re)), ("e", (-re, -re)), ("d", (-d,:)), ("u", (-u,3)), ("", (bar,bar))]
+--
+-- Each string flag maps to a tuple of (flag, argument), where argument=flag if it
+-- doesn't take a specific one.
+--
+-- Any unrecognized flag will result in Nothing. The exception is if arbitraryLongOpts
+-- is set, in which case --anything will map to "anything".
+getGnuOpts :: String -> [Token] -> Maybe [(String, (Token, Token))]
+getGnuOpts str args = getOpts (True, False) str [] args
+
+-- As above, except the first non-arg string will treat the rest as arguments
+getBsdOpts :: String -> [Token] -> Maybe [(String, (Token, Token))]
+getBsdOpts str args = getOpts (False, False) str [] args
+
+-- Tests for this are in Commands.hs where it's more frequently used
+getOpts ::
+    -- Behavioral config: gnu style, allow arbitrary long options
+    (Bool, Bool)
+    -- A getopts style string
+    -> String
+    -- List of long options and whether they take arguments
+    -> [(String, Bool)]
+    -- List of arguments (excluding command)
+    -> [Token]
+    -- List of flags to tuple of (optionToken, valueToken)
+    -> Maybe [(String, (Token, Token))]
+
+getOpts (gnu, arbitraryLongOpts) string longopts args = process args
+  where
+    flagList (c:':':rest) = ([c], True) : flagList rest
+    flagList (c:rest)     = ([c], False) : flagList rest
+    flagList []           = longopts
+    flagMap = Map.fromList $ ("", False) : flagList string
+
+    process [] = return []
+    process (token:rest) = do
+        case getLiteralStringDef "\0" token of
+            "--" -> return $ listToArgs rest
+            '-':'-':word -> do
+                let (name, arg) = span (/= '=') word
+                needsArg <-
+                    if arbitraryLongOpts
+                    then return $ Map.findWithDefault False name flagMap
+                    else Map.lookup name flagMap
+
+                if needsArg && null arg
+                  then
+                    case rest of
+                        (arg:rest2) -> do
+                            more <- process rest2
+                            return $ (name, (token, arg)) : more
+                        _ -> fail "Missing arg"
+                  else do
+                    more <- process rest
+                    -- Consider splitting up token to get arg
+                    return $ (name, (token, token)) : more
+            '-':opts -> shortToOpts opts token rest
+            arg ->
+                if gnu
+                then do
+                    more <- process rest
+                    return $ ("", (token, token)):more
+                else return $ listToArgs (token:rest)
+
+    shortToOpts opts token args =
+        case opts of
+            c:rest -> do
+                needsArg <- Map.lookup [c] flagMap
+                case () of
+                    _ | needsArg && null rest -> do
+                        (next:restArgs) <- return args
+                        more <- process restArgs
+                        return $ ([c], (token, next)):more
+                    _ | needsArg -> do
+                        more <- process args
+                        return $ ([c], (token, token)):more
+                    _ -> do
+                        more <- shortToOpts rest token args
+                        return $ ([c], (token, token)):more
+            [] -> process args
+
+    listToArgs = map (\x -> ("", (x, x)))
+
+
+-- Generic getOpts that doesn't rely on a format string, but may also be inaccurate.
+-- This provides a best guess interpretation instead of failing when new options are added.
+--
+--    "--" is treated as end of arguments
+--    "--anything[=foo]" is treated as a long option without argument
+--    "-any" is treated as -a -n -y, with the next arg as an option to -y unless it starts with -
+--    anything else is an argument
+getGenericOpts :: [Token] -> [(String, (Token, Token))]
+getGenericOpts = process
+  where
+    process (token:rest) =
+        case getLiteralStringDef "\0" token of
+            "--" -> map (\c -> ("", (c,c))) rest
+            '-':'-':word -> (takeWhile (`notElem` "\0=") word, (token, token)) : process rest
+            '-':optString ->
+                let opts = takeWhile (/= '\0') optString
+                in
+                    case rest of
+                        next:_ | "-" `isPrefixOf` getLiteralStringDef "\0" next  ->
+                            map (\c -> ([c], (token, token))) opts ++ process rest
+                        next:remainder ->
+                            case reverse opts of
+                                last:initial ->
+                                    map (\c -> ([c], (token, token))) (reverse initial)
+                                        ++ [([last], (token, next))]
+                                        ++ process remainder
+                                [] -> process remainder
+                        [] -> map (\c -> ([c], (token, token))) opts
+            _ -> ("", (token, token)) : process rest
+    process [] = []
 
--- Given a T_DollarBraced, return a simplified version of the string contents.
-bracedString (T_DollarBraced _ _ l) = concat $ oversimplify l
-bracedString _ = error "Internal shellcheck error, please report! (bracedString on non-variable)"
 
 -- Is this an expansion of multiple items of an array?
-isArrayExpansion t@(T_DollarBraced _ _ _) =
-    let string = bracedString t in
+isArrayExpansion (T_DollarBraced _ _ l) =
+    let string = concat $ oversimplify l in
         "@" `isPrefixOf` string ||
             not ("#" `isPrefixOf` string) && "[@]" `isInfixOf` string
 isArrayExpansion _ = False
 
 -- Is it possible that this arg becomes multiple args?
-mayBecomeMultipleArgs t = willBecomeMultipleArgs t || f t
+mayBecomeMultipleArgs t = willBecomeMultipleArgs t || f False t
   where
-    f t@(T_DollarBraced _ _ _) =
-        let string = bracedString t in
-            "!" `isPrefixOf` string
-    f (T_DoubleQuoted _ parts) = any f parts
-    f (T_NormalWord _ parts) = any f parts
-    f _ = False
+    f quoted (T_DollarBraced _ _ l) =
+        let string = concat $ oversimplify l in
+            not quoted || "!" `isPrefixOf` string
+    f quoted (T_DoubleQuoted _ parts) = any (f True) parts
+    f quoted (T_NormalWord _ parts) = any (f quoted) parts
+    f _ _ = False
 
 -- Is it certain that this word will becomes multiple words?
 willBecomeMultipleArgs t = willConcatInAssignment t || f t
@@ -159,7 +305,6 @@ willBecomeMultipleArgs t = willConcatInAssignment t || f t
     f T_Extglob {} = True
     f T_Glob {} = True
     f T_BraceExpansion {} = True
-    f (T_DoubleQuoted _ parts) = any f parts
     f (T_NormalWord _ parts) = any f parts
     f _ = False
 
@@ -175,9 +320,13 @@ willConcatInAssignment token =
 getLiteralString :: Token -> Maybe String
 getLiteralString = getLiteralStringExt (const Nothing)
 
+-- Definitely get a literal string, with a given default for all non-literals
+getLiteralStringDef :: String -> Token -> String
+getLiteralStringDef x = runIdentity . getLiteralStringExt (const $ return x)
+
 -- Definitely get a literal string, skipping over all non-literals
 onlyLiteralString :: Token -> String
-onlyLiteralString = fromJust . getLiteralStringExt (const $ return "")
+onlyLiteralString = getLiteralStringDef ""
 
 -- Maybe get a literal string, but only if it's an unquoted argument.
 getUnquotedLiteral (T_NormalWord _ list) =
@@ -187,6 +336,12 @@ getUnquotedLiteral (T_NormalWord _ list) =
     str _ = Nothing
 getUnquotedLiteral _ = Nothing
 
+isQuotes t =
+    case t of
+        T_DoubleQuoted {} -> True
+        T_SingleQuoted {} -> True
+        _ -> False
+
 -- Get the last unquoted T_Literal in a word like "${var}foo"THIS
 -- or nothing if the word does not end in an unquoted literal.
 getTrailingUnquotedLiteral :: Token -> Maybe Token
@@ -205,8 +360,11 @@ getTrailingUnquotedLiteral t =
 getLeadingUnquotedString :: Token -> Maybe String
 getLeadingUnquotedString t =
     case t of
-        T_NormalWord _ ((T_Literal _ s) : _) -> return s
+        T_NormalWord _ ((T_Literal _ s) : rest) -> return $ s ++ from rest
         _ -> Nothing
+  where
+    from ((T_Literal _ s):rest) = s ++ from rest
+    from _ = ""
 
 -- Maybe get the literal string of this token and any globs in it.
 getGlobOrLiteralString = getLiteralStringExt f
@@ -214,9 +372,24 @@ getGlobOrLiteralString = getLiteralStringExt f
     f (T_Glob _ str) = return str
     f _ = Nothing
 
+
+prop_getLiteralString1 = getLiteralString (T_DollarSingleQuoted (Id 0) "\\x01") == Just "\1"
+prop_getLiteralString2 = getLiteralString (T_DollarSingleQuoted (Id 0) "\\xyz") == Just "\\xyz"
+prop_getLiteralString3 = getLiteralString (T_DollarSingleQuoted (Id 0) "\\x1") == Just "\x1"
+prop_getLiteralString4 = getLiteralString (T_DollarSingleQuoted (Id 0) "\\x1y") == Just "\x1y"
+prop_getLiteralString5 = getLiteralString (T_DollarSingleQuoted (Id 0) "\\xy") == Just "\\xy"
+prop_getLiteralString6 = getLiteralString (T_DollarSingleQuoted (Id 0) "\\x") == Just "\\x"
+prop_getLiteralString7 = getLiteralString (T_DollarSingleQuoted (Id 0) "\\1x") == Just "\1x"
+prop_getLiteralString8 = getLiteralString (T_DollarSingleQuoted (Id 0) "\\12x") == Just "\o12x"
+prop_getLiteralString9 = getLiteralString (T_DollarSingleQuoted (Id 0) "\\123x") == Just "\o123x"
+prop_getLiteralString10 = getLiteralString (T_DollarSingleQuoted (Id 0) "\\1234") == Just "\o123\&4"
+prop_getLiteralString11 = getLiteralString (T_DollarSingleQuoted (Id 0) "\\1") == Just "\1"
+prop_getLiteralString12 = getLiteralString (T_DollarSingleQuoted (Id 0) "\\12") == Just "\o12"
+prop_getLiteralString13 = getLiteralString (T_DollarSingleQuoted (Id 0) "\\123") == Just "\o123"
+
 -- Maybe get the literal value of a token, using a custom function
 -- to map unrecognized Tokens into strings.
-getLiteralStringExt :: (Token -> Maybe String) -> Token -> Maybe String
+getLiteralStringExt :: Monad m => (Token -> m String) -> Token -> m String
 getLiteralStringExt more = g
   where
     allInList = fmap concat . mapM g
@@ -246,14 +419,15 @@ getLiteralStringExt more = g
             '\\' -> '\\' : rest
             'x' ->
                 case cs of
-                    (x:y:more) ->
-                        if isHexDigit x && isHexDigit y
-                        then chr (16*(digitToInt x) + (digitToInt y)) : rest
-                        else '\\':c:rest
+                    (x:y:more) | isHexDigit x && isHexDigit y ->
+                        chr (16*(digitToInt x) + (digitToInt y)) : decodeEscapes more
+                    (x:more) | isHexDigit x ->
+                        chr (digitToInt x) : decodeEscapes more
+                    more -> '\\' : 'x' : decodeEscapes more
             _ | isOctDigit c ->
-                let digits = take 3 $ takeWhile isOctDigit (c:cs)
-                    num = parseOct digits
-                in (if num < 256 then chr num else '?') : rest
+                let (digits, more) = spanMax isOctDigit 3 (c:cs)
+                    num = (parseOct digits) `mod` 256
+                in (chr num) : decodeEscapes more
             _ -> '\\' : c : rest
       where
         rest = decodeEscapes cs
@@ -261,12 +435,54 @@ getLiteralStringExt more = g
           where
             f n "" = n
             f n (c:rest) = f (n * 8 + digitToInt c) rest
+        spanMax f n list =
+            let (first, second) = span f list
+                (prefix, suffix) = splitAt n first
+            in
+                (prefix, suffix ++ second)
     decodeEscapes (c:cs) = c : decodeEscapes cs
     decodeEscapes [] = []
 
 -- Is this token a string literal?
 isLiteral t = isJust $ getLiteralString t
 
+-- Is this token a string literal number?
+isLiteralNumber t = fromMaybe False $ do
+    s <- getLiteralString t
+    guard $ all isDigit s
+    return True
+
+-- Escape user data for messages.
+-- Messages generally avoid repeating user data, but sometimes it's helpful.
+e4m = escapeForMessage
+escapeForMessage :: String -> String
+escapeForMessage str = concatMap f str
+  where
+    f '\\' = "\\\\"
+    f '\n' = "\\n"
+    f '\r' = "\\r"
+    f '\t' = "\\t"
+    f '\x1B' = "\\e"
+    f c =
+        if shouldEscape c
+        then
+            if ord c < 256
+            then "\\x" ++ (pad0 2 $ toHex c)
+            else "\\U" ++ (pad0 4 $ toHex c)
+        else [c]
+
+    shouldEscape c =
+        (not $ isPrint c)
+        || (not (isAscii c) && not (isLetter c))
+
+    pad0 :: Int -> String -> String
+    pad0 n s =
+        let l = length s in
+            if l < n
+            then (replicate (n-l) '0') ++ s
+            else s
+    toHex :: Char -> String
+    toHex c = map toUpper $ showHex (ord c) ""
 
 -- Turn a NormalWord like foo="bar $baz" into a series of constituent elements like [foo=,bar ,$baz]
 getWordParts (T_NormalWord _ l)   = concatMap getWordParts l
@@ -295,25 +511,48 @@ getCommand t =
 
 -- Maybe get the command name string of a token representing a command
 getCommandName :: Token -> Maybe String
-getCommandName = fst . getCommandNameAndToken
+getCommandName = fst . getCommandNameAndToken False
+
+-- Maybe get the name+arguments of a command.
+getCommandArgv t = do
+    (T_SimpleCommand _ _ args@(_:_)) <- getCommand t
+    return args
 
 -- Get the command name token from a command, i.e.
 -- the token representing 'ls' in 'ls -la 2> foo'.
 -- If it can't be determined, return the original token.
-getCommandTokenOrThis = snd . getCommandNameAndToken
+getCommandTokenOrThis = snd . getCommandNameAndToken False
 
-getCommandNameAndToken :: Token -> (Maybe String, Token)
-getCommandNameAndToken t = fromMaybe (Nothing, t) $ do
-    (T_SimpleCommand _ _ (w:rest)) <- getCommand t
+-- Given a command, get the string and token that represents the command name.
+-- If direct, return the actual command (e.g. exec in 'exec ls')
+-- If not, return the logical command (e.g. 'ls' in 'exec ls')
+
+getCommandNameAndToken :: Bool -> Token -> (Maybe String, Token)
+getCommandNameAndToken direct t = fromMaybe (Nothing, t) $ do
+    cmd@(T_SimpleCommand _ _ (w:rest)) <- getCommand t
     s <- getLiteralString w
-    if "busybox" `isSuffixOf` s || "builtin" == s
-        then
-            case rest of
-                (applet:_) -> return (getLiteralString applet, applet)
-                _ -> return (Just s, w)
-        else
-            return (Just s, w)
-
+    return $ fromMaybe (Just s, w) $ do
+        guard $ not direct
+        actual <- getEffectiveCommandToken s cmd rest
+        return (getLiteralString actual, actual)
+  where
+    getEffectiveCommandToken str cmd args =
+        let
+            firstArg = do
+                arg <- listToMaybe args
+                guard . not $ isFlag arg
+                return arg
+        in
+            case str of
+                "busybox" -> firstArg
+                "builtin" -> firstArg
+                "command" -> firstArg
+                "run" -> firstArg -- Used by bats
+                "exec" -> do
+                    opts <- getBsdOpts "cla:" args
+                    (_, (t, _)) <- find (null . fst) opts
+                    return t
+                _ -> fail ""
 
 -- If a command substitution is a single command, get its name.
 --  $(date +%s) = Just "date"
@@ -330,7 +569,7 @@ getCommandNameFromExpansion t =
 
 -- Get the basename of a token representing a command
 getCommandBasename = fmap basename . getCommandName
-  where
+
 basename = reverse . takeWhile (/= '/') . reverse
 
 isAssignment t =
@@ -362,19 +601,23 @@ isFunctionLike t =
 isBraceExpansion t = case t of T_BraceExpansion {} -> True; _ -> False
 
 -- Get the lists of commands from tokens that contain them, such as
--- the body of while loops or branches of if statements.
+-- the conditions and bodies of while loops or branches of if statements.
 getCommandSequences :: Token -> [[Token]]
 getCommandSequences t =
     case t of
         T_Script _ _ cmds -> [cmds]
         T_BraceGroup _ cmds -> [cmds]
         T_Subshell _ cmds -> [cmds]
-        T_WhileExpression _ _ cmds -> [cmds]
-        T_UntilExpression _ _ cmds -> [cmds]
+        T_WhileExpression _ cond cmds -> [cond, cmds]
+        T_UntilExpression _ cond cmds -> [cond, cmds]
         T_ForIn _ _ _ cmds -> [cmds]
         T_ForArithmetic _ _ _ _ cmds -> [cmds]
-        T_IfExpression _ thens elses -> map snd thens ++ [elses]
+        T_IfExpression _ thens elses -> (concatMap (\(a,b) -> [a,b]) thens) ++ [elses]
         T_Annotation _ _ t -> getCommandSequences t
+
+        T_DollarExpansion _ cmds -> [cmds]
+        T_DollarBraceCommandExpansion _ cmds -> [cmds]
+        T_Backticked _ cmds -> [cmds]
         _ -> []
 
 -- Get a list of names of associative arrays
@@ -382,13 +625,13 @@ getAssociativeArrays t =
     nub . execWriter $ doAnalysis f t
   where
     f :: Token -> Writer [String] ()
-    f t@T_SimpleCommand {} = fromMaybe (return ()) $ do
+    f t@T_SimpleCommand {} = sequence_ $ do
         name <- getCommandName t
         let assocNames = ["declare","local","typeset"]
-        guard $ elem name assocNames
+        guard $ name `elem` assocNames
         let flags = getAllFlags t
-        guard $ elem "A" $ map snd flags
-        let args = map fst . filter ((==) "" . snd) $ flags
+        guard $ "A" `elem` map snd flags
+        let args = [arg | (arg, "") <- flags]
         let names = mapMaybe (getLiteralStringExt nameAssignments) args
         return $ tell names
     f _ = return ()
@@ -406,38 +649,36 @@ data PseudoGlob = PGAny | PGMany | PGChar Char
 
 -- Turn a word into a PG pattern, replacing all unknown/runtime values with
 -- PGMany.
-wordToPseudoGlob :: Token -> Maybe [PseudoGlob]
-wordToPseudoGlob word =
-    simplifyPseudoGlob . concat <$> mapM f (getWordParts word)
-  where
-    f x = case x of
-        T_Literal _ s -> return $ map PGChar s
-        T_SingleQuoted _ s -> return $ map PGChar s
-
-        T_DollarBraced {} -> return [PGMany]
-        T_DollarExpansion {} -> return [PGMany]
-        T_Backticked {} -> return [PGMany]
-
-        T_Glob _ "?" -> return [PGAny]
-        T_Glob _ ('[':_)  -> return [PGAny]
-        T_Glob {} -> return [PGMany]
-
-        T_Extglob {} -> return [PGMany]
-
-        _ -> return [PGMany]
+wordToPseudoGlob :: Token -> [PseudoGlob]
+wordToPseudoGlob = fromMaybe [PGMany] . wordToPseudoGlob' False
 
 -- Turn a word into a PG pattern, but only if we can preserve
 -- exact semantics.
 wordToExactPseudoGlob :: Token -> Maybe [PseudoGlob]
-wordToExactPseudoGlob word =
-    simplifyPseudoGlob . concat <$> mapM f (getWordParts word)
+wordToExactPseudoGlob = wordToPseudoGlob' True
+
+wordToPseudoGlob' :: Bool -> Token -> Maybe [PseudoGlob]
+wordToPseudoGlob' exact word =
+    simplifyPseudoGlob <$> toGlob word
   where
+    toGlob :: Token -> Maybe [PseudoGlob]
+    toGlob word =
+        case word of
+            T_NormalWord _ (T_Literal _ ('~':str):rest) -> do
+                guard $ not exact
+                let this = (PGMany : (map PGChar $ dropWhile (/= '/') str))
+                tail <- concat <$> (mapM f $ concatMap getWordParts rest)
+                return $ this ++ tail
+            _ -> concat <$> (mapM f $ getWordParts word)
+
     f x = case x of
         T_Literal _ s      -> return $ map PGChar s
         T_SingleQuoted _ s -> return $ map PGChar s
         T_Glob _ "?"       -> return [PGAny]
         T_Glob _ "*"       -> return [PGMany]
-        _ -> fail "Unknown token type"
+        T_Glob _ ('[':_) | not exact -> return [PGAny]
+        _ -> if exact then fail "" else return [PGMany]
+
 
 -- Reorder a PseudoGlob for more efficient matching, e.g.
 -- f?*?**g -> f??*g
@@ -487,8 +728,7 @@ pseudoGlobIsSuperSetof = matchable
     matchable (PGMany : rest) [] = matchable rest []
     matchable _ _ = False
 
-wordsCanBeEqual x y = fromMaybe True $
-    liftM2 pseudoGlobsCanOverlap (wordToPseudoGlob x) (wordToPseudoGlob y)
+wordsCanBeEqual x y = pseudoGlobsCanOverlap (wordToPseudoGlob x) (wordToPseudoGlob y)
 
 -- Is this an expansion that can be quoted,
 -- e.g. $(foo) `foo` $foo (but not {foo,})?
@@ -502,6 +742,11 @@ isCommandSubstitution t = case t of
     T_Backticked {} -> True
     _ -> False
 
+-- Is this an expansion that results in a simple string?
+isStringExpansion t = isCommandSubstitution t || case t of
+    T_DollarArithmetic {} -> True
+    T_DollarBraced {} -> not (isArrayExpansion t)
+    _ -> False
 
 -- Is this a T_Annotation that ignores a specific code?
 isAnnotationIgnoringCode code t =
@@ -509,5 +754,173 @@ isAnnotationIgnoringCode code t =
         T_Annotation _ anns _ -> any hasNum anns
         _ -> False
   where
-    hasNum (DisableComment ts) = code == ts
+    hasNum (DisableComment from to) = code >= from && code < to
     hasNum _                   = False
+
+prop_executableFromShebang1 = executableFromShebang "/bin/sh" == "sh"
+prop_executableFromShebang2 = executableFromShebang "/bin/bash" == "bash"
+prop_executableFromShebang3 = executableFromShebang "/usr/bin/env ksh" == "ksh"
+prop_executableFromShebang4 = executableFromShebang "/usr/bin/env -S foo=bar bash -x" == "bash"
+prop_executableFromShebang5 = executableFromShebang "/usr/bin/env --split-string=bash -x" == "bash"
+prop_executableFromShebang6 = executableFromShebang "/usr/bin/env --split-string=foo=bar bash -x" == "bash"
+prop_executableFromShebang7 = executableFromShebang "/usr/bin/env --split-string bash -x" == "bash"
+prop_executableFromShebang8 = executableFromShebang "/usr/bin/env --split-string foo=bar bash -x" == "bash"
+prop_executableFromShebang9 = executableFromShebang "/usr/bin/env foo=bar dash" == "dash"
+prop_executableFromShebang10 = executableFromShebang "/bin/busybox sh" == "busybox sh"
+prop_executableFromShebang11 = executableFromShebang "/bin/busybox ash" == "busybox ash"
+
+-- Get the shell executable from a string like '/usr/bin/env bash'
+executableFromShebang :: String -> String
+executableFromShebang = shellFor
+  where
+    re = mkRegex "/env +(-S|--split-string=?)? *(.*)"
+    shellFor s | s `matches` re =
+        case matchRegex re s of
+            Just [flag, shell] -> fromEnvArgs (words shell)
+            _ -> ""
+    shellFor sb =
+        case words sb of
+            [] -> ""
+            [x] -> basename x
+            (first:second:args) | basename first == "busybox" ->
+                case basename second of
+                   "sh" -> "busybox sh"
+                   "ash" -> "busybox ash"
+                   x -> x
+            (first:args) | basename first == "env" ->
+                fromEnvArgs args
+            (first:_) -> basename first
+
+    fromEnvArgs args = fromMaybe "" $ find (notElem '=') $ skipFlags args
+    basename s = reverse . takeWhile (/= '/') . reverse $ s
+    skipFlags = dropWhile ("-" `isPrefixOf`)
+
+
+-- Determining if a name is a variable
+isVariableStartChar x = x == '_' || isAsciiLower x || isAsciiUpper x
+isVariableChar x = isVariableStartChar x || isDigit x
+isSpecialVariableChar = (`elem` "*@#?-$!")
+variableNameRegex = mkRegex "[_a-zA-Z][_a-zA-Z0-9]*"
+
+prop_isVariableName1 = isVariableName "_fo123"
+prop_isVariableName2 = not $ isVariableName "4"
+prop_isVariableName3 = not $ isVariableName "test: "
+isVariableName (x:r) = isVariableStartChar x && all isVariableChar r
+isVariableName _     = False
+
+
+-- Get the variable name from an expansion like ${var:-foo}
+prop_getBracedReference1 = getBracedReference "foo" == "foo"
+prop_getBracedReference2 = getBracedReference "#foo" == "foo"
+prop_getBracedReference3 = getBracedReference "#" == "#"
+prop_getBracedReference4 = getBracedReference "##" == "#"
+prop_getBracedReference5 = getBracedReference "#!" == "!"
+prop_getBracedReference6 = getBracedReference "!#" == "#"
+prop_getBracedReference7 = getBracedReference "!foo#?" == "foo"
+prop_getBracedReference8 = getBracedReference "foo-bar" == "foo"
+prop_getBracedReference9 = getBracedReference "foo:-bar" == "foo"
+prop_getBracedReference10 = getBracedReference "foo: -1" == "foo"
+prop_getBracedReference11 = getBracedReference "!os*" == ""
+prop_getBracedReference11b = getBracedReference "!os@" == ""
+prop_getBracedReference12 = getBracedReference "!os?bar**" == ""
+prop_getBracedReference13 = getBracedReference "foo[bar]" == "foo"
+getBracedReference s = fromMaybe s $
+    nameExpansion s `mplus` takeName noPrefix `mplus` getSpecial noPrefix `mplus` getSpecial s
+  where
+    noPrefix = dropPrefix s
+    dropPrefix (c:rest) | c `elem` "!#" = rest
+    dropPrefix cs = cs
+    takeName s = do
+        let name = takeWhile isVariableChar s
+        guard . not $ null name
+        return name
+    getSpecial (c:_) | isSpecialVariableChar c = return [c]
+    getSpecial _ = fail "empty or not special"
+
+    nameExpansion ('!':next:rest) = do -- e.g. ${!foo*bar*}
+        guard $ isVariableChar next -- e.g. ${!@}
+        first <- find (not . isVariableChar) rest
+        guard $ first `elem` "*?@"
+        return ""
+    nameExpansion _ = Nothing
+
+-- Get the variable modifier like /a/b in ${var/a/b}
+prop_getBracedModifier1 = getBracedModifier "foo:bar:baz" == ":bar:baz"
+prop_getBracedModifier2 = getBracedModifier "!var:-foo" == ":-foo"
+prop_getBracedModifier3 = getBracedModifier "foo[bar]" == "[bar]"
+prop_getBracedModifier4 = getBracedModifier "foo[@]@Q" == "[@]@Q"
+prop_getBracedModifier5 = getBracedModifier "@@Q" == "@Q"
+getBracedModifier s = headOrDefault "" $ do
+    let var = getBracedReference s
+    a <- dropModifier s
+    dropPrefix var a
+  where
+    dropPrefix [] t        = return t
+    dropPrefix (a:b) (c:d) | a == c = dropPrefix b d
+    dropPrefix _ _         = []
+
+    dropModifier (c:rest) | c `elem` "#!" = [rest, c:rest]
+    dropModifier x        = [x]
+
+-- Get the variables from indices like ["x", "y"] in ${var[x+y+1]}
+prop_getIndexReferences1 = getIndexReferences "var[x+y+1]" == ["x", "y"]
+getIndexReferences s = fromMaybe [] $ do
+    index:_ <- matchRegex re s
+    return $ matchAllStrings variableNameRegex index
+  where
+    re = mkRegex "(\\[.*\\])"
+
+prop_getOffsetReferences1 = getOffsetReferences ":bar" == ["bar"]
+prop_getOffsetReferences2 = getOffsetReferences ":bar:baz" == ["bar", "baz"]
+prop_getOffsetReferences3 = getOffsetReferences "[foo]:bar" == ["bar"]
+prop_getOffsetReferences4 = getOffsetReferences "[foo]:bar:baz" == ["bar", "baz"]
+getOffsetReferences mods = fromMaybe [] $ do
+-- if mods start with [, then drop until ]
+    _:offsets:_ <- matchRegex re mods
+    return $ matchAllStrings variableNameRegex offsets
+  where
+    re = mkRegex "^(\\[.+\\])? *:([^-=?+].*)"
+
+
+-- Returns whether a token is a parameter expansion without any modifiers.
+-- True for $var ${var} $1 $#
+-- False for ${#var} ${var[x]} ${var:-0}
+isUnmodifiedParameterExpansion t =
+    case t of
+        T_DollarBraced _ False _ -> True
+        T_DollarBraced _ _ list ->
+            let str = concat $ oversimplify list
+            in getBracedReference str == str
+        _ -> False
+
+-- Return the referenced variable if (and only if) it's an unmodified parameter expansion.
+getUnmodifiedParameterExpansion t =
+    case t of
+        T_DollarBraced _ _ list -> do
+            let str = concat $ oversimplify list
+            guard $ getBracedReference str == str
+            return str
+        _ -> Nothing
+
+--- A list of the element and all its parents up to the root node.
+getPath tree = NE.unfoldr $ \t -> (t, Map.lookup (getId t) tree)
+
+isClosingFileOp op =
+    case op of
+        T_IoDuplicate _ (T_GREATAND _) "-" -> True
+        T_IoDuplicate _ (T_LESSAND  _) "-" -> True
+        _                                  -> False
+
+getEnableDirectives root =
+    case root of
+        T_Annotation _ list _ -> [s | EnableComment s <- list]
+        _ -> []
+
+getExtendedAnalysisDirective :: Token -> Maybe Bool
+getExtendedAnalysisDirective root =
+    case root of
+        T_Annotation _ list _ -> listToMaybe $ [s | ExtendedAnalysis s <- list]
+        _ -> Nothing
+
+return []
+runTests = $quickCheckAll

src/ShellCheck/Analyzer.hs

@@ -1,5 +1,5 @@
 {-
-    Copyright 2012-2019 Vidar Holen
+    Copyright 2012-2022 Vidar Holen
 
     This file is part of ShellCheck.
     https://www.shellcheck.net
@@ -25,6 +25,7 @@ import ShellCheck.Interface
 import Data.List
 import Data.Monoid
 import qualified ShellCheck.Checks.Commands
+import qualified ShellCheck.Checks.ControlFlow
 import qualified ShellCheck.Checks.Custom
 import qualified ShellCheck.Checks.ShellSupport
 
@@ -34,18 +35,21 @@ analyzeScript :: AnalysisSpec -> AnalysisResult
 analyzeScript spec = newAnalysisResult {
     arComments =
         filterByAnnotation spec params . nub $
-            runAnalytics spec
-            ++ runChecker params (checkers params)
+            runChecker params (checkers spec params)
 }
   where
     params = makeParameters spec
 
-checkers params = mconcat $ map ($ params) [
-    ShellCheck.Checks.Commands.checker,
+checkers spec params = mconcat $ map ($ params) [
+    ShellCheck.Analytics.checker spec,
+    ShellCheck.Checks.Commands.checker spec,
+    ShellCheck.Checks.ControlFlow.checker spec,
     ShellCheck.Checks.Custom.checker,
     ShellCheck.Checks.ShellSupport.checker
     ]
 
 optionalChecks = mconcat $ [
-    ShellCheck.Analytics.optionalChecks
+    ShellCheck.Analytics.optionalChecks,
+    ShellCheck.Checks.Commands.optionalChecks,
+    ShellCheck.Checks.ControlFlow.optionalChecks
     ]

src/ShellCheck/AnalyzerLib.hs

@@ -1,5 +1,5 @@
 {-
-    Copyright 2012-2019 Vidar Holen
+    Copyright 2012-2022 Vidar Holen
 
     This file is part of ShellCheck.
     https://www.shellcheck.net
@@ -23,13 +23,16 @@ module ShellCheck.AnalyzerLib where
 
 import ShellCheck.AST
 import ShellCheck.ASTLib
+import qualified ShellCheck.CFGAnalysis as CF
 import ShellCheck.Data
 import ShellCheck.Interface
 import ShellCheck.Parser
+import ShellCheck.Prelude
 import ShellCheck.Regex
 
 import Control.Arrow (first)
 import Control.DeepSeq
+import Control.Monad
 import Control.Monad.Identity
 import Control.Monad.RWS
 import Control.Monad.State
@@ -38,6 +41,7 @@ import Data.Char
 import Data.List
 import Data.Maybe
 import Data.Semigroup
+import qualified Data.List.NonEmpty as NE
 import qualified Data.Map as Map
 
 import Test.QuickCheck.All (forAllProperties)
@@ -79,10 +83,18 @@ composeAnalyzers f g x = f x >> g x
 data Parameters = Parameters {
     -- Whether this script has the 'lastpipe' option set/default.
     hasLastpipe        :: Bool,
+    -- Whether this script has the 'inherit_errexit' option set/default.
+    hasInheritErrexit  :: Bool,
     -- Whether this script has 'set -e' anywhere.
     hasSetE            :: Bool,
+    -- Whether this script has 'set -o pipefail' anywhere.
+    hasPipefail        :: Bool,
+    -- Whether this script has 'shopt -s execfail' anywhere.
+    hasExecfail        :: Bool,
     -- A linear (bad) analysis of data flow
     variableFlow       :: [StackData],
+    -- A map from Id to Token
+    idMap              :: Map.Map Id Token,
     -- A map from Id to parent Token
     parentMap          :: Map.Map Id Token,
     -- The shell type, such as Bash or Ksh
@@ -92,7 +104,9 @@ data Parameters = Parameters {
     -- The root node of the AST
     rootNode           :: Token,
     -- map from token id to start and end position
-    tokenPositions     :: Map.Map Id (Position, Position)
+    tokenPositions     :: Map.Map Id (Position, Position),
+    -- Result from Control Flow Graph analysis (including data flow analysis)
+    cfgAnalysis :: Maybe CF.CFGAnalysis
     } deriving (Show)
 
 -- TODO: Cache results of common AST ops here
@@ -142,7 +156,7 @@ producesComments c s = do
         prRoot pr
         let spec = defaultSpec pr
         let params = makeParameters spec
-        return . not . null $ runChecker params c
+        return . not . null $ filterByAnnotation spec params $ runChecker params c
 
 makeComment :: Severity -> Id -> Code -> String -> TokenComment
 makeComment severity id code note =
@@ -163,8 +177,12 @@ err   id code str = addComment $ makeComment ErrorC id code str
 info  id code str = addComment $ makeComment InfoC id code str
 style id code str = addComment $ makeComment StyleC id code str
 
+errWithFix :: MonadWriter [TokenComment] m => Id -> Code -> String -> Fix -> m ()
+errWithFix  = addCommentWithFix ErrorC
 warnWithFix :: MonadWriter [TokenComment] m => Id -> Code -> String -> Fix -> m ()
 warnWithFix  = addCommentWithFix WarningC
+infoWithFix :: MonadWriter [TokenComment] m => Id -> Code -> String -> Fix -> m ()
+infoWithFix = addCommentWithFix InfoC
 styleWithFix :: MonadWriter [TokenComment] m => Id -> Code -> String -> Fix -> m ()
 styleWithFix = addCommentWithFix StyleC
 
@@ -176,28 +194,58 @@ makeCommentWithFix :: Severity -> Id -> Code -> String -> Fix -> TokenComment
 makeCommentWithFix severity id code str fix =
     let comment = makeComment severity id code str
         withFix = comment {
-            tcFix = Just fix
+            -- If fix is empty, pretend it wasn't there.
+            tcFix = if null (fixReplacements fix) then Nothing else Just fix
         }
-    in withFix `deepseq` withFix
+    in force withFix
 
-makeParameters spec =
-    let params = Parameters {
+-- makeParameters :: CheckSpec -> Parameters
+makeParameters spec = params
+  where
+    extendedAnalysis = fromMaybe True $ msum [asExtendedAnalysis spec, getExtendedAnalysisDirective root]
+    params = Parameters {
         rootNode = root,
         shellType = fromMaybe (determineShell (asFallbackShell spec) root) $ asShellType spec,
         hasSetE = containsSetE root,
         hasLastpipe =
             case shellType params of
-                Bash -> containsLastpipe root
+                Bash -> isOptionSet "lastpipe" root
                 Dash -> False
+                BusyboxSh -> False
                 Sh   -> False
                 Ksh  -> True,
-
+        hasInheritErrexit =
+            case shellType params of
+                Bash -> isOptionSet "inherit_errexit" root
+                Dash -> True
+                BusyboxSh -> True
+                Sh   -> True
+                Ksh  -> False,
+        hasPipefail =
+            case shellType params of
+                Bash -> isOptionSet "pipefail" root
+                Dash -> True
+                BusyboxSh -> isOptionSet "pipefail" root
+                Sh   -> True
+                Ksh  -> isOptionSet "pipefail" root,
+        hasExecfail =
+            case shellType params of
+                Bash -> isOptionSet "execfail" root
+                _ -> False,
         shellTypeSpecified = isJust (asShellType spec) || isJust (asFallbackShell spec),
+        idMap = getTokenMap root,
         parentMap = getParentTree root,
         variableFlow = getVariableFlow params root,
-        tokenPositions = asTokenPositions spec
-    } in params
-  where root = asScript spec
+        tokenPositions = asTokenPositions spec,
+        cfgAnalysis = do
+            guard extendedAnalysis
+            return $ CF.analyzeControlFlow cfParams root
+    }
+    cfParams = CF.CFGParameters {
+        CF.cfLastpipe = hasLastpipe params,
+        CF.cfPipefail = hasPipefail params
+    }
+    root = asScript spec
 
 
 -- Does this script mention 'set -e' anywhere?
@@ -214,18 +262,30 @@ containsSetE root = isNothing $ doAnalysis (guard . not . isSetE) root
             _ -> False
     re = mkRegex "[[:space:]]-[^-]*e"
 
--- Does this script mention 'shopt -s lastpipe' anywhere?
--- Also used as a hack.
-containsLastpipe root =
+
+containsSetOption opt root = isNothing $ doAnalysis (guard . not . isPipefail) root
+  where
+    isPipefail t =
+        case t of
+            T_SimpleCommand {}  ->
+                t `isUnqualifiedCommand` "set" &&
+                    (opt `elem` oversimplify t ||
+                        "o" `elem` map snd (getAllFlags t))
+            _ -> False
+
+containsShopt shopt root =
         isNothing $ doAnalysis (guard . not . isShoptLastPipe) root
     where
         isShoptLastPipe t =
             case t of
                 T_SimpleCommand {}  ->
                     t `isUnqualifiedCommand` "shopt" &&
-                        ("lastpipe" `elem` oversimplify t)
+                        (shopt `elem` oversimplify t)
                 _ -> False
 
+-- Does this script mention 'shopt -s $opt' or 'set -o $opt' anywhere?
+isOptionSet opt root = containsShopt opt root || containsSetOption opt root
+
 
 prop_determineShell0 = determineShellTest "#!/bin/sh" == Sh
 prop_determineShell1 = determineShellTest "#!/usr/bin/env ksh" == Ksh
@@ -236,40 +296,28 @@ prop_determineShell5 = determineShellTest "#shellcheck shell=sh\nfoo" == Sh
 prop_determineShell6 = determineShellTest "#! /bin/sh" == Sh
 prop_determineShell7 = determineShellTest "#! /bin/ash" == Dash
 prop_determineShell8 = determineShellTest' (Just Ksh) "#!/bin/sh" == Sh
+prop_determineShell9 = determineShellTest "#!/bin/env -S dash -x" == Dash
+prop_determineShell10 = determineShellTest "#!/bin/env --split-string= dash -x" == Dash
+prop_determineShell11 = determineShellTest "#!/bin/busybox sh" == BusyboxSh -- busybox sh is a specific shell, not posix sh
+prop_determineShell12 = determineShellTest "#!/bin/busybox ash" == BusyboxSh
 
 determineShellTest = determineShellTest' Nothing
 determineShellTest' fallbackShell = determineShell fallbackShell . fromJust . prRoot . pScript
-determineShell fallbackShell t = fromMaybe Bash $ do
-    shellString <- foldl mplus Nothing $ getCandidates t
+determineShell fallbackShell t = fromMaybe Bash $
     shellForExecutable shellString `mplus` fallbackShell
   where
-    forAnnotation t =
-        case t of
-            (ShellOverride s) -> return s
-            _                 -> fail ""
-    getCandidates :: Token -> [Maybe String]
-    getCandidates t@T_Script {} = [Just $ fromShebang t]
-    getCandidates (T_Annotation _ annotations s) =
-        map forAnnotation annotations ++
-           [Just $ fromShebang s]
+    shellString = getCandidate t
+    getCandidate :: Token -> String
+    getCandidate t@T_Script {} = fromShebang t
+    getCandidate (T_Annotation _ annotations s) =
+        headOrDefault (fromShebang s) [s | ShellOverride s <- annotations]
     fromShebang (T_Script _ (T_Literal _ s) _) = executableFromShebang s
 
--- Given a string like "/bin/bash" or "/usr/bin/env dash",
--- return the shell basename like "bash" or "dash"
-executableFromShebang :: String -> String
-executableFromShebang = shellFor
-  where
-    shellFor s | "/env " `isInfixOf` s = head (drop 1 (words s)++[""])
-    shellFor s | ' ' `elem` s = shellFor $ takeWhile (/= ' ') s
-    shellFor s = reverse . takeWhile (/= '/') . reverse $ s
-
-
-
 -- Given a root node, make a map from Id to parent Token.
 -- This is used to populate parentMap in Parameters
 getParentTree :: Token -> Map.Map Id Token
 getParentTree t =
-    snd . snd $ runState (doStackAnalysis pre post t) ([], Map.empty)
+    snd $ execState (doStackAnalysis pre post t) ([], Map.empty)
   where
     pre t = modify (first ((:) t))
     post t = do
@@ -297,16 +345,16 @@ isStrictlyQuoteFree = isQuoteFreeNode True
 isQuoteFree = isQuoteFreeNode False
 
 
-isQuoteFreeNode strict tree t =
-    (isQuoteFreeElement t == Just True) ||
-        head (mapMaybe isQuoteFreeContext (drop 1 $ getPath tree t) ++ [False])
+isQuoteFreeNode strict shell tree t =
+    isQuoteFreeElement t ||
+        (fromMaybe False $ msum $ map isQuoteFreeContext $ NE.tail $ getPath tree t)
   where
     -- Is this node self-quoting in itself?
     isQuoteFreeElement t =
         case t of
-            T_Assignment {} -> return True
-            T_FdRedirect {} -> return True
-            _               -> Nothing
+            T_Assignment id _ _ _ _ -> assignmentIsQuoting id
+            T_FdRedirect {}         -> True
+            _                       -> False
 
     -- Are any subnodes inherently self-quoting?
     isQuoteFreeContext t =
@@ -316,7 +364,7 @@ isQuoteFreeNode strict tree t =
             TC_Binary _ DoubleBracket _ _ _ -> return True
             TA_Sequence {}                  -> return True
             T_Arithmetic {}                 -> return True
-            T_Assignment {}                 -> return True
+            T_Assignment id _ _ _ _         -> return $ assignmentIsQuoting id
             T_Redirecting {}                -> return False
             T_DoubleQuoted _ _              -> return True
             T_DollarDoubleQuoted _ _        -> return True
@@ -328,6 +376,18 @@ isQuoteFreeNode strict tree t =
             T_SelectIn {}                   -> return (not strict)
             _                               -> Nothing
 
+    -- Check whether this assignment is self-quoting due to being a recognized
+    -- assignment passed to a Declaration Utility. This will soon be required
+    -- by POSIX: https://austingroupbugs.net/view.php?id=351
+    assignmentIsQuoting id = shellParsesParamsAsAssignments || not (isAssignmentParamToCommand id)
+    shellParsesParamsAsAssignments = shell /= Sh
+
+    -- Is this assignment a parameter to a command like export/typeset/etc?
+    isAssignmentParamToCommand id =
+        case Map.lookup id tree of
+            Just (T_SimpleCommand _ _ (_:args)) -> id `elem` (map getId args)
+            _ -> False
+
 -- Check if a token is a parameter to a certain command by name:
 -- Example: isParamTo (parentMap params) "sed" t
 isParamTo :: Map.Map Id Token -> String -> Token -> Bool
@@ -349,7 +409,7 @@ isParamTo tree cmd =
 -- Get the parent command (T_Redirecting) of a Token, if any.
 getClosestCommand :: Map.Map Id Token -> Token -> Maybe Token
 getClosestCommand tree t =
-    findFirst findCommand $ getPath tree t
+    findFirst findCommand $ NE.toList $ getPath tree t
   where
     findCommand t =
         case t of
@@ -359,48 +419,43 @@ getClosestCommand tree t =
 
 -- Like above, if koala_man knew Haskell when starting this project.
 getClosestCommandM t = do
-    tree <- asks parentMap
-    return $ getClosestCommand tree t
+    params <- ask
+    return $ getClosestCommand (parentMap params) t
 
 -- Is the token used as a command name (the first word in a T_SimpleCommand)?
-usedAsCommandName tree token = go (getId token) (tail $ getPath tree token)
+usedAsCommandName tree token = go (getId token) (NE.tail $ getPath tree token)
   where
     go currentId (T_NormalWord id [word]:rest)
         | currentId == getId word = go id rest
     go currentId (T_DoubleQuoted id [word]:rest)
         | currentId == getId word = go id rest
-    go currentId (T_SimpleCommand _ _ (word:_):_)
-        | currentId == getId word = True
+    go currentId (t@(T_SimpleCommand _ _ (word:_)):_) =
+        getId word == currentId || getId (getCommandTokenOrThis t) == currentId
     go _ _ = False
 
--- A list of the element and all its parents up to the root node.
-getPath tree t = t :
-    case Map.lookup (getId t) tree of
-        Nothing     -> []
-        Just parent -> getPath tree parent
-
 -- Version of the above taking the map from the current context
 -- Todo: give this the name "getPath"
 getPathM t = do
-    map <- asks parentMap
-    return $ getPath map t
+    params <- ask
+    return $ getPath (parentMap params) t
 
 isParentOf tree parent child =
-    elem (getId parent) . map getId $ getPath tree child
+    any (\t -> parentId == getId t) (getPath tree child)
+  where
+    parentId = getId parent
 
 parents params = getPath (parentMap params)
 
 -- Find the first match in a list where the predicate is Just True.
 -- Stops if it's Just False and ignores Nothing.
 findFirst :: (a -> Maybe Bool) -> [a] -> Maybe a
-findFirst p l =
-    case l of
-        [] -> Nothing
-        (x:xs) ->
+findFirst p = foldr go Nothing
+  where
+    go x acc =
       case p x of
         Just True  -> return x
         Just False -> Nothing
-                Nothing    -> findFirst p xs
+        Nothing    -> acc
 
 -- Check whether a word is entirely output from a single command
 tokenIsJustCommandOutput t = case t of
@@ -415,8 +470,7 @@ tokenIsJustCommandOutput t = case t of
 
 -- TODO: Replace this with a proper Control Flow Graph
 getVariableFlow params t =
-    let (_, stack) = runState (doStackAnalysis startScope endScope t) []
-    in reverse stack
+    reverse $ execState (doStackAnalysis startScope endScope t) []
   where
     startScope t =
         let scopeType = leadType params t
@@ -454,7 +508,7 @@ leadType params t =
         T_BatsTest {} -> SubshellScope "@bats test"
         T_CoProcBody _ _  -> SubshellScope "coproc"
         T_Redirecting {}  ->
-            if fromMaybe False causesSubshell
+            if causesSubshell == Just True
             then SubshellScope "pipeline"
             else NoneScope
         _ -> NoneScope
@@ -467,91 +521,98 @@ leadType params t =
 
     causesSubshell = do
         (T_Pipeline _ _ list) <- parentPipeline
-        if length list <= 1
-            then return False
-            else if not $ hasLastpipe params
-                then return True
-                else return . not $ (getId . head $ reverse list) == getId t
+        return $ case list of
+            _:_:_ -> not (hasLastpipe params) || getId (last list) /= getId t
+            _ -> False
 
 getModifiedVariables t =
     case t of
         T_SimpleCommand _ vars [] ->
-            concatMap (\x -> case x of
-                                T_Assignment id _ name _ w  ->
-                                    [(x, x, name, dataTypeFrom DataString w)]
-                                _ -> []
-                      ) vars
-        c@T_SimpleCommand {} ->
-            getModifiedVariableCommand c
+            [(x, x, name, dataTypeFrom DataString w) | x@(T_Assignment id _ name _ w) <- vars]
+        T_SimpleCommand {} ->
+            getModifiedVariableCommand t
 
-        TA_Unary _ "++|" v@(TA_Variable _ name _)  ->
-            [(t, v, name, DataString $ SourceFrom [v])]
-        TA_Unary _ "|++" v@(TA_Variable _ name _)  ->
-            [(t, v, name, DataString $ SourceFrom [v])]
-        TA_Assignment _ op (TA_Variable _ name _) rhs -> maybeToList $ do
+        TA_Unary _ op v@(TA_Variable _ name _) | "--" `isInfixOf` op || "++" `isInfixOf` op ->
+            [(t, v, name, DataString SourceInteger)]
+        TA_Assignment _ op (TA_Variable _ name _) rhs -> do
             guard $ op `elem` ["=", "*=", "/=", "%=", "+=", "-=", "<<=", ">>=", "&=", "^=", "|="]
-            return (t, t, name, DataString $ SourceFrom [rhs])
+            return (t, t, name, DataString SourceInteger)
 
         T_BatsTest {} -> [
             (t, t, "lines", DataArray SourceExternal),
             (t, t, "status", DataString SourceInteger),
-            (t, t, "output", DataString SourceExternal)
+            (t, t, "output", DataString SourceExternal),
+            (t, t, "stderr", DataString SourceExternal),
+            (t, t, "stderr_lines", DataArray SourceExternal)
             ]
 
         -- Count [[ -v foo ]] as an "assignment".
         -- This is to prevent [ -v foo ] being unassigned or unused.
         TC_Unary id _ "-v" token -> maybeToList $ do
-            str <- fmap (takeWhile (/= '[')) $ -- Quoted index
-                    flip getLiteralStringExt token $ \x ->
-                case x of
-                    T_Glob _ s -> return s -- Unquoted index
-                    _          -> Nothing
-
-            guard . not . null $ str
+            str <- getVariableForTestDashV token
             return (t, token, str, DataString SourceChecked)
 
+        TC_Unary _ _ "-n" token -> markAsChecked t token
+        TC_Unary _ _ "-z" token -> markAsChecked t token
+        TC_Nullary _ _ token -> markAsChecked t token
+
         T_DollarBraced _ _ l -> maybeToList $ do
-            let string = bracedString t
+            let string = concat $ oversimplify l
             let modifier = getBracedModifier string
-            guard $ ":=" `isPrefixOf` modifier
+            guard $ any (`isPrefixOf` modifier) ["=", ":="]
             return (t, t, getBracedReference string, DataString $ SourceFrom [l])
 
-        t@(T_FdRedirect _ ('{':var) op) -> -- {foo}>&2 modifies foo
+        T_FdRedirect _ ('{':var) op -> -- {foo}>&2 modifies foo
             [(t, t, takeWhile (/= '}') var, DataString SourceInteger) | not $ isClosingFileOp op]
 
-        t@(T_CoProc _ name _) ->
-            [(t, t, fromMaybe "COPROC" name, DataArray SourceInteger)]
+        T_CoProc _ Nothing _ ->
+            [(t, t, "COPROC", DataArray SourceInteger)]
+
+        T_CoProc _ (Just token) _ -> do
+            name <- maybeToList $ getLiteralString token
+            [(t, t, name, DataArray SourceInteger)]
 
         --Points to 'for' rather than variable
         T_ForIn id str [] _ -> [(t, t, str, DataString SourceExternal)]
         T_ForIn id str words _ -> [(t, t, str, DataString $ SourceFrom words)]
         T_SelectIn id str words _ -> [(t, t, str, DataString $ SourceFrom words)]
         _ -> []
-
-isClosingFileOp op =
-    case op of
-        T_IoDuplicate _ (T_GREATAND _) "-" -> True
-        T_IoDuplicate _ (T_LESSAND  _) "-" -> True
-        _                                  -> False
+  where
+    markAsChecked place token = mapMaybe (f place) $ getWordParts token
+    f place t = case t of
+            T_DollarBraced _ _ l ->
+                let str = getBracedReference $ concat $ oversimplify l in do
+                    guard $ isVariableName str
+                    return (place, t, str, DataString SourceChecked)
+            _ -> Nothing
 
 
 -- Consider 'export/declare -x' a reference, since it makes the var available
 getReferencedVariableCommand base@(T_SimpleCommand _ _ (T_NormalWord _ (T_Literal _ x:_):rest)) =
     case x of
+        "declare" -> forDeclare
+        "typeset" -> forDeclare
+
         "export" -> if "f" `elem` flags
             then []
             else concatMap getReference rest
-        "declare" -> if
-                any (`elem` flags) ["x", "p"] &&
-                    (not $ any (`elem` flags) ["f", "F"])
+        "local" -> if "x" `elem` flags
             then concatMap getReference rest
             else []
         "trap" ->
             case rest of
-                head:_ -> map (\x -> (head, head, x)) $ getVariablesFromLiteralToken head
+                head:_ -> map (\x -> (base, head, x)) $ getVariablesFromLiteralToken head
                 _ -> []
+        "alias" -> [(base, token, name) | token <- rest, name <- getVariablesFromLiteralToken token]
         _ -> []
   where
+    forDeclare =
+            if
+                any (`elem` flags) ["x", "p"] &&
+                    (not $ any (`elem` flags) ["f", "F"])
+            then concatMap getReference rest
+            else []
+
     getReference t@(T_Assignment _ _ name _ value) = [(t, t, name)]
     getReference t@(T_NormalWord _ [T_Literal _ name]) | not ("-" `isPrefixOf` name) = [(t, t, name)]
     getReference _ = []
@@ -567,14 +628,20 @@ getReferencedVariableCommand _ = []
 --   VariableName :: String,   -- The variable name, i.e. foo
 --   VariableValue :: DataType -- A description of the value being assigned, i.e. "Literal string with value foo"
 -- )
-getModifiedVariableCommand base@(T_SimpleCommand _ _ (T_NormalWord _ (T_Literal _ x:_):rest)) =
+getModifiedVariableCommand base@(T_SimpleCommand id cmdPrefix (T_NormalWord _ (T_Literal _ x:_):rest)) =
    filter (\(_,_,s,_) -> not ("-" `isPrefixOf` s)) $
     case x of
+        "builtin" ->
+            getModifiedVariableCommand $ T_SimpleCommand id cmdPrefix rest
         "read" ->
-            let params = map getLiteral rest
-                readArrayVars = getReadArrayVariables rest
-            in
-                catMaybes . (++ readArrayVars) . takeWhile isJust . reverse $ params
+            let fallback = catMaybes $ takeWhile isJust (reverse $ map getLiteral rest)
+            in fromMaybe fallback $ do
+                parsed <- getGnuOpts flagsForRead rest
+                case lookup "a" parsed of
+                    Just (_, var) -> (:[]) <$> getLiteralArray var
+                    Nothing -> return $ catMaybes $
+                        map (getLiteral . snd . snd) $ filter (null . fst) parsed
+
         "getopts" ->
             case rest of
                 opts:var:_ -> maybeToList $ getLiteral var
@@ -585,8 +652,8 @@ getModifiedVariableCommand base@(T_SimpleCommand _ _ (T_NormalWord _ (T_Literal
         "export" ->
             if "f" `elem` flags then [] else concatMap getModifierParamString rest
 
-        "declare" -> if any (`elem` flags) ["F", "f", "p"] then [] else declaredVars
-        "typeset" -> declaredVars
+        "declare" -> forDeclare
+        "typeset" -> forDeclare
 
         "local" -> concatMap getModifierParamString rest
         "readonly" ->
@@ -598,6 +665,7 @@ getModifiedVariableCommand base@(T_SimpleCommand _ _ (T_NormalWord _ (T_Literal
             return (base, base, "@", DataString $ SourceFrom params)
 
         "printf" -> maybeToList $ getPrintfVariable rest
+        "wait" ->   maybeToList $ getWaitVariable rest
 
         "mapfile" -> maybeToList $ getMapfileArray base rest
         "readarray" -> maybeToList $ getMapfileArray base rest
@@ -610,14 +678,15 @@ getModifiedVariableCommand base@(T_SimpleCommand _ _ (T_NormalWord _ (T_Literal
         _ -> []
   where
     flags = map snd $ getAllFlags base
-    stripEquals s = let rest = dropWhile (/= '=') s in
-        if rest == "" then "" else tail rest
+    stripEquals s = drop 1 $ dropWhile (/= '=') s
     stripEqualsFrom (T_NormalWord id1 (T_Literal id2 s:rs)) =
         T_NormalWord id1 (T_Literal id2 (stripEquals s):rs)
     stripEqualsFrom (T_NormalWord id1 [T_DoubleQuoted id2 [T_Literal id3 s]]) =
         T_NormalWord id1 [T_DoubleQuoted id2 [T_Literal id3 (stripEquals s)]]
     stripEqualsFrom t = t
 
+    forDeclare = if any (`elem` flags) ["F", "f", "p"] then [] else declaredVars
+
     declaredVars = concatMap (getModifierParam defaultType) rest
       where
         defaultType = if any (`elem` flags) ["a", "A"] then DataArray else DataString
@@ -642,7 +711,7 @@ getModifiedVariableCommand base@(T_SimpleCommand _ _ (T_NormalWord _ (T_Literal
     getModifierParam _ _ = []
 
     letParamToLiteral token =
-          if var == ""
+          if null var
             then []
             else [(base, token, var, DataString $ SourceFrom [stripEqualsFrom token])]
         where var = takeWhile isVariableChar $ dropWhile (`elem` "+-") $ concat $ oversimplify token
@@ -656,36 +725,39 @@ getModifiedVariableCommand base@(T_SimpleCommand _ _ (T_NormalWord _ (T_Literal
                 _            -> return (t:fromMaybe [] (getSetParams rest))
     getSetParams [] = Nothing
 
-    getPrintfVariable list = f $ map (\x -> (x, getLiteralString x)) list
-      where
-        f ((_, Just "-v") : (t, Just var) : _) = return (base, t, varName, varType $ SourceFrom list)
-            where
-                (varName, varType) = case elemIndex '[' var of
-                    Just i -> (take i var, DataArray)
-                    Nothing -> (var, DataString)
-        f (_:rest) = f rest
-        f [] = fail "not found"
+    getPrintfVariable list = getFlagAssignedVariable "v" (SourceFrom list) $ getBsdOpts "v:" list
+    getWaitVariable   list = getFlagAssignedVariable "p" SourceInteger     $ return $ getGenericOpts list
+
+    getFlagAssignedVariable str dataSource maybeFlags = do
+        flags <- maybeFlags
+        (_, (flag, value)) <- find ((== str) . fst) flags
+        variableName <- getLiteralStringExt (const $ return "!") value
+        let (baseName, index) = span (/= '[') variableName
+        return (base, value, baseName, (if null index then DataString else DataArray) dataSource)
 
     -- mapfile has some curious syntax allowing flags plus 0..n variable names
-    -- where only the first non-option one is used if any. Here we cheat and
-    -- just get the last one, if it's a variable name.
-    getMapfileArray base arguments = do
-        lastArg <- listToMaybe (reverse arguments)
-        name <- getLiteralString lastArg
+    -- where only the first non-option one is used if any.
+    getMapfileArray base rest = parseArgs `mplus` fallback
+      where
+        parseArgs :: Maybe (Token, Token, String, DataType)
+        parseArgs = do
+            args <- getGnuOpts "d:n:O:s:u:C:c:t" rest
+            case [y | ("",(_,y)) <- args] of
+                [] ->
+                    return (base, base, "MAPFILE", DataArray SourceExternal)
+                first:_ -> do
+                    name <- getLiteralString first
                     guard $ isVariableName name
-        return (base, lastArg, name, DataArray SourceExternal)
-
-    -- get all the array variables used in read, e.g. read -a arr
-    getReadArrayVariables args =
-        map (getLiteralArray . snd)
-            (filter (isArrayFlag . fst) (zip args (tail args)))
-
-    isArrayFlag x = fromMaybe False $ do
-        str <- getLiteralString x
-        return $ case str of
-                    '-':'-':_ -> False
-                    '-':str -> 'a' `elem` str
-                    _ -> False
+                    return (base, first, name, DataArray SourceExternal)
+        -- If arg parsing fails (due to bad or new flags), get the last variable name
+        fallback :: Maybe (Token, Token, String, DataType)
+        fallback = do
+            (name, token) <- listToMaybe . mapMaybe f $ reverse rest
+            return (base, token, name, DataArray SourceExternal)
+        f arg = do
+            name <- getLiteralString arg
+            guard $ isVariableName name
+            return (name, arg)
 
     -- get the FLAGS_ variable created by a shflags DEFINE_ call
     getFlagVariable (n:v:_) = do
@@ -695,28 +767,23 @@ getModifiedVariableCommand base@(T_SimpleCommand _ _ (T_NormalWord _ (T_Literal
 
 getModifiedVariableCommand _ = []
 
-getIndexReferences s = fromMaybe [] $ do
-    match <- matchRegex re s
-    index <- match !!! 0
-    return $ matchAllStrings variableNameRegex index
+-- Given a NormalWord like foo or foo[$bar], get foo.
+-- Primarily used to get references for [[ -v foo[bar] ]]
+getVariableForTestDashV :: Token -> Maybe String
+getVariableForTestDashV t = do
+    str <- takeWhile ('[' /=) <$> getLiteralStringExt toStr t
+    guard $ isVariableName str
+    return str
   where
-    re = mkRegex "(\\[.*\\])"
-
-prop_getOffsetReferences1 = getOffsetReferences ":bar" == ["bar"]
-prop_getOffsetReferences2 = getOffsetReferences ":bar:baz" == ["bar", "baz"]
-prop_getOffsetReferences3 = getOffsetReferences "[foo]:bar" == ["bar"]
-prop_getOffsetReferences4 = getOffsetReferences "[foo]:bar:baz" == ["bar", "baz"]
-getOffsetReferences mods = fromMaybe [] $ do
--- if mods start with [, then drop until ]
-    match <- matchRegex re mods
-    offsets <- match !!! 1
-    return $ matchAllStrings variableNameRegex offsets
-  where
-    re = mkRegex "^(\\[.+\\])? *:([^-=?+].*)"
+    -- foo[bar] gets parsed with [bar] as a glob, so undo that
+    toStr (T_Glob _ s) = return s
+    -- Turn foo[$x] into foo[\0] so that we can get the constant array name
+    -- in a non-constant expression (while filtering out foo$x[$y])
+    toStr _ = return "\0"
 
 getReferencedVariables parents t =
     case t of
-        T_DollarBraced id _ l -> let str = bracedString t in
+        T_DollarBraced id _ l -> let str = concat $ oversimplify l in
             (t, t, getBracedReference str) :
                 map (\x -> (l, l, x)) (
                     getIndexReferences str
@@ -731,7 +798,7 @@ getReferencedVariables parents t =
         TC_Unary id _ "-v" token -> getIfReference t token
         TC_Unary id _ "-R" token -> getIfReference t token
         TC_Binary id DoubleBracket op lhs rhs ->
-            if isDereferencing op
+            if isDereferencingBinaryOp op
             then concatMap (getIfReference t) [lhs, rhs]
             else []
 
@@ -741,7 +808,7 @@ getReferencedVariables parents t =
             (t, t, "output")
             ]
 
-        t@(T_FdRedirect _ ('{':var) op) -> -- {foo}>&- references and closes foo
+        T_FdRedirect _ ('{':var) op -> -- {foo}>&- references and closes foo
             [(t, t, takeWhile (/= '}') var) | isClosingFileOp op]
         x -> getReferencedVariableCommand x
   where
@@ -758,20 +825,18 @@ getReferencedVariables parents t =
 
     literalizer t = case t of
         T_Glob _ s -> return s    -- Also when parsed as globs
-        _          -> Nothing
+        _          -> []
 
     getIfReference context token = maybeToList $ do
-            str <- getLiteralStringExt literalizer token
-            guard . not $ null str
-            when (isDigit $ head str) $ fail "is a number"
+            str <- getVariableForTestDashV token
             return (context, token, getBracedReference str)
 
-    isDereferencing = (`elem` ["-eq", "-ne", "-lt", "-le", "-gt", "-ge"])
-
     isArithmeticAssignment t = case getPath parents t of
-        this: TA_Assignment _ "=" lhs _ :_ -> lhs == t
+        this NE.:| TA_Assignment _ "=" lhs _ :_ -> lhs == t
         _                                  -> False
 
+isDereferencingBinaryOp = (`elem` ["-eq", "-ne", "-lt", "-le", "-gt", "-ge"])
+
 dataTypeFrom defaultType v = (case v of T_Array {} -> DataArray; _ -> defaultType) $ SourceFrom [v]
 
 
@@ -783,8 +848,8 @@ isCommand token str = isCommandMatch token (\cmd -> cmd  == str || ('/' : str) `
 -- Compare a command to a literal. Like above, but checks full path.
 isUnqualifiedCommand token str = isCommandMatch token (== str)
 
-isCommandMatch token matcher = fromMaybe False $
-    fmap matcher (getCommandName token)
+isCommandMatch token matcher = maybe False
+    matcher (getCommandName token)
 
 -- Does this regex look like it was intended as a glob?
 -- True:  *foo*
@@ -794,104 +859,23 @@ isConfusedGlobRegex ('*':_) = True
 isConfusedGlobRegex [x,'*'] | x `notElem` "\\." = True
 isConfusedGlobRegex _       = False
 
-isVariableStartChar x = x == '_' || isAsciiLower x || isAsciiUpper x
-isVariableChar x = isVariableStartChar x || isDigit x
-variableNameRegex = mkRegex "[_a-zA-Z][_a-zA-Z0-9]*"
-
-prop_isVariableName1 = isVariableName "_fo123"
-prop_isVariableName2 = not $ isVariableName "4"
-prop_isVariableName3 = not $ isVariableName "test: "
-isVariableName (x:r) = isVariableStartChar x && all isVariableChar r
-isVariableName _     = False
-
 getVariablesFromLiteralToken token =
-    getVariablesFromLiteral (fromJust $ getLiteralStringExt (const $ return " ") token)
+    getVariablesFromLiteral (getLiteralStringDef " " token)
 
 -- Try to get referenced variables from a literal string like "$foo"
 -- Ignores tons of cases like arithmetic evaluation and array indices.
 prop_getVariablesFromLiteral1 =
     getVariablesFromLiteral "$foo${bar//a/b}$BAZ" == ["foo", "bar", "BAZ"]
 getVariablesFromLiteral string =
-    map (!! 0) $ matchAllSubgroups variableRegex string
+    map head $ matchAllSubgroups variableRegex string
   where
     variableRegex = mkRegex "\\$\\{?([A-Za-z0-9_]+)"
 
--- Get the variable name from an expansion like ${var:-foo}
-prop_getBracedReference1 = getBracedReference "foo" == "foo"
-prop_getBracedReference2 = getBracedReference "#foo" == "foo"
-prop_getBracedReference3 = getBracedReference "#" == "#"
-prop_getBracedReference4 = getBracedReference "##" == "#"
-prop_getBracedReference5 = getBracedReference "#!" == "!"
-prop_getBracedReference6 = getBracedReference "!#" == "#"
-prop_getBracedReference7 = getBracedReference "!foo#?" == "foo"
-prop_getBracedReference8 = getBracedReference "foo-bar" == "foo"
-prop_getBracedReference9 = getBracedReference "foo:-bar" == "foo"
-prop_getBracedReference10= getBracedReference "foo: -1" == "foo"
-prop_getBracedReference11= getBracedReference "!os*" == ""
-prop_getBracedReference12= getBracedReference "!os?bar**" == ""
-prop_getBracedReference13= getBracedReference "foo[bar]" == "foo"
-getBracedReference s = fromMaybe s $
-    nameExpansion s `mplus` takeName noPrefix `mplus` getSpecial noPrefix `mplus` getSpecial s
-  where
-    noPrefix = dropPrefix s
-    dropPrefix (c:rest) = if c `elem` "!#" then rest else c:rest
-    dropPrefix ""       = ""
-    takeName s = do
-        let name = takeWhile isVariableChar s
-        guard . not $ null name
-        return name
-    getSpecial (c:_) =
-        if c `elem` "*@#?-$!" then return [c] else fail "not special"
-    getSpecial _ = fail "empty"
-
-    nameExpansion ('!':rest) = do -- e.g. ${!foo*bar*}
-        let suffix = dropWhile isVariableChar rest
-        guard $ suffix /= rest -- e.g. ${!@}
-        first <- suffix !!! 0
-        guard $ first `elem` "*?"
-        return ""
-    nameExpansion _ = Nothing
-
-prop_getBracedModifier1 = getBracedModifier "foo:bar:baz" == ":bar:baz"
-prop_getBracedModifier2 = getBracedModifier "!var:-foo" == ":-foo"
-prop_getBracedModifier3 = getBracedModifier "foo[bar]" == "[bar]"
-getBracedModifier s = fromMaybe "" . listToMaybe $ do
-    let var = getBracedReference s
-    a <- dropModifier s
-    dropPrefix var a
-  where
-    dropPrefix [] t        = return t
-    dropPrefix (a:b) (c:d) | a == c = dropPrefix b d
-    dropPrefix _ _         = []
-
-    dropModifier (c:rest) | c `elem` "#!" = [rest, c:rest]
-    dropModifier x        = [x]
-
--- Useful generic functions.
-
--- Run an action in a Maybe (or do nothing).
--- Example:
--- potentially $ do
---   s <- getLiteralString cmd
---   guard $ s `elem` ["--recursive", "-r"]
---   return $ warn .. "Something something recursive"
-potentially :: Monad m => Maybe (m ()) -> m ()
-potentially = fromMaybe (return ())
-
--- Get element 0 or a default. Like `head` but safe.
-headOrDefault _ (a:_) = a
-headOrDefault def _   = def
-
---- Get element n of a list, or Nothing. Like `!!` but safe.
-(!!!) list i =
-    case drop i list of
-        []    -> Nothing
-        (r:_) -> Just r
 
 -- Run a command if the shell is in the given list
 whenShell l c = do
-    shell <- asks shellType
-    when (shell `elem` l ) c
+    params <- ask
+    when (shellType params `elem` l ) c
 
 
 filterByAnnotation asSpec params =
@@ -920,55 +904,41 @@ isCountingReference _ = False
 -- FIXME: doesn't handle ${a:+$var} vs ${a:+"$var"}
 isQuotedAlternativeReference t =
     case t of
-        T_DollarBraced _ _ _ ->
-            getBracedModifier (bracedString t) `matches` re
+        T_DollarBraced _ _ l ->
+            getBracedModifier (concat $ oversimplify l) `matches` re
         _ -> False
   where
     re = mkRegex "(^|\\]):?\\+"
 
--- getGnuOpts "erd:u:" will parse a SimpleCommand like
---     read -re -d : -u 3 bar
--- into
---     Just [("r", -re), ("e", -re), ("d", :), ("u", 3), ("", bar)]
--- where flags with arguments map to arguments, while others map to themselves.
--- Any unrecognized flag will result in Nothing.
-getGnuOpts = getOpts getAllFlags
-getBsdOpts = getOpts getLeadingFlags
-getOpts :: (Token -> [(Token, String)]) -> String -> Token -> Maybe [(String, Token)]
-getOpts flagTokenizer string cmd = process flags
+supportsArrays Bash = True
+supportsArrays Ksh = True
+supportsArrays _ = False
+
+isTrueAssignmentSource c =
+    case c of
+        DataString SourceChecked -> False
+        DataString SourceDeclaration -> False
+        DataArray SourceChecked -> False
+        DataArray SourceDeclaration -> False
+        _ -> True
+
+modifiesVariable params token name =
+    or $ map check flow
   where
-    flags = flagTokenizer cmd
-    flagList (c:':':rest) = ([c], True) : flagList rest
-    flagList (c:rest)     = ([c], False) : flagList rest
-    flagList []           = []
-    flagMap = Map.fromList $ ("", False) : flagList string
+    flow = getVariableFlow params token
+    check t =
+        case t of
+            Assignment (_, _, n, source) -> isTrueAssignmentSource source && n == name
+            _ -> False
 
-    process [] = return []
-    process [(token, flag)] = do
-        takesArg <- Map.lookup flag flagMap
-        guard $ not takesArg
-        return [(flag, token)]
-    process ((token1, flag1):rest2@((token2, flag2):rest)) = do
-        takesArg <- Map.lookup flag1 flagMap
-        if takesArg
-            then do
-                guard $ flag2 == ""
-                more <- process rest
-                return $ (flag1, token2) : more
-            else do
-                more <- process rest2
-                return $ (flag1, token1) : more
-
-supportsArrays shell = shell == Bash || shell == Ksh
-
--- Returns true if the shell is Bash or Ksh (sorry for the name, Ksh)
-isBashLike :: Parameters -> Bool
-isBashLike params =
-    case shellType params of
-        Bash -> True
-        Ksh -> True
-        Dash -> False
-        Sh -> False
+isTestCommand t =
+    case t of
+        T_Condition {} -> True
+        T_SimpleCommand {} -> t `isCommand` "test"
+        T_Redirecting _ _ t -> isTestCommand t
+        T_Annotation _ _ t -> isTestCommand t
+        T_Pipeline _ _ [t] -> isTestCommand t
+        _ -> False
 
 return []
 runTests =  $( [| $(forAllProperties) (quickCheckWithResult (stdArgs { maxSuccess = 1 }) ) |])

src/ShellCheck/Checker.hs

@@ -1,5 +1,5 @@
 {-
-    Copyright 2012-2019 Vidar Holen
+    Copyright 2012-2022 Vidar Holen
 
     This file is part of ShellCheck.
     https://www.shellcheck.net
@@ -20,10 +20,12 @@
 {-# LANGUAGE TemplateHaskell #-}
 module ShellCheck.Checker (checkScript, ShellCheck.Checker.runTests) where
 
+import ShellCheck.Analyzer
+import ShellCheck.ASTLib
 import ShellCheck.Interface
 import ShellCheck.Parser
-import ShellCheck.Analyzer
 
+import Debug.Trace -- DO NOT SUBMIT
 import Data.Either
 import Data.Functor
 import Data.List
@@ -48,7 +50,7 @@ tokenToPosition startMap t = fromMaybe fail $ do
   where
     fail = error "Internal shellcheck error: id doesn't exist. Please report!"
 
-shellFromFilename filename = foldl mplus Nothing candidates
+shellFromFilename filename = listToMaybe candidates
   where
     shellExtensions = [(".ksh", Ksh)
                       ,(".bash", Bash)
@@ -57,7 +59,7 @@ shellFromFilename filename = foldl mplus Nothing candidates
                       -- The `.sh` is too generic to determine the shell:
                       -- We fallback to Bash in this case and emit SC2148 if there is no shebang
     candidates =
-        map (\(ext,sh) -> if ext `isSuffixOf` filename then Just sh else Nothing) shellExtensions
+        [sh | (ext,sh) <- shellExtensions, ext `isSuffixOf` filename]
 
 checkScript :: Monad m => SystemInterface m -> CheckSpec -> m CheckResult
 checkScript sys spec = do
@@ -85,12 +87,13 @@ checkScript sys spec = do
                     asCheckSourced = csCheckSourced spec,
                     asExecutionMode = Executed,
                     asTokenPositions = tokenPositions,
-                    asOptionalChecks = csOptionalChecks spec
+                    asExtendedAnalysis = csExtendedAnalysis spec,
+                    asOptionalChecks = getEnableDirectives root ++ csOptionalChecks spec
                 } where as = newAnalysisSpec root
         let analysisMessages =
-                fromMaybe [] $
+                maybe []
                     (arComments . analyzeScript . analysisSpec)
-                        <$> prRoot result
+                        $ prRoot result
         let translator = tokenToPosition tokenPositions
         return . nub . sortMessages . filter shouldInclude $
             (parseMessages ++ map translator analysisMessages)
@@ -104,7 +107,7 @@ checkScript sys spec = do
             code     = cCode (pcComment pc)
             severity = cSeverity (pcComment pc)
 
-    sortMessages = sortBy (comparing order)
+    sortMessages = sortOn order
     order pc =
         let pos = pcStartPos pc
             comment = pcComment pc in
@@ -156,6 +159,11 @@ checkWithIncludesAndSourcePath includes mapper = getErrors
         siFindSource = mapper
     }
 
+checkWithRcIncludesAndSourcePath rc includes mapper = getErrors
+    (mockRcFile rc $ mockedSystemInterface includes) {
+        siFindSource = mapper
+    }
+
 prop_findsParseIssue = check "echo \"$12\"" == [1037]
 
 prop_commentDisablesParseIssue1 =
@@ -198,11 +206,11 @@ prop_optionDisablesBadShebang =
                 }
 
 prop_annotationDisablesBadShebang =
-    [] == check "#!/usr/bin/python\n# shellcheck shell=sh\ntrue\n"
+    null $ check "#!/usr/bin/python\n# shellcheck shell=sh\ntrue\n"
 
 
 prop_canParseDevNull =
-    [] == check "source /dev/null"
+    null $ check "source /dev/null"
 
 prop_failsWhenNotSourcing =
     [1091, 2154] == check "source lol; echo \"$bar\""
@@ -218,7 +226,7 @@ prop_worksWhenDotting =
 
 -- FIXME: This should really be giving [1093], "recursively sourced"
 prop_noInfiniteSourcing =
-    [] == checkWithIncludes  [("lib", "source lib")] "source lib"
+    null $ checkWithIncludes  [("lib", "source lib")] "source lib"
 
 prop_canSourceBadSyntax =
     [1094, 2086] == checkWithIncludes [("lib", "for f; do")] "source lib; echo $1"
@@ -229,9 +237,18 @@ prop_cantSourceDynamic =
 prop_cantSourceDynamic2 =
     [1090] == checkWithIncludes [("lib", "")] "source ~/foo"
 
+prop_canStripPrefixAndSource =
+    null $ checkWithIncludes [("./lib", "")] "source \"$MYDIR/lib\""
+
+prop_canStripPrefixAndSource2 =
+    null $ checkWithIncludes [("./utils.sh", "")] "source \"$(dirname \"${BASH_SOURCE[0]}\")/utils.sh\""
+
 prop_canSourceDynamicWhenRedirected =
     null $ checkWithIncludes [("lib", "")] "#shellcheck source=lib\n. \"$1\""
 
+prop_canRedirectWithSpaces =
+    null $ checkWithIncludes [("my file", "")] "#shellcheck source=\"my file\"\n. \"$1\""
+
 prop_recursiveAnalysis =
     [2086] == checkRecursive [("lib", "echo $1")] "source lib"
 
@@ -239,10 +256,10 @@ prop_recursiveParsing =
     [1037] == checkRecursive [("lib", "echo \"$10\"")] "source lib"
 
 prop_nonRecursiveAnalysis =
-    [] == checkWithIncludes [("lib", "echo $1")] "source lib"
+    null $ checkWithIncludes [("lib", "echo $1")] "source lib"
 
 prop_nonRecursiveParsing =
-    [] == checkWithIncludes [("lib", "echo \"$10\"")] "source lib"
+    null $ checkWithIncludes [("lib", "echo \"$10\"")] "source lib"
 
 prop_sourceDirectiveDoesntFollowFile =
     null $ checkWithIncludes
@@ -270,7 +287,7 @@ prop_filewideAnnotation8 = null $
     check "# Disable $? warning\n#shellcheck disable=SC2181\n# Disable quoting warning\n#shellcheck disable=2086\ntrue\n[ $? == 0 ] && echo $1"
 
 prop_sourcePartOfOriginalScript = -- #1181: -x disabled posix warning for 'source'
-    2039 `elem` checkWithIncludes [("./saywhat.sh", "echo foo")] "#!/bin/sh\nsource ./saywhat.sh"
+    3046 `elem` checkWithIncludes [("./saywhat.sh", "echo foo")] "#!/bin/sh\nsource ./saywhat.sh"
 
 prop_spinBug1413 = null $ check "fun() {\n# shellcheck disable=SC2188\n> /dev/null\n}\n"
 
@@ -288,6 +305,27 @@ prop_deducesTypeFromExtension2 = result == [2079]
         csScript = "(( 3.14 ))"
     }
 
+prop_canDisableShebangWarning = null $ result
+  where
+    result = checkWithSpec [] emptyCheckSpec {
+        csFilename = "file.sh",
+        csScript = "#shellcheck disable=SC2148\nfoo"
+    }
+
+prop_canDisableAllWarnings = result == [2086]
+  where
+    result = checkWithSpec [] emptyCheckSpec {
+        csFilename = "file.sh",
+        csScript = "#!/bin/sh\necho $1\n#shellcheck disable=all\necho `echo $1`"
+    }
+
+prop_canDisableParseErrors = null $ result
+  where
+    result = checkWithSpec [] emptyCheckSpec {
+        csFilename = "file.sh",
+        csScript = "#shellcheck disable=SC1073,SC1072,SC2148\n()"
+    }
+
 prop_shExtensionDoesntMatter = result == [2148]
   where
     result = checkWithSpec [] emptyCheckSpec {
@@ -328,7 +366,7 @@ prop_optionIncludes4 =
     [2154] == checkOptionIncludes (Just [2154]) "#!/bin/sh\n var='a b'\n echo $var\n echo $bar"
 
 
-prop_readsRcFile = result == []
+prop_readsRcFile = null result
   where
     result = checkWithRc "disable=2086" emptyCheckSpec {
         csScript = "#!/bin/sh\necho $1",
@@ -364,7 +402,7 @@ prop_canEnableOptionalsWithRc = result == [2244]
 
 prop_sourcePathRedirectsName = result == [2086]
   where
-    f "dir/myscript" _ "lib" = return "foo/lib"
+    f "dir/myscript" _ _ "lib" = return "foo/lib"
     result = checkWithIncludesAndSourcePath [("foo/lib", "echo $1")] f emptyCheckSpec {
         csScript = "#!/bin/bash\nsource lib",
         csFilename = "dir/myscript",
@@ -373,22 +411,154 @@ prop_sourcePathRedirectsName = result == [2086]
 
 prop_sourcePathAddsAnnotation = result == [2086]
   where
-    f "dir/myscript" ["mypath"] "lib" = return "foo/lib"
+    f "dir/myscript" _ ["mypath"] "lib" = return "foo/lib"
     result = checkWithIncludesAndSourcePath [("foo/lib", "echo $1")] f emptyCheckSpec {
         csScript = "#!/bin/bash\n# shellcheck source-path=mypath\nsource lib",
         csFilename = "dir/myscript",
         csCheckSourced = True
     }
 
+prop_sourcePathWorksWithSpaces = result == [2086]
+  where
+    f "dir/myscript" _ ["my path"] "lib" = return "foo/lib"
+    result = checkWithIncludesAndSourcePath [("foo/lib", "echo $1")] f emptyCheckSpec {
+        csScript = "#!/bin/bash\n# shellcheck source-path='my path'\nsource lib",
+        csFilename = "dir/myscript",
+        csCheckSourced = True
+    }
+
 prop_sourcePathRedirectsDirective = result == [2086]
   where
-    f "dir/myscript" _ "lib" = return "foo/lib"
-    f _ _ _ = return "/dev/null"
+    f "dir/myscript" _ _ "lib" = return "foo/lib"
+    f _ _ _ _ = return "/dev/null"
     result = checkWithIncludesAndSourcePath [("foo/lib", "echo $1")] f emptyCheckSpec {
         csScript = "#!/bin/bash\n# shellcheck source=lib\nsource kittens",
         csFilename = "dir/myscript",
         csCheckSourced = True
     }
 
+prop_rcCanAllowExternalSources = result == [2086]
+  where
+    f "dir/myscript" (Just True) _ "mylib" = return "resolved/mylib"
+    f a b c d = error $ show ("Unexpected", a, b, c, d)
+    result = checkWithRcIncludesAndSourcePath "external-sources=true" [("resolved/mylib", "echo $1")] f emptyCheckSpec {
+        csScript = "#!/bin/bash\nsource mylib",
+        csFilename = "dir/myscript",
+        csCheckSourced = True
+    }
+
+prop_rcCanDenyExternalSources = result == [2086]
+  where
+    f "dir/myscript" (Just False) _ "mylib" = return "resolved/mylib"
+    f a b c d = error $ show ("Unexpected", a, b, c, d)
+    result = checkWithRcIncludesAndSourcePath "external-sources=false" [("resolved/mylib", "echo $1")] f emptyCheckSpec {
+        csScript = "#!/bin/bash\nsource mylib",
+        csFilename = "dir/myscript",
+        csCheckSourced = True
+    }
+
+prop_rcCanLeaveExternalSourcesUnspecified = result == [2086]
+  where
+    f "dir/myscript" Nothing _ "mylib" = return "resolved/mylib"
+    f a b c d = error $ show ("Unexpected", a, b, c, d)
+    result = checkWithRcIncludesAndSourcePath "" [("resolved/mylib", "echo $1")] f emptyCheckSpec {
+        csScript = "#!/bin/bash\nsource mylib",
+        csFilename = "dir/myscript",
+        csCheckSourced = True
+    }
+
+prop_fileCanDisableExternalSources = result == [2006, 2086]
+  where
+    f "dir/myscript" (Just True) _ "withExternal" = return "withExternal"
+    f "dir/myscript" (Just False) _ "withoutExternal" = return "withoutExternal"
+    f a b c d = error $ show ("Unexpected", a, b, c, d)
+    result = checkWithRcIncludesAndSourcePath "external-sources=true" [("withExternal", "echo $1"), ("withoutExternal", "_=`foo`")] f emptyCheckSpec {
+        csScript = "#!/bin/bash\ntrue\nsource withExternal\n# shellcheck external-sources=false\nsource withoutExternal",
+        csFilename = "dir/myscript",
+        csCheckSourced = True
+    }
+
+prop_fileCannotEnableExternalSources = result == [1144]
+  where
+    f "dir/myscript" Nothing _ "foo" = return "foo"
+    f a b c d = error $ show ("Unexpected", a, b, c, d)
+    result = checkWithRcIncludesAndSourcePath "" [("foo", "true")] f emptyCheckSpec {
+        csScript = "#!/bin/bash\n# shellcheck external-sources=true\nsource foo",
+        csFilename = "dir/myscript",
+        csCheckSourced = True
+    }
+
+prop_fileCannotEnableExternalSources2 = result == [1144]
+  where
+    f "dir/myscript" (Just False) _ "foo" = return "foo"
+    f a b c d = error $ show ("Unexpected", a, b, c, d)
+    result = checkWithRcIncludesAndSourcePath "external-sources=false" [("foo", "true")] f emptyCheckSpec {
+        csScript = "#!/bin/bash\n# shellcheck external-sources=true\nsource foo",
+        csFilename = "dir/myscript",
+        csCheckSourced = True
+    }
+
+prop_rcCanSuppressEarlyProblems1 = null result
+  where
+    result = checkWithRc "disable=1071" emptyCheckSpec {
+        csScript = "#!/bin/zsh\necho $1"
+    }
+
+prop_rcCanSuppressEarlyProblems2 = null result
+  where
+    result = checkWithRc "disable=1104" emptyCheckSpec {
+        csScript = "!/bin/bash\necho 'hello world'"
+    }
+
+prop_sourceWithHereDocWorks = null result
+  where
+    result = checkWithIncludes [("bar", "true\n")] "source bar << eof\nlol\neof"
+
+prop_hereDocsAreParsedWithoutTrailingLinefeed = 1044 `elem` result
+  where
+    result = check "cat << eof"
+
+prop_hereDocsWillHaveParsedIndices = null result
+  where
+    result = check "#!/bin/bash\nmy_array=(a b)\ncat <<EOF >> ./test\n $(( 1 + my_array[1] ))\nEOF"
+
+prop_rcCanSuppressDfa = null result
+  where
+    result = checkWithRc "extended-analysis=false" emptyCheckSpec {
+        csScript = "#!/bin/sh\nexit; foo;"
+    }
+
+prop_fileCanSuppressDfa = null $ traceShowId result
+  where
+    result = checkWithRc "" emptyCheckSpec {
+        csScript = "#!/bin/sh\n# shellcheck extended-analysis=false\nexit; foo;"
+    }
+
+prop_fileWinsWhenSuppressingDfa1 = null result
+  where
+    result = checkWithRc "extended-analysis=true" emptyCheckSpec {
+        csScript = "#!/bin/sh\n# shellcheck extended-analysis=false\nexit; foo;"
+    }
+
+prop_fileWinsWhenSuppressingDfa2 = result == [2317]
+  where
+    result = checkWithRc "extended-analysis=false" emptyCheckSpec {
+        csScript = "#!/bin/sh\n# shellcheck extended-analysis=true\nexit; foo;"
+    }
+
+prop_flagWinsWhenSuppressingDfa1 = result == [2317]
+  where
+    result = checkWithRc "extended-analysis=false" emptyCheckSpec {
+        csScript = "#!/bin/sh\n# shellcheck extended-analysis=false\nexit; foo;",
+        csExtendedAnalysis = Just True
+    }
+
+prop_flagWinsWhenSuppressingDfa2 = null result
+  where
+    result = checkWithRc "extended-analysis=true" emptyCheckSpec {
+        csScript = "#!/bin/sh\n# shellcheck extended-analysis=true\nexit; foo;",
+        csExtendedAnalysis = Just False
+    }
+
 return []
 runTests = $quickCheckAll

src/ShellCheck/Checks/ControlFlow.hs

@@ -0,0 +1,101 @@
+{-
+    Copyright 2022 Vidar Holen
+
+    This file is part of ShellCheck.
+    https://www.shellcheck.net
+
+    ShellCheck is free software: you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    ShellCheck is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with this program.  If not, see <https://www.gnu.org/licenses/>.
+-}
+{-# LANGUAGE TemplateHaskell #-}
+
+-- Checks that run on the Control Flow Graph (as opposed to the AST)
+-- This is scaffolding for a work in progress.
+
+module ShellCheck.Checks.ControlFlow (checker, optionalChecks, ShellCheck.Checks.ControlFlow.runTests) where
+
+import ShellCheck.AST
+import ShellCheck.ASTLib
+import ShellCheck.CFG hiding (cfgAnalysis)
+import ShellCheck.CFGAnalysis
+import ShellCheck.AnalyzerLib
+import ShellCheck.Data
+import ShellCheck.Interface
+
+import Control.Monad
+import Control.Monad.Reader
+import Data.Graph.Inductive.Graph
+import qualified Data.Map as M
+import qualified Data.Set as S
+import Data.List
+import Data.Maybe
+
+import Test.QuickCheck.All (forAllProperties)
+import Test.QuickCheck.Test (quickCheckWithResult, stdArgs, maxSuccess)
+
+
+optionalChecks :: [CheckDescription]
+optionalChecks = []
+
+-- A check that runs on the entire graph
+type ControlFlowCheck = Analysis
+-- A check invoked once per node, with its (pre,post) data
+type ControlFlowNodeCheck = LNode CFNode -> (ProgramState, ProgramState) -> Analysis
+-- A check invoked once per effect, with its node's (pre,post) data
+type ControlFlowEffectCheck = IdTagged CFEffect -> Node -> (ProgramState, ProgramState) -> Analysis
+
+
+checker :: AnalysisSpec -> Parameters -> Checker
+checker spec params = Checker {
+    perScript = const $ sequence_ controlFlowChecks,
+    perToken = const $ return ()
+}
+
+controlFlowChecks :: [ControlFlowCheck]
+controlFlowChecks = [
+        runNodeChecks controlFlowNodeChecks
+    ]
+
+controlFlowNodeChecks :: [ControlFlowNodeCheck]
+controlFlowNodeChecks = [
+    runEffectChecks controlFlowEffectChecks
+    ]
+
+controlFlowEffectChecks :: [ControlFlowEffectCheck]
+controlFlowEffectChecks = [
+    ]
+
+runNodeChecks :: [ControlFlowNodeCheck] -> ControlFlowCheck
+runNodeChecks perNode = do
+    cfg <- asks cfgAnalysis
+    mapM_ runOnAll cfg
+  where
+    getData datas n@(node, label) = do
+        (pre, post) <- M.lookup node datas
+        return (n, (pre, post))
+
+    runOn :: (LNode CFNode, (ProgramState, ProgramState)) -> Analysis
+    runOn (node, prepost) = mapM_ (\c -> c node prepost) perNode
+    runOnAll cfg = mapM_ runOn $ mapMaybe (getData $ nodeToData cfg) $ labNodes (graph cfg)
+
+runEffectChecks :: [ControlFlowEffectCheck] -> ControlFlowNodeCheck
+runEffectChecks list = checkNode
+  where
+    checkNode (node, label) prepost =
+        case label of
+            CFApplyEffects effects -> mapM_ (\effect -> mapM_ (\c -> c effect node prepost) list) effects
+            _ -> return ()
+
+
+return []
+runTests =  $( [| $(forAllProperties) (quickCheckWithResult (stdArgs { maxSuccess = 1 }) ) |])

src/ShellCheck/Checks/ShellSupport.hs

@@ -1,5 +1,5 @@
 {-
-    Copyright 2012-2016 Vidar Holen
+    Copyright 2012-2020 Vidar Holen
 
     This file is part of ShellCheck.
     https://www.shellcheck.net
@@ -19,17 +19,20 @@
 -}
 {-# LANGUAGE TemplateHaskell #-}
 {-# LANGUAGE FlexibleContexts #-}
+{-# LANGUAGE ViewPatterns #-}
 module ShellCheck.Checks.ShellSupport (checker , ShellCheck.Checks.ShellSupport.runTests) where
 
 import ShellCheck.AST
 import ShellCheck.ASTLib
 import ShellCheck.AnalyzerLib
 import ShellCheck.Interface
+import ShellCheck.Prelude
 import ShellCheck.Regex
 
 import Control.Monad
 import Control.Monad.RWS
 import Data.Char
+import Data.Functor.Identity
 import Data.List
 import Data.Maybe
 import qualified Data.Map as Map
@@ -58,6 +61,9 @@ checks = [
     ,checkBraceExpansionVars
     ,checkMultiDimensionalArrays
     ,checkPS1Assignments
+    ,checkMultipleBangs
+    ,checkBangAfterPipe
+    ,checkNegatedUnaryOps
     ]
 
 testChecker (ForShell _ t) =
@@ -71,22 +77,24 @@ verifyNot c s = producesComments (testChecker c) s == Just False
 prop_checkForDecimals1 = verify checkForDecimals "((3.14*c))"
 prop_checkForDecimals2 = verify checkForDecimals "foo[1.2]=bar"
 prop_checkForDecimals3 = verifyNot checkForDecimals "declare -A foo; foo[1.2]=bar"
-checkForDecimals = ForShell [Sh, Dash, Bash] f
+checkForDecimals = ForShell [Sh, Dash, BusyboxSh, Bash] f
   where
-    f t@(TA_Expansion id _) = potentially $ do
-        str <- getLiteralString t
-        first <- str !!! 0
-        guard $ isDigit first && '.' `elem` str
+    f t@(TA_Expansion id _) = sequence_ $ do
+        first:rest <- getLiteralString t
+        guard $ isDigit first && '.' `elem` rest
         return $ err id 2079 "(( )) doesn't support decimals. Use bc or awk."
     f _ = return ()
 
 
 prop_checkBashisms = verify checkBashisms "while read a; do :; done < <(a)"
-prop_checkBashisms2 = verify checkBashisms "[ foo -nt bar ]"
+prop_checkBashisms2 = verifyNot checkBashisms "[ foo -nt bar ]"
 prop_checkBashisms3 = verify checkBashisms "echo $((i++))"
 prop_checkBashisms4 = verify checkBashisms "rm !(*.hs)"
 prop_checkBashisms5 = verify checkBashisms "source file"
 prop_checkBashisms6 = verify checkBashisms "[ \"$a\" == 42 ]"
+prop_checkBashisms6b = verify checkBashisms "test \"$a\" == 42"
+prop_checkBashisms6c = verify checkBashisms "[ foo =~ bar ]"
+prop_checkBashisms6d = verify checkBashisms "test foo =~ bar"
 prop_checkBashisms7 = verify checkBashisms "echo ${var[1]}"
 prop_checkBashisms8 = verify checkBashisms "echo ${!var[@]}"
 prop_checkBashisms9 = verify checkBashisms "echo ${!var*}"
@@ -102,6 +110,7 @@ prop_checkBashisms18= verify checkBashisms "foo &> /dev/null"
 prop_checkBashisms19 = verify checkBashisms "foo > file*.txt"
 prop_checkBashisms20 = verify checkBashisms "read -ra foo"
 prop_checkBashisms21 = verify checkBashisms "[ -a foo ]"
+prop_checkBashisms21b = verify checkBashisms "test -a foo"
 prop_checkBashisms22 = verifyNot checkBashisms "[ foo -a bar ]"
 prop_checkBashisms23 = verify checkBashisms "trap mything ERR INT"
 prop_checkBashisms24 = verifyNot checkBashisms "trap mything INT TERM"
@@ -133,6 +142,8 @@ prop_checkBashisms49= verify checkBashisms "#!/bin/dash\necho $MACHTYPE"
 prop_checkBashisms50 = verify checkBashisms "#!/bin/sh\ncmd >& file"
 prop_checkBashisms51 = verifyNot checkBashisms "#!/bin/sh\ncmd 2>&1"
 prop_checkBashisms52 = verifyNot checkBashisms "#!/bin/sh\ncmd >&2"
+prop_checkBashisms52b = verifyNot checkBashisms "#!/bin/sh\ncmd >& $var"
+prop_checkBashisms52c = verify checkBashisms "#!/bin/sh\ncmd >& $dir/$var"
 prop_checkBashisms53 = verifyNot checkBashisms "#!/bin/sh\nprintf -- -f\n"
 prop_checkBashisms54 = verify checkBashisms "#!/bin/sh\nfoo+=bar"
 prop_checkBashisms55 = verify checkBashisms "#!/bin/sh\necho ${@%foo}"
@@ -177,110 +188,153 @@ prop_checkBashisms93 = verify checkBashisms "#!/bin/sh\necho $(( 10#$(date +%m)
 prop_checkBashisms94 = verify checkBashisms "#!/bin/sh\n[ -v var ]"
 prop_checkBashisms95 = verify checkBashisms "#!/bin/sh\necho $_"
 prop_checkBashisms96 = verifyNot checkBashisms "#!/bin/dash\necho $_"
-checkBashisms = ForShell [Sh, Dash] $ \t -> do
+prop_checkBashisms97 = verify checkBashisms "#!/bin/sh\necho ${var,}"
+prop_checkBashisms98 = verify checkBashisms "#!/bin/sh\necho ${var^^}"
+prop_checkBashisms99 = verify checkBashisms "#!/bin/dash\necho [^f]oo"
+prop_checkBashisms100 = verify checkBashisms "read -r"
+prop_checkBashisms101 = verify checkBashisms "read"
+prop_checkBashisms102 = verifyNot checkBashisms "read -r foo"
+prop_checkBashisms103 = verifyNot checkBashisms "read foo"
+prop_checkBashisms104 = verifyNot checkBashisms "read ''"
+prop_checkBashisms105 = verifyNot checkBashisms "#!/bin/busybox sh\nset -o pipefail"
+prop_checkBashisms106 = verifyNot checkBashisms "#!/bin/busybox sh\nx=x\n[[ \"$x\" = \"$x\" ]]"
+prop_checkBashisms107 = verifyNot checkBashisms "#!/bin/busybox sh\nx=x\n[ \"$x\" == \"$x\" ]"
+prop_checkBashisms108 = verifyNot checkBashisms "#!/bin/busybox sh\necho magic &> /dev/null"
+prop_checkBashisms109 = verifyNot checkBashisms "#!/bin/busybox sh\ntrap stop EXIT SIGTERM"
+prop_checkBashisms110 = verifyNot checkBashisms "#!/bin/busybox sh\nsource /dev/null"
+prop_checkBashisms111 = verify checkBashisms "#!/bin/dash\nx='test'\n${x:0:3}" -- SC3057
+prop_checkBashisms112 = verifyNot checkBashisms "#!/bin/busybox sh\nx='test'\n${x:0:3}" -- SC3057
+prop_checkBashisms113 = verify checkBashisms "#!/bin/dash\nx='test'\n${x/st/xt}" -- SC3060
+prop_checkBashisms114 = verifyNot checkBashisms "#!/bin/busybox sh\nx='test'\n${x/st/xt}" -- SC3060
+prop_checkBashisms115 = verify checkBashisms "#!/bin/busybox sh\nx='test'\n${!x}" -- SC3053
+prop_checkBashisms116 = verify checkBashisms "#!/bin/busybox sh\nx='test'\n${x[1]}" -- SC3054
+prop_checkBashisms117 = verify checkBashisms "#!/bin/busybox sh\nx='test'\n${!x[@]}" -- SC3055
+prop_checkBashisms118 = verify checkBashisms "#!/bin/busybox sh\nxyz=1\n${!x*}" -- SC3056
+prop_checkBashisms119 = verify checkBashisms "#!/bin/busybox sh\nx='test'\n${x^^[t]}" -- SC3059
+prop_checkBashisms120 = verify checkBashisms "#!/bin/sh\n[ x == y ]"
+prop_checkBashisms121 = verifyNot checkBashisms "#!/bin/sh\n# shellcheck shell=busybox\n[ x == y ]"
+prop_checkBashisms122 = verify checkBashisms "#!/bin/dash\n$'a'"
+prop_checkBashisms123 = verifyNot checkBashisms "#!/bin/busybox sh\n$'a'"
+prop_checkBashisms124 = verify checkBashisms "#!/bin/dash\ntype -p test"
+prop_checkBashisms125 = verifyNot checkBashisms "#!/bin/busybox sh\ntype -p test"
+prop_checkBashisms126 = verifyNot checkBashisms "#!/bin/busybox sh\nread -p foo -r bar"
+prop_checkBashisms127 = verifyNot checkBashisms "#!/bin/busybox sh\necho -ne foo"
+prop_checkBashisms128 = verify checkBashisms "#!/bin/dash\ntype -p test"
+prop_checkBashisms129 = verify checkBashisms "#!/bin/sh\n[ -k /tmp ]"
+prop_checkBashisms130 = verifyNot checkBashisms "#!/bin/dash\ntest -k /tmp"
+prop_checkBashisms131 = verify checkBashisms "#!/bin/sh\n[ -o errexit ]"
+checkBashisms = ForShell [Sh, Dash, BusyboxSh] $ \t -> do
     params <- ask
     kludge params t
  where
   -- This code was copy-pasted from Analytics where params was a variable
   kludge params = bashism
    where
-    isDash = shellType params == Dash
-    warnMsg id s =
+    isBusyboxSh = shellType params == BusyboxSh
+    isDash = shellType params == Dash || isBusyboxSh
+    warnMsg id code s =
         if isDash
-        then warn id 2169 $ "In dash, " ++ s ++ " not supported."
-        else warn id 2039 $ "In POSIX sh, " ++ s ++ " undefined."
+        then err  id code $ "In dash, " ++ s ++ " not supported."
+        else warn id code $ "In POSIX sh, " ++ s ++ " undefined."
+    asStr = getLiteralString
+
+    bashism (T_ProcSub id _ _) = warnMsg id 3001 "process substitution is"
+    bashism (T_Extglob id _ _) = warnMsg id 3002 "extglob is"
+    bashism (T_DollarSingleQuoted id _) =
+        unless isBusyboxSh $ warnMsg id 3003 "$'..' is"
+    bashism (T_DollarDoubleQuoted id _) = warnMsg id 3004 "$\"..\" is"
+    bashism (T_ForArithmetic id _ _ _ _) = warnMsg id 3005 "arithmetic for loops are"
+    bashism (T_Arithmetic id _) = warnMsg id 3006 "standalone ((..)) is"
+    bashism (T_DollarBracket id _) = warnMsg id 3007 "$[..] in place of $((..)) is"
+    bashism (T_SelectIn id _ _ _) = warnMsg id 3008 "select loops are"
+    bashism (T_BraceExpansion id _) = warnMsg id 3009 "brace expansion is"
+    bashism (T_Condition id DoubleBracket _) =
+        unless isBusyboxSh $ warnMsg id 3010 "[[ ]] is"
+    bashism (T_HereString id _) = warnMsg id 3011 "here-strings are"
+
+    bashism (TC_Binary id _ op _ _) =
+        checkTestOp bashismBinaryTestFlags op id
+    bashism (T_SimpleCommand id _ [asStr -> Just "test", lhs, asStr -> Just op, rhs]) =
+        checkTestOp bashismBinaryTestFlags op id
+    bashism (TC_Unary id _ op _) =
+        checkTestOp bashismUnaryTestFlags op id
+    bashism (T_SimpleCommand id _ [asStr -> Just "test", asStr -> Just op, _]) =
+        checkTestOp bashismUnaryTestFlags op id
 
-    bashism (T_ProcSub id _ _) = warnMsg id "process substitution is"
-    bashism (T_Extglob id _ _) = warnMsg id "extglob is"
-    bashism (T_DollarSingleQuoted id _) = warnMsg id "$'..' is"
-    bashism (T_DollarDoubleQuoted id _) = warnMsg id "$\"..\" is"
-    bashism (T_ForArithmetic id _ _ _ _) = warnMsg id "arithmetic for loops are"
-    bashism (T_Arithmetic id _) = warnMsg id "standalone ((..)) is"
-    bashism (T_DollarBracket id _) = warnMsg id "$[..] in place of $((..)) is"
-    bashism (T_SelectIn id _ _ _) = warnMsg id "select loops are"
-    bashism (T_BraceExpansion id _) = warnMsg id "brace expansion is"
-    bashism (T_Condition id DoubleBracket _) = warnMsg id "[[ ]] is"
-    bashism (T_HereString id _) = warnMsg id "here-strings are"
-    bashism (TC_Binary id SingleBracket op _ _)
-        | op `elem` [ "<", ">", "\\<", "\\>", "<=", ">=", "\\<=", "\\>="] =
-            unless isDash $ warnMsg id $ "lexicographical " ++ op ++ " is"
-    bashism (TC_Binary id SingleBracket op _ _)
-        | op `elem` [ "-nt", "-ef" ] =
-            unless isDash $ warnMsg id $ op ++ " is"
-    bashism (TC_Binary id SingleBracket "==" _ _) =
-            warnMsg id "== in place of = is"
-    bashism (TC_Binary id SingleBracket "=~" _ _) =
-            warnMsg id "=~ regex matching is"
-    bashism (TC_Unary id SingleBracket "-v" _) =
-            warnMsg id "unary -v (in place of [ -n \"${var+x}\" ]) is"
-    bashism (TC_Unary id _ "-a" _) =
-            warnMsg id "unary -a in place of -e is"
     bashism (TA_Unary id op _)
         | op `elem` [ "|++", "|--", "++|", "--|"] =
-            warnMsg id $ filter (/= '|') op ++ " is"
-    bashism (TA_Binary id "**" _ _) = warnMsg id "exponentials are"
-    bashism (T_FdRedirect id "&" (T_IoFile _ (T_Greater _) _)) = warnMsg id "&> is"
-    bashism (T_FdRedirect id "" (T_IoFile _ (T_GREATAND _) _)) = warnMsg id ">& is"
-    bashism (T_FdRedirect id ('{':_) _) = warnMsg id "named file descriptors are"
+            warnMsg id 3018 $ filter (/= '|') op ++ " is"
+    bashism (TA_Binary id "**" _ _) = warnMsg id 3019 "exponentials are"
+    bashism (T_FdRedirect id "&" (T_IoFile _ (T_Greater _) _)) =
+        unless isBusyboxSh $ warnMsg id 3020 "&> is"
+    bashism (T_FdRedirect id "" (T_IoFile _ (T_GREATAND _) file)) =
+        unless (all isDigit $ onlyLiteralString file) $ warnMsg id 3021 ">& filename (as opposed to >& fd) is"
+    bashism (T_FdRedirect id ('{':_) _) = warnMsg id 3022 "named file descriptors are"
     bashism (T_FdRedirect id num _)
-        | all isDigit num && length num > 1 = warnMsg id "FDs outside 0-9 are"
+        | all isDigit num && length num > 1 = warnMsg id 3023 "FDs outside 0-9 are"
     bashism (T_Assignment id Append _ _ _) =
-        warnMsg id "+= is"
+        warnMsg id 3024 "+= is"
     bashism (T_IoFile id _ word) | isNetworked =
-            warnMsg id "/dev/{tcp,udp} is"
+            warnMsg id 3025 "/dev/{tcp,udp} is"
         where
             file = onlyLiteralString word
             isNetworked = any (`isPrefixOf` file) ["/dev/tcp", "/dev/udp"]
     bashism (T_Glob id str) | "[^" `isInfixOf` str =
-            warnMsg id "^ in place of ! in glob bracket expressions is"
+            warnMsg id 3026 "^ in place of ! in glob bracket expressions is"
 
     bashism t@(TA_Variable id str _) | isBashVariable str =
-        warnMsg id $ str ++ " is"
+        warnMsg id 3028 $ str ++ " is"
 
     bashism t@(T_DollarBraced id _ token) = do
-        mapM_ check expansion
+        unless isBusyboxSh $ mapM_ check simpleExpansions
+        mapM_ check advancedExpansions
         when (isBashVariable var) $
-                    warnMsg id $ var ++ " is"
+            warnMsg id 3028 $ var ++ " is"
       where
-        str = bracedString t
+        str = concat $ oversimplify token
         var = getBracedReference str
-        check (regex, feature) =
-            when (isJust $ matchRegex regex str) $ warnMsg id feature
+        check (regex, code, feature) =
+            when (isJust $ matchRegex regex str) $ warnMsg id code feature
 
     bashism t@(T_Pipe id "|&") =
-        warnMsg id "|& in place of 2>&1 | is"
+        warnMsg id 3029 "|& in place of 2>&1 | is"
     bashism (T_Array id _) =
-        warnMsg id "arrays are"
+        warnMsg id 3030 "arrays are"
     bashism (T_IoFile id _ t) | isGlob t =
-        warnMsg id "redirecting to/from globs is"
+        warnMsg id 3031 "redirecting to/from globs is"
     bashism (T_CoProc id _ _) =
-        warnMsg id "coproc is"
+        warnMsg id 3032 "coproc is"
 
     bashism (T_Function id _ _ str _) | not (isVariableName str) =
-        warnMsg id "naming functions outside [a-zA-Z_][a-zA-Z0-9_]* is"
+        warnMsg id 3033 "naming functions outside [a-zA-Z_][a-zA-Z0-9_]* is"
 
     bashism (T_DollarExpansion id [x]) | isOnlyRedirection x =
-        warnMsg id "$(<file) to read files is"
+        warnMsg id 3034 "$(<file) to read files is"
     bashism (T_Backticked id [x]) | isOnlyRedirection x =
-        warnMsg id "`<file` to read files is"
+        warnMsg id 3035 "`<file` to read files is"
 
     bashism t@(T_SimpleCommand _ _ (cmd:arg:_))
         | t `isCommand` "echo" && argString `matches` flagRegex =
-            if isDash
+            if isBusyboxSh
+            then
+                unless (argString `matches` busyboxFlagRegex) $
+                    warnMsg (getId arg) 3036 "echo flags besides -n and -e"
+            else if isDash
             then
                 when (argString /= "-n") $
-                    warnMsg (getId arg) "echo flags besides -n"
+                    warnMsg (getId arg) 3036 "echo flags besides -n"
             else
-                warnMsg (getId arg) "echo flags are"
+                warnMsg (getId arg) 3037 "echo flags are"
       where
           argString = concat $ oversimplify arg
           flagRegex = mkRegex "^-[eEsn]+$"
+          busyboxFlagRegex = mkRegex "^-[en]+$"
 
     bashism t@(T_SimpleCommand _ _ (cmd:arg:_))
-        | t `isCommand` "exec" && "-" `isPrefixOf` concat (oversimplify arg) =
-            warnMsg (getId arg) "exec flags are"
+        | getLiteralString cmd == Just "exec" && "-" `isPrefixOf` concat (oversimplify arg) =
+            warnMsg (getId arg) 3038 "exec flags are"
     bashism t@(T_SimpleCommand id _ _)
-        | t `isCommand` "let" = warnMsg id "'let' is"
+        | t `isCommand` "let" = warnMsg id 3039 "'let' is"
     bashism t@(T_SimpleCommand _ _ (cmd:args))
         | t `isCommand` "set" = unless isDash $
             checkOptions $ getLiteralArgs args
@@ -288,16 +342,17 @@ checkBashisms = ForShell [Sh, Dash] $ \t -> do
         -- Get the literal options from a list of arguments,
         -- up until the first non-literal one
         getLiteralArgs :: [Token] -> [(Id, String)]
-        getLiteralArgs (first:rest) = fromMaybe [] $ do
-            str <- getLiteralString first
-            return $ (getId first, str) : getLiteralArgs rest
-        getLiteralArgs [] = []
+        getLiteralArgs = foldr go []
+          where
+            go first rest = case getLiteralString first of
+                Just str -> (getId first, str) : rest
+                Nothing -> []
 
         -- Check a flag-option pair (such as -o errexit)
         checkOptions (flag@(fid,flag') : opt@(oid,opt') : rest)
             | flag' `matches` oFlagRegex = do
                 when (opt' `notElem` longOptions) $
-                  warnMsg oid $ "set option " <> opt' <> " is"
+                  warnMsg oid 3040 $ "set option " <> opt' <> " is"
                 checkFlags (flag:rest)
             | otherwise = checkFlags (flag:opt:rest)
         checkOptions (flag:rest) = checkFlags (flag:rest)
@@ -310,10 +365,10 @@ checkBashisms = ForShell [Sh, Dash] $ \t -> do
                 unless (flag' `matches` validFlagsRegex) $
                   forM_ (tail flag') $ \letter ->
                     when (letter `notElem` optionsSet) $
-                      warnMsg fid $ "set flag " <> ('-':letter:" is")
+                      warnMsg fid 3041 $ "set flag " <> ('-':letter:" is")
                 checkOptions rest
             | beginsWithDoubleDash flag' = do
-                warnMsg fid $ "set flag " <> flag' <> " is"
+                warnMsg fid 3042 $ "set flag " <> flag' <> " is"
                 checkOptions rest
             -- Either a word that doesn't start with a dash, or simply '--',
             -- so stop checking.
@@ -335,44 +390,51 @@ checkBashisms = ForShell [Sh, Dash] $ \t -> do
         let name = fromMaybe "" $ getCommandName t
             flags = getLeadingFlags t
         in do
+            when (name == "local" && not isDash) $
+                -- This is so commonly accepted that we'll make it a special case
+                warnMsg id 3043 $ "'local' is"
             when (name `elem` unsupportedCommands) $
-                warnMsg id $ "'" ++ name ++ "' is"
-            potentially $ do
+                warnMsg id 3044 $ "'" ++ name ++ "' is"
+            sequence_ $ do
                 allowed' <- Map.lookup name allowedFlags
                 allowed <- allowed'
-                (word, flag) <- listToMaybe $
-                    filter (\x -> (not . null . snd $ x) && snd x `notElem` allowed) flags
-                return . warnMsg (getId word) $ name ++ " -" ++ flag ++ " is"
+                (word, flag) <- find
+                    (\x -> (not . null . snd $ x) && snd x `notElem` allowed) flags
+                return . warnMsg (getId word) 3045 $ name ++ " -" ++ flag ++ " is"
 
-            when (name == "source") $ warnMsg id "'source' in place of '.' is"
+            when (name == "source" && not isBusyboxSh) $
+                warnMsg id 3046 "'source' in place of '.' is"
             when (name == "trap") $
                 let
-                    check token = potentially $ do
+                    check token = sequence_ $ do
                         str <- getLiteralString token
                         let upper = map toUpper str
                         return $ do
                             when (upper `elem` ["ERR", "DEBUG", "RETURN"]) $
-                                warnMsg (getId token) $ "trapping " ++ str ++ " is"
-                            when ("SIG" `isPrefixOf` upper) $
-                                warnMsg (getId token)
+                                warnMsg (getId token) 3047 $ "trapping " ++ str ++ " is"
+                            when (not isBusyboxSh && "SIG" `isPrefixOf` upper) $
+                                warnMsg (getId token) 3048
                                     "prefixing signal names with 'SIG' is"
                             when (not isDash && upper /= str) $
-                                warnMsg (getId token)
+                                warnMsg (getId token) 3049
                                     "using lower/mixed case for signal names is"
                 in
                     mapM_ check (drop 1 rest)
 
-            when (name == "printf") $ potentially $ do
+            when (name == "printf") $ sequence_ $ do
                 format <- rest !!! 0  -- flags are covered by allowedFlags
                 let literal = onlyLiteralString format
                 guard $ "%q" `isInfixOf` literal
-                return $ warnMsg (getId format) "printf %q is"
+                return $ warnMsg (getId format) 3050 "printf %q is"
+
+            when (name == "read" && all isFlag rest) $
+                warnMsg (getId cmd) 3061 "read without a variable is"
       where
         unsupportedCommands = [
             "let", "caller", "builtin", "complete", "compgen", "declare", "dirs", "disown",
             "enable", "mapfile", "readarray", "pushd", "popd", "shopt", "suspend",
             "typeset"
-            ] ++ if not isDash then ["local"] else []
+            ]
         allowedFlags = Map.fromList [
             ("cd", Just ["L", "P"]),
             ("exec", Just []),
@@ -380,38 +442,48 @@ checkBashisms = ForShell [Sh, Dash] $ \t -> do
             ("hash", Just $ if isDash then ["r", "v"] else ["r"]),
             ("jobs", Just ["l", "p"]),
             ("printf", Just []),
-            ("read", Just $ if isDash then ["r", "p"] else ["r"]),
+            ("read", Just $ if isDash || isBusyboxSh then ["r", "p"] else ["r"]),
             ("readonly", Just ["p"]),
             ("trap", Just []),
-            ("type", Just []),
+            ("type", Just $ if isBusyboxSh then ["p"] else []),
             ("ulimit", if isDash then Nothing else Just ["f"]),
             ("umask", Just ["S"]),
             ("unset", Just ["f", "v"]),
             ("wait", Just [])
             ]
-    bashism t@(T_SourceCommand id src _) =
-        let name = fromMaybe "" $ getCommandName src
-        in when (name == "source") $ warnMsg id "'source' in place of '.' is"
-    bashism (TA_Expansion _ (T_Literal id str : _)) | str `matches` radix =
-        when (str `matches` radix) $ warnMsg id "arithmetic base conversion is"
+    bashism t@(T_SourceCommand id src _)
+      | getCommandName src == Just "source" =
+          unless isBusyboxSh $
+            warnMsg id 3051 "'source' in place of '.' is"
+    bashism (TA_Expansion _ (T_Literal id str : _))
+        | str `matches` radix = warnMsg id 3052 "arithmetic base conversion is"
       where
         radix = mkRegex "^[0-9]+#"
     bashism _ = return ()
 
     varChars="_0-9a-zA-Z"
-    expansion = let re = mkRegex in [
-        (re $ "^![" ++ varChars ++ "]", "indirect expansion is"),
-        (re $ "^[" ++ varChars ++ "]+\\[.*\\]$", "array references are"),
-        (re $ "^![" ++ varChars ++ "]+\\[[*@]]$", "array key expansion is"),
-        (re $ "^![" ++ varChars ++ "]+[*@]$", "name matching prefixes are"),
-        (re $ "^[" ++ varChars ++ "*@]+:[^-=?+]", "string indexing is"),
-        (re $ "^([*@][%#]|#[@*])", "string operations on $@/$* are"),
-        (re $ "^[" ++ varChars ++ "*@]+(\\[.*\\])?/", "string replacement is")
+    advancedExpansions = let re = mkRegex in [
+        (re $ "^![" ++ varChars ++ "]", 3053, "indirect expansion is"),
+        (re $ "^[" ++ varChars ++ "]+\\[.*\\]$", 3054, "array references are"),
+        (re $ "^![" ++ varChars ++ "]+\\[[*@]]$", 3055, "array key expansion is"),
+        (re $ "^![" ++ varChars ++ "]+[*@]$", 3056, "name matching prefixes are"),
+        (re $ "^[" ++ varChars ++ "*@]+(\\[.*\\])?[,^]", 3059, "case modification is")
+        ]
+    simpleExpansions = let re = mkRegex in [
+        (re $ "^[" ++ varChars ++ "*@]+:[^-=?+]", 3057, "string indexing is"),
+        (re $ "^([*@][%#]|#[@*])", 3058, "string operations on $@/$* are"),
+        (re $ "^[" ++ varChars ++ "*@]+(\\[.*\\])?/", 3060, "string replacement is")
         ]
     bashVars = [
+        -- This list deliberately excludes $BASH_VERSION as it's often used
+        -- for shell identification.
         "OSTYPE", "MACHTYPE", "HOSTTYPE", "HOSTNAME",
         "DIRSTACK", "EUID", "UID", "SHLVL", "PIPESTATUS", "SHELLOPTS",
-        "_"
+        "_", "BASHOPTS", "BASHPID", "BASH_ALIASES", "BASH_ARGC",
+        "BASH_ARGV", "BASH_ARGV0", "BASH_CMDS", "BASH_COMMAND",
+        "BASH_EXECUTION_STRING", "BASH_LINENO", "BASH_REMATCH", "BASH_SOURCE",
+        "BASH_SUBSHELL", "BASH_VERSINFO", "EPOCHREALTIME", "EPOCHSECONDS",
+        "FUNCNAME", "GROUPS", "MACHTYPE", "MAPFILE"
         ]
     bashDynamicVars = [ "RANDOM", "SECONDS" ]
     dashVars = [ "_" ]
@@ -425,6 +497,50 @@ checkBashisms = ForShell [Sh, Dash] $ \t -> do
                 Assignment (_, _, name, _) -> name == var
                 _ -> False
 
+    checkTestOp table op id = sequence_ $ do
+        (code, shells, msg) <- Map.lookup op table
+        guard . not $ shellType params `elem` shells
+        return $ warnMsg id code (msg op)
+
+
+buildTestFlagMap list = Map.fromList $ concatMap (\(x,y) -> map (\c -> (c,y)) x) list
+bashismBinaryTestFlags = buildTestFlagMap [
+    -- ([list of applicable flags],
+    --     (error code, exempt shells, message builder :: String -> String)),
+    --
+    -- Distinct error codes allow the wiki to give more helpful, targeted
+    -- information.
+    (["<", ">", "\\<", "\\>", "<=", ">=", "\\<=", "\\>="],
+        (3012, [Dash, BusyboxSh], \op -> "lexicographical " ++ op ++ " is")),
+    (["=="],
+        (3014, [BusyboxSh], \op -> op ++ " in place of = is")),
+    (["=~"],
+        (3015, [], \op -> op ++ " regex matching is")),
+
+    ([], (0,[],const ""))
+  ]
+bashismUnaryTestFlags = buildTestFlagMap [
+    (["-v"],
+        (3016, [], \op -> "test " ++ op ++ " (in place of [ -n \"${var+x}\" ]) is")),
+    (["-a"],
+        (3017, [], \op -> "unary " ++ op ++ " in place of -e is")),
+    (["-o"],
+        (3062, [], \op -> "test " ++ op ++ " to check options is")),
+    (["-R"],
+        (3063, [], \op -> "test " ++ op ++ " and namerefs in general are")),
+    (["-N"],
+        (3064, [], \op -> "test " ++ op ++ " is")),
+    (["-k"],
+        (3065, [Dash, BusyboxSh], \op -> "test " ++ op ++ " is")),
+    (["-G"],
+        (3066, [Dash, BusyboxSh], \op -> "test " ++ op ++ " is")),
+    (["-O"],
+        (3067, [Dash, BusyboxSh], \op -> "test " ++ op ++ " is")),
+
+    ([], (0,[],const ""))
+  ]
+
+
 prop_checkEchoSed1 = verify checkEchoSed "FOO=$(echo \"$cow\" | sed 's/foo/bar/g')"
 prop_checkEchoSed1b = verify checkEchoSed "FOO=$(sed 's/foo/bar/g' <<< \"$cow\")"
 prop_checkEchoSed2 = verify checkEchoSed "rm $(echo $cow | sed -e 's,foo,bar,')"
@@ -456,11 +572,10 @@ checkEchoSed = ForShell [Bash, Ksh] f
 
     -- This should have used backreferences, but TDFA doesn't support them
     sedRe = mkRegex "^s(.)([^\n]*)g?$"
-    isSimpleSed s = fromMaybe False $ do
-        [first,rest] <- matchRegex sedRe s
-        let delimiters = filter (== head first) rest
+    isSimpleSed s = isJust $ do
+        [h:_,rest] <- matchRegex sedRe s
+        let delimiters = filter (== h) rest
         guard $ length delimiters == 2
-        return True
     checkIn id s =
         when (isSimpleSed s) $
             style id 2001 "See if you can use ${variable//search/replace} instead."
@@ -487,11 +602,11 @@ checkBraceExpansionVars = ForShell [Bash] f
             T_DollarBraced {} -> return "$"
             T_DollarExpansion {} -> return "$"
             T_DollarArithmetic {} -> return "$"
-            otherwise -> return "-"
-    toString t = fromJust $ getLiteralStringExt literalExt t
+            _ -> return "-"
+    toString t = runIdentity $ getLiteralStringExt literalExt t
     isEvaled t = do
         cmd <- getClosestCommandM t
-        return $ isJust cmd && fromJust cmd `isUnqualifiedCommand` "eval"
+        return $ maybe False (`isUnqualifiedCommand` "eval") cmd
 
 
 prop_checkMultiDimensionalArrays1 = verify checkMultiDimensionalArrays "foo[a][b]=3"
@@ -506,13 +621,13 @@ checkMultiDimensionalArrays = ForShell [Bash] f
         case token of
             T_Assignment _ _ name (first:second:_) _ -> about second
             T_IndexedElement _ (first:second:_) _ -> about second
-            T_DollarBraced {} ->
-                when (isMultiDim token) $ about token
+            T_DollarBraced _ _ l ->
+                when (isMultiDim l) $ about token
             _ -> return ()
     about t = warn (getId t) 2180 "Bash does not support multidimensional arrays. Use 1D or associative arrays."
 
     re = mkRegex "^\\[.*\\]\\[.*\\]"  -- Fixme, this matches ${foo:- [][]} and such as well
-    isMultiDim t = getBracedModifier (bracedString t) `matches` re
+    isMultiDim l = getBracedModifier (concat $ oversimplify l) `matches` re
 
 prop_checkPS11 = verify checkPS1Assignments "PS1='\\033[1;35m\\$ '"
 prop_checkPS11a = verify checkPS1Assignments "export PS1='\\033[1;35m\\$ '"
@@ -541,5 +656,46 @@ checkPS1Assignments = ForShell [Bash] f
     escapeRegex = mkRegex "\\\\x1[Bb]|\\\\e|\x1B|\\\\033"
 
 
+prop_checkMultipleBangs1 = verify checkMultipleBangs "! ! true"
+prop_checkMultipleBangs2 = verifyNot checkMultipleBangs "! true"
+checkMultipleBangs = ForShell [Dash, BusyboxSh, Sh] f
+  where
+    f token = case token of
+        T_Banged id (T_Banged _ _) ->
+            err id 2325 "Multiple ! in front of pipelines are a bash/ksh extension. Use only 0 or 1."
+        _ -> return ()
+
+
+prop_checkBangAfterPipe1 = verify checkBangAfterPipe "true | ! true"
+prop_checkBangAfterPipe2 = verifyNot checkBangAfterPipe "true | ( ! true )"
+prop_checkBangAfterPipe3 = verifyNot checkBangAfterPipe "! ! true | true"
+checkBangAfterPipe = ForShell [Dash, BusyboxSh, Sh, Bash] f
+  where
+    f token = case token of
+        T_Pipeline _ _ cmds -> mapM_ check cmds
+        _ -> return ()
+
+    check token = case token of
+        T_Banged id _ ->
+            err id 2326 "! is not allowed in the middle of pipelines. Use command group as in cmd | { ! cmd; } if necessary."
+        _ -> return ()
+
+
+prop_checkNegatedUnaryOps1 = verify checkNegatedUnaryOps "[ ! -o braceexpand ]"
+prop_checkNegatedUnaryOps2 = verifyNot checkNegatedUnaryOps "[ -o braceexpand ]"
+prop_checkNegatedUnaryOps3 = verifyNot checkNegatedUnaryOps "[[ ! -o braceexpand ]]"
+prop_checkNegatedUnaryOps4 = verifyNot checkNegatedUnaryOps "! [ -o braceexpand ]"
+prop_checkNegatedUnaryOps5 = verify checkNegatedUnaryOps "[ ! -a file ]"
+checkNegatedUnaryOps = ForShell [Bash] f
+  where
+    f token = case token of
+        TC_Unary id SingleBracket "!" (TC_Unary _ _ op _) | op `elem` ["-a", "-o"] ->
+            err id 2332 $ msg op
+        _ -> return ()
+
+    msg "-o" = "[ ! -o opt ] is always true because -o becomes logical OR. Use [[ ]] or ! [ -o opt ]."
+    msg "-a" = "[ ! -a file ] is always true because -a becomes logical AND. Use -e instead."
+    msg _ = pleaseReport "unhandled negated unary message"
+
 return []
 runTests =  $( [| $(forAllProperties) (quickCheckWithResult (stdArgs { maxSuccess = 1 }) ) |])

src/ShellCheck/Data.hs

@@ -2,33 +2,55 @@ module ShellCheck.Data where
 
 import ShellCheck.Interface
 import Data.Version (showVersion)
-import Paths_ShellCheck (version)
 
+
+{-
+If you are here because you saw an error about Paths_ShellCheck in this file,
+simply comment out the import below and define the version as a constant string.
+
+Instead of:
+
+    import Paths_ShellCheck (version)
     shellcheckVersion = showVersion version
 
+Use:
+
+    -- import Paths_ShellCheck (version)
+    shellcheckVersion = "kludge"
+
+-}
+
+import Paths_ShellCheck (version)
+shellcheckVersion = showVersion version  -- VERSIONSTRING
+
+
 internalVariables = [
     -- Generic
     "", "_", "rest", "REST",
 
     -- Bash
     "BASH", "BASHOPTS", "BASHPID", "BASH_ALIASES", "BASH_ARGC",
-    "BASH_ARGV", "BASH_CMDS", "BASH_COMMAND", "BASH_EXECUTION_STRING",
-    "BASH_LINENO", "BASH_REMATCH", "BASH_SOURCE", "BASH_SUBSHELL",
-    "BASH_VERSINFO", "BASH_VERSION", "COMP_CWORD", "COMP_KEY",
-    "COMP_LINE", "COMP_POINT", "COMP_TYPE", "COMP_WORDBREAKS",
-    "COMP_WORDS", "COPROC", "DIRSTACK", "EUID", "FUNCNAME", "GROUPS",
-    "HISTCMD", "HOSTNAME", "HOSTTYPE", "LINENO", "MACHTYPE", "MAPFILE",
-    "OLDPWD", "OPTARG", "OPTIND", "OSTYPE", "PIPESTATUS", "PPID", "PWD",
-    "RANDOM", "READLINE_LINE", "READLINE_POINT", "REPLY", "SECONDS",
-    "SHELLOPTS", "SHLVL", "UID", "BASH_ENV", "BASH_XTRACEFD", "CDPATH",
-    "COLUMNS", "COMPREPLY", "EMACS", "ENV", "FCEDIT", "FIGNORE",
+    "BASH_ARGV", "BASH_ARGV0", "BASH_CMDS", "BASH_COMMAND",
+    "BASH_EXECUTION_STRING", "BASH_LINENO", "BASH_LOADABLES_PATH",
+    "BASH_REMATCH", "BASH_SOURCE", "BASH_SUBSHELL", "BASH_VERSINFO",
+    "BASH_VERSION", "COMP_CWORD", "COMP_KEY", "COMP_LINE", "COMP_POINT",
+    "COMP_TYPE", "COMP_WORDBREAKS", "COMP_WORDS", "COPROC", "DIRSTACK",
+    "EPOCHREALTIME", "EPOCHSECONDS", "EUID", "FUNCNAME", "GROUPS", "HISTCMD",
+    "HOSTNAME", "HOSTTYPE", "LINENO", "MACHTYPE", "MAPFILE", "OLDPWD",
+    "OPTARG", "OPTIND", "OSTYPE", "PIPESTATUS", "PPID", "PWD", "RANDOM",
+    "READLINE_ARGUMENT", "READLINE_LINE", "READLINE_MARK", "READLINE_POINT",
+    "REPLY", "SECONDS", "SHELLOPTS", "SHLVL", "SRANDOM", "UID", "BASH_COMPAT",
+    "BASH_ENV", "BASH_XTRACEFD", "CDPATH", "CHILD_MAX", "COLUMNS",
+    "COMPREPLY", "EMACS", "ENV", "EXECIGNORE", "FCEDIT", "FIGNORE",
     "FUNCNEST", "GLOBIGNORE", "HISTCONTROL", "HISTFILE", "HISTFILESIZE",
     "HISTIGNORE", "HISTSIZE", "HISTTIMEFORMAT", "HOME", "HOSTFILE", "IFS",
-    "IGNOREEOF", "INPUTRC", "LANG", "LC_ALL", "LC_COLLATE", "LC_CTYPE",
-    "LC_MESSAGES", "LC_MONETARY", "LC_NUMERIC", "LC_TIME", "LINES", "MAIL",
-    "MAILCHECK", "MAILPATH", "OPTERR", "PATH", "POSIXLY_CORRECT",
-    "PROMPT_COMMAND", "PROMPT_DIRTRIM", "PS1", "PS2", "PS3", "PS4", "SHELL",
-    "TIMEFORMAT", "TMOUT", "TMPDIR", "auto_resume", "histchars", "COPROC",
+    "IGNOREEOF", "INPUTRC", "INSIDE_EMACS", "LANG", "LC_ALL", "LC_COLLATE",
+    "LC_CTYPE", "LC_MESSAGES", "LC_MONETARY", "LC_NUMERIC", "LC_TIME",
+    "LINES", "MAIL", "MAILCHECK", "MAILPATH", "OPTERR", "PATH",
+    "POSIXLY_CORRECT", "PROMPT_COMMAND", "PROMPT_DIRTRIM", "PS0", "PS1",
+    "PS2", "PS3", "PS4", "SHELL", "TIMEFORMAT", "TMOUT", "TMPDIR",
+    "BASH_MONOSECONDS", "BASH_TRAPSIG", "GLOBSORT",
+    "auto_resume", "histchars",
 
     -- Other
     "USER", "TZ", "TERM", "LOGNAME", "LD_LIBRARY_PATH", "LANGUAGE", "DISPLAY",
@@ -41,15 +63,23 @@ internalVariables = [
     , "FLAGS_ARGC", "FLAGS_ARGV", "FLAGS_ERROR", "FLAGS_FALSE", "FLAGS_HELP",
     "FLAGS_PARENT", "FLAGS_RESERVED", "FLAGS_TRUE", "FLAGS_VERSION",
     "flags_error", "flags_return"
+
+    -- Bats
+    ,"stderr", "stderr_lines"
   ]
 
-specialVariablesWithoutSpaces = [
-    "$", "-", "?", "!", "#"
+specialIntegerVariables = [
+    "$", "?", "!", "#"
   ]
+
+specialVariablesWithoutSpaces = "-" : specialIntegerVariables
+
 variablesWithoutSpaces = specialVariablesWithoutSpaces ++ [
-    "BASHPID", "BASH_ARGC", "BASH_LINENO", "BASH_SUBSHELL", "EUID", "LINENO",
-    "OPTIND", "PPID", "RANDOM", "SECONDS", "SHELLOPTS", "SHLVL", "UID",
-    "COLUMNS", "HISTFILESIZE", "HISTSIZE", "LINES"
+    "BASHPID", "BASH_ARGC", "BASH_LINENO", "BASH_SUBSHELL", "EUID",
+    "EPOCHREALTIME", "EPOCHSECONDS", "LINENO", "OPTIND", "PPID", "RANDOM",
+    "READLINE_ARGUMENT", "READLINE_MARK", "READLINE_POINT", "SECONDS",
+    "SHELLOPTS", "SHLVL", "SRANDOM", "UID", "COLUMNS", "HISTFILESIZE",
+    "HISTSIZE", "LINES", "BASH_MONOSECONDS", "BASH_TRAPSIG"
 
     -- shflags
     , "FLAGS_ERROR", "FLAGS_FALSE", "FLAGS_TRUE"
@@ -95,10 +125,10 @@ commonCommands = [
 
 nonReadingCommands = [
     "alias", "basename", "bg", "cal", "cd", "chgrp", "chmod", "chown",
-    "cp", "du", "echo", "export", "false", "fg", "fuser", "getconf",
+    "cp", "du", "echo", "export", "fg", "fuser", "getconf",
     "getopt", "getopts", "ipcrm", "ipcs", "jobs", "kill", "ln", "ls",
     "locale", "mv", "printf", "ps", "pwd", "renice", "rm", "rmdir",
-    "set", "sleep", "touch", "trap", "true", "ulimit", "unalias", "uname"
+    "set", "sleep", "touch", "trap", "ulimit", "unalias", "uname"
     ]
 
 sampleWords = [
@@ -114,6 +144,10 @@ binaryTestOps = [
     "-gt", "-ge", "=~", ">", "<", "=", "\\<", "\\>", "\\<=", "\\>="
   ]
 
+arithmeticBinaryTestOps = [
+    "-eq", "-ne", "-lt", "-le", "-gt", "-ge"
+  ]
+
 unaryTestOps = [
     "!", "-a", "-b", "-c", "-d", "-e", "-f", "-g", "-h", "-L", "-k", "-p",
     "-r", "-s", "-S", "-t", "-u", "-w", "-x", "-O", "-G", "-N", "-z", "-n",
@@ -126,9 +160,18 @@ shellForExecutable name =
         "sh"    -> return Sh
         "bash"  -> return Bash
         "bats"  -> return Bash
+        "busybox"  -> return BusyboxSh -- Used for directives and --shell=busybox
+        "busybox sh"  -> return BusyboxSh
+        "busybox ash"  -> return BusyboxSh
         "dash"  -> return Dash
         "ash"   -> return Dash -- There's also a warning for this.
         "ksh"   -> return Ksh
         "ksh88" -> return Ksh
         "ksh93" -> return Ksh
-        otherwise -> Nothing
+        "oksh"  -> return Ksh
+        _ -> Nothing
+
+flagsForRead = "sreu:n:N:i:p:a:t:"
+flagsForMapfile = "d:n:O:s:u:C:c:t"
+
+declaringCommands = ["local", "declare", "export", "readonly", "typeset", "let"]

src/ShellCheck/Debug.hs

@@ -0,0 +1,313 @@
+{-
+
+This file contains useful functions for debugging and developing ShellCheck.
+
+To invoke them interactively, run:
+
+    cabal repl
+
+At the ghci prompt, enter:
+
+    :load ShellCheck.Debug
+
+You can now invoke the functions. Here are some examples:
+
+    shellcheckString "echo $1"
+    stringToAst "(( x+1 ))"
+    stringToCfg "if foo; then bar; else baz; fi"
+    writeFile "/tmp/test.dot" $ stringToCfgViz "while foo; do bar; done"
+
+The latter file can be rendered to png with GraphViz:
+
+    dot -Tpng /tmp/test.dot > /tmp/test.png
+
+To run all unit tests in a module:
+
+    ShellCheck.Parser.runTests
+    ShellCheck.Analytics.runTests
+
+To run a specific test:
+
+    :load ShellCheck.Analytics
+    prop_checkUuoc3
+
+If you make code changes, reload in seconds at any time with:
+
+    :r
+
+===========================================================================
+
+Crash course in printf debugging in Haskell:
+
+    import Debug.Trace
+
+    greet 0 = return ()
+    -- Print when a function is invoked
+    greet n | trace ("calling greet " ++ show n) False = undefined
+    greet n = do
+        putStrLn "Enter name"
+        name <- getLine
+        -- Print at some point in any monadic function
+        traceM $ "user entered " ++ name
+        putStrLn $ "Hello " ++ name
+        -- Print a value before passing it on
+        greet $ traceShowId (n - 1)
+
+
+===========================================================================
+
+If you want to invoke `ghci` directly, such as on `shellcheck.hs`, to
+debug all of ShellCheck including I/O, you may see an error like this:
+
+    src/ShellCheck/Data.hs:5:1: error:
+        Could not load module ‘Paths_ShellCheck’
+    it is a hidden module in the package ‘ShellCheck-0.8.0’
+
+This can easily be circumvented by running `./setgitversion` or manually
+editing src/ShellCheck/Data.hs to replace the auto-deduced version number
+with a constant string as indicated.
+
+Afterwards, you can run the ShellCheck tool, as if from the shell, with:
+
+    $ ghci shellcheck.hs
+    ghci> runMain ["-x", "file.sh"]
+
+-}
+
+module ShellCheck.Debug () where
+
+import ShellCheck.Analyzer
+import ShellCheck.AST
+import ShellCheck.CFG
+import ShellCheck.Checker
+import ShellCheck.CFGAnalysis as CF
+import ShellCheck.Interface
+import ShellCheck.Parser
+import ShellCheck.Prelude
+
+import Control.Monad
+import Control.Monad.Identity
+import Control.Monad.RWS
+import Control.Monad.Writer
+import Data.Graph.Inductive.Graph as G
+import Data.List
+import Data.Maybe
+import qualified Data.Map as M
+import qualified Data.Set as S
+
+
+-- Run all of ShellCheck (minus output formatters)
+shellcheckString :: String -> CheckResult
+shellcheckString scriptString =
+    runIdentity $ checkScript dummySystemInterface checkSpec
+  where
+    checkSpec :: CheckSpec
+    checkSpec = emptyCheckSpec {
+        csScript = scriptString
+    }
+
+dummySystemInterface :: SystemInterface Identity
+dummySystemInterface = mockedSystemInterface [
+    -- A tiny, fake filesystem for sourced files
+    ("lib/mylib1.sh", "foo=$(cat $1 | wc -l)"),
+    ("lib/mylib2.sh", "bar=42")
+    ]
+
+-- Parameters used when generating Control Flow Graphs
+cfgParams :: CFGParameters
+cfgParams = CFGParameters {
+    cfLastpipe = False,
+    cfPipefail = False
+}
+
+-- An example script to play with
+exampleScript :: String
+exampleScript = unlines [
+    "#!/bin/sh",
+    "count=0",
+    "for file in *",
+    "do",
+    "  (( count++ ))",
+    "done",
+    "echo $count"
+    ]
+
+-- Parse the script string into ShellCheck's ParseResult
+parseScriptString :: String -> ParseResult
+parseScriptString scriptString =
+    runIdentity $ parseScript dummySystemInterface parseSpec
+  where
+    parseSpec :: ParseSpec
+    parseSpec = newParseSpec {
+        psFilename = "myscript",
+        psScript = scriptString
+    }
+
+
+-- Parse the script string into an Abstract Syntax Tree
+stringToAst :: String -> Token
+stringToAst scriptString =
+    case maybeRoot of
+        Just root -> root
+        Nothing -> error $ "Script failed to parse: " ++ show parserWarnings
+  where
+    parseResult :: ParseResult
+    parseResult = parseScriptString scriptString
+
+    maybeRoot :: Maybe Token
+    maybeRoot = prRoot parseResult
+
+    parserWarnings :: [PositionedComment]
+    parserWarnings = prComments parseResult
+
+
+astToCfgResult :: Token -> CFGResult
+astToCfgResult = buildGraph cfgParams
+
+astToDfa :: Token -> CFGAnalysis
+astToDfa = analyzeControlFlow cfgParams
+
+astToCfg :: Token -> CFGraph
+astToCfg = cfGraph . astToCfgResult
+
+stringToCfg :: String -> CFGraph
+stringToCfg = astToCfg . stringToAst
+
+stringToDfa :: String -> CFGAnalysis
+stringToDfa = astToDfa . stringToAst
+
+cfgToGraphViz :: CFGraph -> String
+cfgToGraphViz = cfgToGraphVizWith show
+
+stringToCfgViz :: String -> String
+stringToCfgViz = cfgToGraphViz . stringToCfg
+
+stringToDfaViz :: String -> String
+stringToDfaViz = dfaToGraphViz . stringToDfa
+
+-- Dump a Control Flow Graph as GraphViz with extended information
+stringToDetailedCfgViz :: String -> String
+stringToDetailedCfgViz scriptString = cfgToGraphVizWith nodeLabel graph
+  where
+    ast :: Token
+    ast = stringToAst scriptString
+
+    cfgResult :: CFGResult
+    cfgResult = astToCfgResult ast
+
+    graph :: CFGraph
+    graph = cfGraph cfgResult
+
+    idToToken :: M.Map Id Token
+    idToToken = M.fromList $ execWriter $ doAnalysis (\c -> tell [(getId c, c)]) ast
+
+    idToNode :: M.Map Id (Node, Node)
+    idToNode = cfIdToRange cfgResult
+
+    nodeToStartIds :: M.Map Node (S.Set Id)
+    nodeToStartIds =
+        M.fromListWith S.union $
+            map (\(id, (start, _)) -> (start, S.singleton id)) $
+                M.toList idToNode
+
+    nodeToEndIds :: M.Map Node (S.Set Id)
+    nodeToEndIds =
+        M.fromListWith S.union $
+            map (\(id, (_, end)) -> (end, S.singleton id)) $
+                M.toList idToNode
+
+    formatId :: Id -> String
+    formatId id = fromMaybe ("Unknown " ++ show id) $ do
+        (OuterToken _ token) <- M.lookup id idToToken
+        firstWord <- words (show token) !!! 0
+        -- Strip off "Inner_"
+        (_ : tokenName) <- return $ dropWhile (/= '_') firstWord
+        return $ tokenName ++ " " ++ show id
+
+    formatGroup :: S.Set Id -> String
+    formatGroup set = intercalate ", " $ map formatId $ S.toList set
+
+    nodeLabel (node, label) = unlines [
+        show node ++ ". " ++ show label,
+        "Begin: " ++ formatGroup (M.findWithDefault S.empty node nodeToStartIds),
+        "End: " ++ formatGroup (M.findWithDefault S.empty node nodeToEndIds)
+        ]
+
+
+-- Dump a Control Flow Graph with Data Flow Analysis as GraphViz
+dfaToGraphViz :: CF.CFGAnalysis -> String
+dfaToGraphViz analysis = cfgToGraphVizWith label $ CF.graph analysis
+  where
+    label (node, label) =
+        let
+            desc = show node ++ ". " ++ show label
+        in
+            fromMaybe ("No DFA available\n\n" ++ desc) $ do
+                (pre, post) <- M.lookup node $ CF.nodeToData analysis
+                return $ unlines [
+                    "Precondition: " ++ show pre,
+                    "",
+                    desc,
+                    "",
+                    "Postcondition: " ++ show post
+                    ]
+
+
+-- Dump an Control Flow Graph to GraphViz with a given node formatter
+cfgToGraphVizWith :: (LNode CFNode -> String) -> CFGraph -> String
+cfgToGraphVizWith nodeLabel graph = concat [
+    "digraph {\n",
+    concatMap dumpNode (labNodes graph),
+    concatMap dumpLink (labEdges graph),
+    tagVizEntries graph,
+    "}\n"
+    ]
+  where
+    dumpNode l@(node, label) = show node ++ " [label=" ++ quoteViz (nodeLabel l) ++ "]\n"
+    dumpLink (from, to, typ) = show from ++ " -> " ++ show to ++ " [style=" ++ quoteViz (edgeStyle typ)  ++ "]\n"
+    edgeStyle CFEFlow = "solid"
+    edgeStyle CFEExit = "bold"
+    edgeStyle CFEFalseFlow = "dotted"
+
+quoteViz str = "\"" ++ escapeViz str ++ "\""
+escapeViz [] = []
+escapeViz (c:rest) =
+    case c of
+        '\"' -> '\\' : '\"' : escapeViz rest
+        '\n' -> '\\' : 'l' : escapeViz rest
+        '\\' -> '\\' : '\\' : escapeViz rest
+        _ -> c : escapeViz rest
+
+
+-- Dump an Abstract Syntax Tree (or branch thereof) to GraphViz format
+astToGraphViz :: Token -> String
+astToGraphViz token = concat [
+    "digraph {\n",
+    formatTree token,
+    "}\n"
+    ]
+  where
+    formatTree :: Token -> String
+    formatTree t = snd $ execRWS (doStackAnalysis push pop t) () []
+
+    push :: Token -> RWS () String [Int] ()
+    push (OuterToken (Id n) inner) = do
+        stack <- get
+        put (n : stack)
+        case stack of
+            [] -> return ()
+            (top:_) -> tell $ show top ++ " -> " ++ show n ++ "\n"
+        tell $ show n ++ " [label=" ++ quoteViz (show n ++ ": " ++ take 32 (show inner)) ++ "]\n"
+
+    pop :: Token -> RWS () String [Int] ()
+    pop _ = modify tail
+
+
+-- For each entry point, set the rank so that they'll align in the graph
+tagVizEntries :: CFGraph -> String
+tagVizEntries graph = "{ rank=same " ++ rank ++ " }"
+  where
+    entries = mapMaybe find $ labNodes graph
+    find (node, CFEntryPoint name) = return (node, name)
+    find _ = Nothing
+    rank = unwords $ map (\(c, _) -> show c) entries

src/ShellCheck/Fixer.hs

@@ -22,6 +22,8 @@
 module ShellCheck.Fixer (applyFix, removeTabStops, mapPositions, Ranged(..), runTests) where
 
 import ShellCheck.Interface
+import ShellCheck.Prelude
+import Control.Monad
 import Control.Monad.State
 import Data.Array
 import Data.List
@@ -35,7 +37,7 @@ class Ranged a where
     end     :: a -> Position
     overlap :: a -> a -> Bool
     overlap x y =
-        (yStart >= xStart && yStart < xEnd) || (yStart < xStart && yEnd > xStart)
+        xEnd > yStart && yEnd > xStart
         where
             yStart = start y
             yEnd = end y
@@ -86,6 +88,7 @@ instance Ranged Replacement where
 instance Monoid Fix where
     mempty = newFix
     mappend = (<>)
+    mconcat = foldl mappend mempty -- fold left to right since <> discards right on overlap
 
 instance Semigroup Fix where
     f1 <> f2 =
@@ -200,7 +203,7 @@ doReplace start end o r =
     let si = fromIntegral (start-1)
         ei = fromIntegral (end-1)
         (x, xs) = splitAt si o
-        (y, z) = splitAt (ei - si) xs
+        z = drop (ei - si) xs
     in
     x ++ r ++ z
 
@@ -228,7 +231,7 @@ applyReplacement2 rep string = do
 
     let (l1, l2) = tmap posLine originalPos in
         when (l1 /= 1 || l2 /= 1) $
-            error "ShellCheck internal error, please report: bad cross-line fix"
+            error $ pleaseReport "bad cross-line fix"
 
     let replacer = repString rep
     let shift = (length replacer) - (oldEnd - oldStart)
@@ -273,10 +276,10 @@ getPrefixSum = f 0
   where
     f sum _ PSLeaf = sum
     f sum target (PSBranch pivot left right cumulative) =
-        case () of
-            _ | target < pivot -> f sum target left
-            _ | target > pivot -> f (sum+cumulative) target right
-            _ -> sum+cumulative
+        case target `compare` pivot of
+            LT -> f sum target left
+            GT -> f (sum+cumulative) target right
+            EQ -> sum+cumulative
 
 -- Add a value to the Prefix Sum tree at the given index.
 -- Values accumulate: addPSValue 42 2 . addPSValue 42 3 == addPSValue 42 5
@@ -285,17 +288,17 @@ addPSValue key value tree = if value == 0 then tree else f tree
   where
     f PSLeaf = PSBranch key PSLeaf PSLeaf value
     f (PSBranch pivot left right sum) =
-        case () of
-            _ | key < pivot -> PSBranch pivot (f left) right (sum + value)
-            _ | key > pivot -> PSBranch pivot left (f right) sum
-            _ -> PSBranch pivot left right (sum + value)
+        case key `compare` pivot of
+            LT -> PSBranch pivot (f left) right (sum + value)
+            GT -> PSBranch pivot left (f right) sum
+            EQ -> PSBranch pivot left right (sum + value)
 
 prop_pstreeSumsCorrectly kvs targets =
   let
     -- Trivial O(n * m) implementation
     dumbPrefixSums :: [(Int, Int)] -> [Int] -> [Int]
     dumbPrefixSums kvs targets =
-        let prefixSum target = sum . map snd . filter (\(k,v) -> k <= target) $ kvs
+        let prefixSum target = sum [v | (k,v) <- kvs, k <= target]
         in map prefixSum targets
     -- PSTree O(n * log m) implementation
     smartPrefixSums :: [(Int, Int)] -> [Int] -> [Int]

src/ShellCheck/Formatter/CheckStyle.hs

@@ -24,8 +24,8 @@ import ShellCheck.Formatter.Format
 
 import Data.Char
 import Data.List
-import GHC.Exts
 import System.IO
+import qualified Data.List.NonEmpty as NE
 
 format :: IO Formatter
 format = return Formatter {
@@ -45,12 +45,12 @@ outputResults cr sys =
     else mapM_ outputGroup fileGroups
   where
     comments = crComments cr
-    fileGroups = groupWith sourceFile comments
+    fileGroups = NE.groupWith sourceFile comments
     outputGroup group = do
-        let filename = sourceFile (head group)
-        result <- (siReadFile sys) filename
+        let filename = sourceFile (NE.head group)
+        result <- siReadFile sys (Just True) filename
         let contents = either (const "") id result
-        outputFile filename contents group
+        outputFile filename contents (NE.toList group)
 
 outputFile filename contents warnings = do
     let comments = makeNonVirtual warnings contents

src/ShellCheck/Formatter/Diff.hs

@@ -38,19 +38,17 @@ import System.FilePath
 
 import Test.QuickCheck
 
-import Debug.Trace
-ltt x = trace (show x) x
-
 format :: FormatterOptions -> IO Formatter
 format options = do
-    didOutput <- newIORef False
+    foundIssues <- newIORef False
+    reportedIssues <- newIORef False
     shouldColor <- shouldOutputColor (foColorOption options)
     let color = if shouldColor then colorize else nocolor
     return Formatter {
         header = return (),
-        footer = checkFooter didOutput color,
+        footer = checkFooter foundIssues reportedIssues color,
         onFailure = reportFailure color,
-        onResult  = reportResult didOutput color
+        onResult  = reportResult foundIssues reportedIssues color
     }
 
 
@@ -69,9 +67,10 @@ printErr :: ColorFunc -> String -> IO ()
 printErr color = hPutStrLn stderr . color bold . color red
 reportFailure color file msg = printErr color $ file ++ ": " ++ msg
 
-checkFooter didOutput color = do
-    output <- readIORef didOutput
-    unless output $
+checkFooter foundIssues reportedIssues color = do
+    found <- readIORef foundIssues
+    output <- readIORef reportedIssues
+    when (found && not output) $
             printErr color "Issues were detected, but none were auto-fixable. Use another format to see them."
 
 type ColorFunc = (Int -> String -> String)
@@ -79,19 +78,20 @@ data LFStatus = LinefeedMissing | LinefeedOk
 data DiffDoc a = DiffDoc String LFStatus [DiffRegion a]
 data DiffRegion a = DiffRegion (Int, Int) (Int, Int) [Diff a]
 
-reportResult :: (IORef Bool) -> ColorFunc -> CheckResult -> SystemInterface IO -> IO ()
-reportResult didOutput color result sys = do
+reportResult :: (IORef Bool) -> (IORef Bool) -> ColorFunc -> CheckResult -> SystemInterface IO -> IO ()
+reportResult foundIssues reportedIssues color result sys = do
     let comments = crComments result
+    unless (null comments) $ writeIORef foundIssues True
     let suggestedFixes = mapMaybe pcFix comments
     let fixmap = buildFixMap suggestedFixes
     mapM_ output $ M.toList fixmap
   where
     output (name, fix) = do
-        file <- (siReadFile sys) name
+        file <- siReadFile sys (Just True) name
         case file of
             Right contents -> do
                 putStrLn $ formatDoc color $ makeDiff name contents fix
-                writeIORef didOutput True
+                writeIORef reportedIssues True
             Left msg -> reportFailure color name msg
 
 hasTrailingLinefeed str =
@@ -203,10 +203,9 @@ formatDoc color (DiffDoc name lf regions) =
 buildFixMap :: [Fix] -> M.Map String Fix
 buildFixMap fixes = perFile
   where
-    splitFixes = concatMap splitFixByFile fixes
+    splitFixes = splitFixByFile $ mconcat fixes
     perFile = groupByMap (posFile . repStartPos . head . fixReplacements) splitFixes
 
--- There are currently no multi-file fixes, but let's handle it anyways
 splitFixByFile :: Fix -> [Fix]
 splitFixByFile fix = map makeFix $ groupBy sameFile (fixReplacements fix)
   where

src/ShellCheck/Formatter/Format.hs

@@ -28,6 +28,7 @@ import Data.Array
 import Data.List
 import System.IO
 import System.Info
+import System.Environment
 
 -- A formatter that carries along an arbitrary piece of data
 data Formatter = Formatter {
@@ -68,12 +69,14 @@ makeNonVirtual comments contents =
 
 
 shouldOutputColor :: ColorOption -> IO Bool
-shouldOutputColor colorOption = do
-    term <- hIsTerminalDevice stdout
+shouldOutputColor colorOption =
+    case colorOption of
+        ColorAlways -> return True
+        ColorNever -> return False
+        ColorAuto -> do
+            isTerminal <- hIsTerminalDevice stdout
+            term <- lookupEnv "TERM"
             let windows = "mingw" `isPrefixOf` os
-    let isUsableTty = term && not windows
-    let useColor = case colorOption of
-                       ColorAlways -> True
-                       ColorNever -> False
-                       ColorAuto -> isUsableTty
-    return useColor
+            let dumbTerm = term `elem` [Just "dumb", Just "", Nothing]
+            let isUsableTty = isTerminal && not windows && not dumbTerm
+            return isUsableTty

src/ShellCheck/Formatter/GCC.hs

@@ -23,8 +23,8 @@ import ShellCheck.Interface
 import ShellCheck.Formatter.Format
 
 import Data.List
-import GHC.Exts
 import System.IO
+import qualified Data.List.NonEmpty as NE
 
 format :: IO Formatter
 format = return Formatter {
@@ -39,13 +39,13 @@ outputError file error = hPutStrLn stderr $ file ++ ": " ++ error
 outputAll cr sys = mapM_ f groups
   where
     comments = crComments cr
-    groups = groupWith sourceFile comments
-    f :: [PositionedComment] -> IO ()
+    groups = NE.groupWith sourceFile comments
+    f :: NE.NonEmpty PositionedComment -> IO ()
     f group = do
-        let filename = sourceFile (head group)
-        result <- (siReadFile sys) filename
+        let filename = sourceFile (NE.head group)
+        result <- siReadFile sys (Just True) filename
         let contents = either (const "") id result
-        outputResult filename contents group
+        outputResult filename contents (NE.toList group)
 
 outputResult filename contents warnings = do
     let comments = makeNonVirtual warnings contents

src/ShellCheck/Formatter/JSON.hs

@@ -23,6 +23,7 @@ module ShellCheck.Formatter.JSON (format) where
 import ShellCheck.Interface
 import ShellCheck.Formatter.Format
 
+import Control.DeepSeq
 import Data.Aeson
 import Data.IORef
 import Data.Monoid
@@ -103,7 +104,7 @@ collectResult ref cr sys = mapM_ f groups
     comments = crComments cr
     groups = groupWith sourceFile comments
     f :: [PositionedComment] -> IO ()
-    f group = modifyIORef ref (\x -> comments ++ x)
+    f group = deepseq comments $ modifyIORef ref (\x -> comments ++ x)
 
 finish ref = do
     list <- readIORef ref

src/ShellCheck/Formatter/JSON1.hs

@@ -23,12 +23,13 @@ module ShellCheck.Formatter.JSON1 (format) where
 import ShellCheck.Interface
 import ShellCheck.Formatter.Format
 
+import Control.DeepSeq
 import Data.Aeson
 import Data.IORef
 import Data.Monoid
-import GHC.Exts
 import System.IO
 import qualified Data.ByteString.Lazy.Char8 as BL
+import qualified Data.List.NonEmpty as NE
 
 format :: IO Formatter
 format = do
@@ -113,14 +114,14 @@ outputError file msg = hPutStrLn stderr $ file ++ ": " ++ msg
 collectResult ref cr sys = mapM_ f groups
   where
     comments = crComments cr
-    groups = groupWith sourceFile comments
-    f :: [PositionedComment] -> IO ()
+    groups = NE.groupWith sourceFile comments
+    f :: NE.NonEmpty PositionedComment -> IO ()
     f group = do
-        let filename = sourceFile (head group)
-        result <- siReadFile sys filename
+        let filename = sourceFile (NE.head group)
+        result <- siReadFile sys (Just True) filename
         let contents = either (const "") id result
         let comments' = makeNonVirtual comments contents
-        modifyIORef ref (\x -> comments' ++ x)
+        deepseq comments' $ modifyIORef ref (\x -> comments' ++ x)
 
 finish ref = do
     list <- readIORef ref

src/ShellCheck/Formatter/TTY.hs

@@ -23,6 +23,7 @@ import ShellCheck.Fixer
 import ShellCheck.Interface
 import ShellCheck.Formatter.Format
 
+import Control.DeepSeq
 import Control.Monad
 import Data.Array
 import Data.Foldable
@@ -30,9 +31,9 @@ import Data.Ord
 import Data.IORef
 import Data.List
 import Data.Maybe
-import GHC.Exts
 import System.IO
 import System.Info
+import qualified Data.List.NonEmpty as NE
 
 wikiLink = "https://www.shellcheck.net/wiki/"
 
@@ -88,7 +89,7 @@ rankError err = (ranking, cSeverity $ pcComment err, cCode $ pcComment err)
 appendComments errRef comments max = do
     previous <- readIORef errRef
     let current = map (\x -> (rankError x, cCode $ pcComment x, cMessage $ pcComment x)) comments
-    writeIORef errRef . take max . nubBy equal . sort $ previous ++ current
+    writeIORef errRef $! force . take max . nubBy equal . sort $ previous ++ current
   where
     fst3 (x,_,_) = x
     equal x y = fst3 x == fst3 y
@@ -116,19 +117,19 @@ outputResult options ref result sys = do
     color <- getColorFunc $ foColorOption options
     let comments = crComments result
     appendComments ref comments (fromIntegral $ foWikiLinkCount options)
-    let fileGroups = groupWith sourceFile comments
+    let fileGroups = NE.groupWith sourceFile comments
     mapM_ (outputForFile color sys) fileGroups
 
 outputForFile color sys comments = do
-    let fileName = sourceFile (head comments)
-    result <- (siReadFile sys) fileName
+    let fileName = sourceFile (NE.head comments)
+    result <- siReadFile sys (Just True) fileName
     let contents = either (const "") id result
     let fileLinesList = lines contents
     let lineCount = length fileLinesList
     let fileLines = listArray (1, lineCount) fileLinesList
-    let groups = groupWith lineNo comments
-    mapM_ (\commentsForLine -> do
-        let lineNum = fromIntegral $ lineNo (head commentsForLine)
+    let groups = NE.groupWith lineNo comments
+    forM_ groups $ \commentsForLine -> do
+        let lineNum = fromIntegral $ lineNo (NE.head commentsForLine)
         let line = if lineNum < 1 || lineNum > lineCount
                         then ""
                         else fileLines ! fromIntegral lineNum
@@ -136,10 +137,9 @@ outputForFile color sys comments = do
         putStrLn $ color "message" $
            "In " ++ fileName ++" line " ++ show lineNum ++ ":"
         putStrLn (color "source" line)
-        mapM_ (\c -> putStrLn (color (severityText c) $ cuteIndent c)) commentsForLine
+        forM_ commentsForLine $ \c -> putStrLn $ color (severityText c) $ cuteIndent c
         putStrLn ""
-        showFixedString color commentsForLine (fromIntegral lineNum) fileLines
-      ) groups
+        showFixedString color (toList commentsForLine) (fromIntegral lineNum) fileLines
 
 -- Pick out only the lines necessary to show a fix in action
 sliceFile :: Fix -> Array Int String -> (Fix, Array Int String)
@@ -175,7 +175,7 @@ showFixedString color comments lineNum fileLines =
 cuteIndent :: PositionedComment -> String
 cuteIndent comment =
     replicate (fromIntegral $ colNo comment - 1) ' ' ++
-        makeArrow ++ " " ++ code (codeNo comment) ++ ": " ++ messageText comment
+        makeArrow ++ " " ++ code (codeNo comment) ++ " (" ++ severityText comment ++ "): " ++ messageText comment
   where
     arrow n = '^' : replicate (fromIntegral $ n-2) '-' ++ "^"
     makeArrow =

src/ShellCheck/Interface.hs

@@ -1,5 +1,5 @@
 {-
-    Copyright 2012-2019 Vidar Holen
+    Copyright 2012-2024 Vidar Holen
 
     This file is part of ShellCheck.
     https://www.shellcheck.net
@@ -21,14 +21,14 @@
 module ShellCheck.Interface
     (
     SystemInterface(..)
-    , CheckSpec(csFilename, csScript, csCheckSourced, csIncludedWarnings, csExcludedWarnings, csShellTypeOverride, csMinSeverity, csIgnoreRC, csOptionalChecks)
+    , CheckSpec(csFilename, csScript, csCheckSourced, csIncludedWarnings, csExcludedWarnings, csShellTypeOverride, csMinSeverity, csIgnoreRC, csExtendedAnalysis, csOptionalChecks)
     , CheckResult(crFilename, crComments)
     , ParseSpec(psFilename, psScript, psCheckSourced, psIgnoreRC, psShellTypeOverride)
     , ParseResult(prComments, prTokenPositions, prRoot)
-    , AnalysisSpec(asScript, asShellType, asFallbackShell, asExecutionMode, asCheckSourced, asTokenPositions, asOptionalChecks)
+    , AnalysisSpec(asScript, asShellType, asFallbackShell, asExecutionMode, asCheckSourced, asTokenPositions, asExtendedAnalysis, asOptionalChecks)
     , AnalysisResult(arComments)
     , FormatterOptions(foColorOption, foWikiLinkCount)
-    , Shell(Ksh, Sh, Bash, Dash)
+    , Shell(Ksh, Sh, Bash, Dash, BusyboxSh)
     , ExecutionMode(Executed, Sourced)
     , ErrorMessage
     , Code
@@ -39,11 +39,12 @@ module ShellCheck.Interface
     , ColorOption(ColorAuto, ColorAlways, ColorNever)
     , TokenComment(tcId, tcComment, tcFix)
     , emptyCheckResult
-    , newParseResult
-    , newAnalysisSpec
     , newAnalysisResult
+    , newAnalysisSpec
     , newFormatterOptions
+    , newParseResult
     , newPosition
+    , newSystemInterface
     , newTokenComment
     , mockedSystemInterface
     , mockRcFile
@@ -73,15 +74,19 @@ import qualified Data.Map as Map
 
 
 data SystemInterface m = SystemInterface {
-    -- Read a file by filename, or return an error
-    siReadFile :: String -> m (Either ErrorMessage String),
-    -- Given:
+    -- | Given:
+    --   What annotations say about including external files (if anything)
+    --   A resolved filename from siFindSource
+    --   Read the file or return an error
+    siReadFile :: Maybe Bool -> String -> m (Either ErrorMessage String),
+    -- | Given:
     --   the current script,
+    --   what annotations say about including external files (if anything)
     --   a list of source-path annotations in effect,
     --   and a sourced file,
     --   find the sourced file
-    siFindSource :: String -> [String] -> String -> m FilePath,
-    -- Get the configuration file (name, contents) for a filename
+    siFindSource :: String -> Maybe Bool -> [String] -> String -> m FilePath,
+    -- | Get the configuration file (name, contents) for a filename
     siGetConfig :: String -> m (Maybe (FilePath, String))
 }
 
@@ -95,6 +100,7 @@ data CheckSpec = CheckSpec {
     csIncludedWarnings :: Maybe [Integer],
     csShellTypeOverride :: Maybe Shell,
     csMinSeverity :: Severity,
+    csExtendedAnalysis :: Maybe Bool,
     csOptionalChecks :: [String]
 } deriving (Show, Eq)
 
@@ -119,6 +125,7 @@ emptyCheckSpec = CheckSpec {
     csIncludedWarnings = Nothing,
     csShellTypeOverride = Nothing,
     csMinSeverity = StyleC,
+    csExtendedAnalysis = Nothing,
     csOptionalChecks = []
 }
 
@@ -131,6 +138,14 @@ newParseSpec = ParseSpec {
     psShellTypeOverride = Nothing
 }
 
+newSystemInterface :: Monad m => SystemInterface m
+newSystemInterface =
+    SystemInterface {
+        siReadFile = \_ _ -> return $ Left "Not implemented",
+        siFindSource = \_ _ _ name -> return name,
+        siGetConfig = \_ -> return Nothing
+    }
+
 -- Parser input and output
 data ParseSpec = ParseSpec {
     psFilename :: String,
@@ -161,6 +176,7 @@ data AnalysisSpec = AnalysisSpec {
     asExecutionMode :: ExecutionMode,
     asCheckSourced :: Bool,
     asOptionalChecks :: [String],
+    asExtendedAnalysis :: Maybe Bool,
     asTokenPositions :: Map.Map Id (Position, Position)
 }
 
@@ -171,6 +187,7 @@ newAnalysisSpec token = AnalysisSpec {
     asExecutionMode = Executed,
     asCheckSourced = False,
     asOptionalChecks = [],
+    asExtendedAnalysis = Nothing,
     asTokenPositions = Map.empty
 }
 
@@ -208,7 +225,7 @@ newCheckDescription = CheckDescription {
     }
 
 -- Supporting data types
-data Shell = Ksh | Sh | Bash | Dash deriving (Show, Eq)
+data Shell = Ksh | Sh | Bash | Dash | BusyboxSh deriving (Show, Eq)
 data ExecutionMode = Executed | Sourced deriving (Show, Eq)
 
 type ErrorMessage = String
@@ -256,9 +273,6 @@ data Replacement = Replacement {
 data InsertionPoint = InsertBefore | InsertAfter
     deriving (Show, Eq, Generic, NFData)
 
-instance Ord Replacement where
-    compare r1 r2 = (repStartPos r1) `compare` (repStartPos r2)
-
 newReplacement = Replacement {
     repStartPos = newPosition,
     repEndPos = newPosition,
@@ -310,19 +324,18 @@ data ColorOption =
 
 -- For testing
 mockedSystemInterface :: [(String, String)] -> SystemInterface Identity
-mockedSystemInterface files = SystemInterface {
+mockedSystemInterface files = (newSystemInterface :: SystemInterface Identity) {
     siReadFile = rf,
     siFindSource = fs,
     siGetConfig = const $ return Nothing
 }
   where
-    rf file =
-        case filter ((== file) . fst) files of
-            [] -> return $ Left "File not included in mock."
-            [(_, contents)] -> return $ Right contents
-    fs _ _ file = return file
+    rf _ file = return $
+        case find ((== file) . fst) files of
+            Nothing -> Left "File not included in mock."
+            Just (_, contents) -> Right contents
+    fs _ _ _ file = return file
 
 mockRcFile rcfile mock = mock {
     siGetConfig = const . return $ Just (".shellcheckrc", rcfile)
 }
-

src/ShellCheck/Prelude.hs

@@ -0,0 +1,51 @@
+{-
+    Copyright 2022 Vidar Holen
+
+    This file is part of ShellCheck.
+    https://www.shellcheck.net
+
+    ShellCheck is free software: you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    ShellCheck is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with this program.  If not, see <https://www.gnu.org/licenses/>.
+-}
+
+-- Generic basic utility functions
+module ShellCheck.Prelude where
+
+import Data.Semigroup
+
+
+-- Get element 0 or a default. Like `head` but safe.
+headOrDefault _ (a:_) = a
+headOrDefault def _   = def
+
+-- Get the last element or a default. Like `last` but safe.
+lastOrDefault def [] = def
+lastOrDefault _ list = last list
+
+--- Get element n of a list, or Nothing. Like `!!` but safe.
+(!!!) list i =
+    case drop i list of
+        []    -> Nothing
+        (r:_) -> Just r
+
+
+-- Like mconcat but for Semigroups
+sconcat1 :: (Semigroup t) => [t] -> t
+sconcat1 [x] = x
+sconcat1 (x:xs) = x <> sconcat1 xs
+
+sconcatOrDefault def [] = def
+sconcatOrDefault _ list = sconcat1 list
+
+-- For more actionable "impossible" errors
+pleaseReport str = "ShellCheck internal error, please report: " ++ str

stack.yaml

@@ -2,7 +2,7 @@
 # For more information, see: https://docs.haskellstack.org/en/stable/yaml_configuration/
 
 # Specifies the GHC version and set of packages available (e.g., lts-3.5, nightly-2015-09-21, ghc-7.10.2)
-resolver: lts-13.26
+resolver: lts-18.15
 
 # Local packages, usually specified by relative directory name
 packages:

striptests

@@ -29,6 +29,7 @@ detestify() {
       state = 0;
     }
 
+    /STRIP/ { next; }
     /LANGUAGE TemplateHaskell/ { next; }
     /^import.*Test\./ { next; }
 
@@ -75,4 +76,3 @@ find . -name '.git' -prune -o -type f -name '*.hs' -print |
   do
     modify "$file" detestify
   done
-

test/buildtest

@@ -11,21 +11,37 @@ command -v cabal ||
 
 cabal update ||
   die "can't update"
-cabal install --dependencies-only --enable-tests ||
+
+if [ -e /etc/arch-release ]
+then
+  # Arch has an unconventional packaging setup
+  flags=(--disable-library-vanilla --enable-shared --enable-executable-dynamic --ghc-options=-dynamic)
+else
+  flags=()
+fi
+
+cabal install --dependencies-only --enable-tests "${flags[@]}" ||
+  cabal install --dependencies-only "${flags[@]}" ||
+    cabal install --dependencies-only --max-backjumps -1 "${flags[@]}" ||
       die "can't install dependencies"
-cabal configure --enable-tests ||
+cabal configure --enable-tests "${flags[@]}" ||
   die "configure failed"
 cabal build ||
   die "build failed"
 cabal test ||
   die "test failed"
+cabal haddock ||
+  die "haddock failed"
 
-dist/build/shellcheck/shellcheck - << 'EOF' || die "execution failed"
+sc="$(find . -name shellcheck -type f -perm -111)"
+[ -x "$sc" ] || die "Can't find executable"
+
+"$sc" - << 'EOF' || die "execution failed"
 #!/bin/sh
 echo "Hello World"
 EOF
 
-dist/build/shellcheck/shellcheck - << 'EOF' && die "negative execution failed"
+"$sc" - << 'EOF' && die "negative execution failed"
 #!/bin/sh
 echo $1
 EOF

test/check_release

@@ -1,4 +1,5 @@
 #!/usr/bin/env bash
+# shellcheck disable=SC2257
 
 failed=0
 fail() {
@@ -8,7 +9,18 @@ fail() {
 
 if git diff | grep -q ""
 then
-  fail "There are uncommited changes"
+  fail "There are uncommitted changes"
+fi
+
+version=${current#v}
+if ! grep "Version:" ShellCheck.cabal | grep -qFw "$version"
+then
+  fail "The cabal file does not match tag version $version"
+fi
+
+if ! grep -qF "## $current" CHANGELOG.md
+then
+  fail "CHANGELOG.md does not contain '## $current'"
 fi
 
 current=$(git tag --points-at)
@@ -33,41 +45,38 @@ then
   fail "You are not on master"
 fi
 
-version=${current#v}
-if ! grep "Version:" ShellCheck.cabal | grep -qFw "$version"
-then
-  fail "The cabal file does not match tag version $version"
-fi
-
-if ! grep -qF "## $current" CHANGELOG.md
-then
-  fail "CHANGELOG.md does not contain '## $current'"
-fi
-
 if [[ $(git log -1 --pretty=%B) != "Stable version "* ]]
 then
   fail "Expected git log message to be 'Stable version ...'"
 fi
 
+if [[ $(git log -1 --pretty=%B) != *"CHANGELOG"* ]]
+then
+  fail "Expected git log message to contain CHANGELOG"
+fi
+
 i=1 j=1
 cat << EOF
 
 Manual Checklist
 
 $((i++)). Make sure none of the automated checks above failed
-$((i++)). Make sure Travis build currently passes: https://travis-ci.org/koalaman/shellcheck
-$((i++)). Make sure SnapCraft build currently works: https://build.snapcraft.io/user/koalaman
+$((i++)). Run \`build/build_builder build/*/\` to update all builder images.
+$((j++)). \`build/run_builder dist-newstyle/sdist/ShellCheck-*.tar.gz build/*/\` to verify that they work.
+$((j++)). \`for f in \$(cat build/*/tag); do docker push "\$f"; done\` to upload them.
 $((i++)). Run test/distrotest to ensure that most distros can build OOTB.
+$((i++)). Make sure GitHub Build currently passes: https://github.com/koalaman/shellcheck/actions
+$((i++)). Make sure SnapCraft build currently works: https://build.snapcraft.io/user/koalaman
 $((i++)). Format and read over the manual for bad formatting and outdated info.
-$((i++)). Make sure the Hackage package builds, so that all files are 
+$((i++)). Make sure the Hackage package builds locally.
 
 Release Steps
 
 $((j++)). \`cabal sdist\` to generate a Hackage package
 $((j++)). \`git push --follow-tags\` to push commit
-$((j++)). Wait for Travis to build
+$((j++)). Wait for GitHub Actions to build.
 $((j++)). Verify release:
-  a. Check that the new versions are uploaded: https://shellcheck.storage.googleapis.com/index.html
+  a. Check that the new versions are uploaded: https://github.com/koalaman/shellcheck/tags
   b. Check that the docker images have version tags: https://hub.docker.com/u/koalaman
 $((j++)). If no disaster, upload to Hackage: http://hackage.haskell.org/upload
 $((j++)). Push a new commit that updates CHANGELOG.md

test/distrotest

@@ -17,13 +17,20 @@ and is still highly experimental.
 Make sure you're plugged in and have screen/tmux in place,
 then re-run with $0 --run to continue.
 
-Also note that 'dist' will be deleted.
+Also note that dist*/ and .stack-work/ will be deleted.
 EOF
 exit 0
 }
 
-echo "Deleting 'dist'..."
-rm -rf dist
+echo "Deleting 'dist', 'dist-newstyle', and '.stack-work'..."
+rm -rf dist dist-newstyle .stack-work
+
+execs=$(find . -name shellcheck)
+
+if [ -n "$execs" ]
+then
+  die "Found unexpected executables. Remove and try again: $execs"
+fi
 
 log=$(mktemp) || die "Can't create temp file"
 date >> "$log" || die "Can't write to log"
@@ -61,20 +68,18 @@ done << EOF
 debian:stable         apt-get update && apt-get install -y cabal-install
 debian:testing        apt-get update && apt-get install -y cabal-install
 ubuntu:latest         apt-get update && apt-get install -y cabal-install
-opensuse/leap:latest  zypper install -y cabal-install ghc
-
-# Other Ubuntu versions we want to support
-ubuntu:19.04          apt-get update && apt-get install -y cabal-install
-ubuntu:18.10          apt-get update && apt-get install -y cabal-install
-
-# Misc Haskell including current and latest Stack build
-ubuntu:18.10          set -e; apt-get update && apt-get install -y curl && curl -sSL https://get.haskellstack.org/ | sh -s - -f && cd /mnt && exec test/stacktest
 haskell:latest        true
+opensuse/leap:latest  zypper install -y cabal-install ghc
+fedora:latest         dnf install -y cabal-install ghc-template-haskell-devel findutils libstdc++-static gcc-c++
+archlinux:latest      pacman -S -y --noconfirm cabal-install ghc-static base-devel
 
-# Known to currently fail
-centos:latest         yum install -y epel-release && yum install -y cabal-install
-fedora:latest         dnf install -y cabal-install
-archlinux/base:latest pacman -S -y --noconfirm cabal-install ghc-static base-devel
+# Ubuntu LTS
+ubuntu:24.04          apt-get update && apt-get install -y cabal-install
+ubuntu:22.04          apt-get update && apt-get install -y cabal-install
+ubuntu:20.04          apt-get update && apt-get install -y cabal-install
+
+# Stack on Ubuntu LTS
+ubuntu:24.04          set -e; apt-get update && apt-get install -y curl && curl -sSL https://get.haskellstack.org/ | sh -s - -f && cd /mnt && exec test/stacktest
 EOF
 
 exit "$final"

test/shellcheck.hs

@@ -4,8 +4,12 @@ import Control.Monad
 import System.Exit
 import qualified ShellCheck.Analytics
 import qualified ShellCheck.AnalyzerLib
+import qualified ShellCheck.ASTLib
+import qualified ShellCheck.CFG
+import qualified ShellCheck.CFGAnalysis
 import qualified ShellCheck.Checker
 import qualified ShellCheck.Checks.Commands
+import qualified ShellCheck.Checks.ControlFlow
 import qualified ShellCheck.Checks.Custom
 import qualified ShellCheck.Checks.ShellSupport
 import qualified ShellCheck.Fixer
@@ -14,17 +18,24 @@ import qualified ShellCheck.Parser
 
 main = do
     putStrLn "Running ShellCheck tests..."
-    results <- sequence [
-        ShellCheck.Analytics.runTests
-        ,ShellCheck.AnalyzerLib.runTests
-        ,ShellCheck.Checker.runTests
-        ,ShellCheck.Checks.Commands.runTests
-        ,ShellCheck.Checks.Custom.runTests
-        ,ShellCheck.Checks.ShellSupport.runTests
-        ,ShellCheck.Fixer.runTests
-        ,ShellCheck.Formatter.Diff.runTests
-        ,ShellCheck.Parser.runTests
+    failures <- filter (not . snd) <$> mapM sequenceA tests
+    if null failures then exitSuccess else do
+      putStrLn "Tests failed for the following module(s):"
+      mapM (putStrLn . ("- ShellCheck." ++) . fst) failures
+      exitFailure
+  where
+    tests =
+      [ ("Analytics"          , ShellCheck.Analytics.runTests)
+      , ("AnalyzerLib"        , ShellCheck.AnalyzerLib.runTests)
+      , ("ASTLib"             , ShellCheck.ASTLib.runTests)
+      , ("CFG"                , ShellCheck.CFG.runTests)
+      , ("CFGAnalysis"        , ShellCheck.CFGAnalysis.runTests)
+      , ("Checker"            , ShellCheck.Checker.runTests)
+      , ("Checks.Commands"    , ShellCheck.Checks.Commands.runTests)
+      , ("Checks.ControlFlow" , ShellCheck.Checks.ControlFlow.runTests)
+      , ("Checks.Custom"      , ShellCheck.Checks.Custom.runTests)
+      , ("Checks.ShellSupport", ShellCheck.Checks.ShellSupport.runTests)
+      , ("Fixer"              , ShellCheck.Fixer.runTests)
+      , ("Formatter.Diff"     , ShellCheck.Formatter.Diff.runTests)
+      , ("Parser"             , ShellCheck.Parser.runTests)
       ]
-    if and results
-      then exitSuccess
-      else exitFailure

test/stacktest

@@ -3,7 +3,7 @@
 # various resolvers. It's run via distrotest.
 
 resolvers=(
-  nightly-"$(date -d "3 days ago" +"%Y-%m-%d")"
+#  nightly-"$(date -d "3 days ago" +"%Y-%m-%d")"
 )
 
 die() { echo "$*" >&2; exit 1; }
@@ -15,13 +15,14 @@ die() { echo "$*" >&2; exit 1; }
 command -v stack ||
   die "stack is missing"
 
-stack setup        || die "Failed to setup with default resolver"
+stack setup --allow-different-user || die "Failed to setup with default resolver"
 stack build --test || die "Failed to build/test with default resolver"
 
+# Nice to haves, but not necessary
 for resolver in "${resolvers[@]}"
 do
-  stack --resolver="$resolver" setup        || die "Failed to setup $resolver"
-  stack --resolver="$resolver" build --test || die "Failed build/test with $resolver!"
+  stack --resolver="$resolver" setup        || die "Failed to setup $resolver. This probably doesn't matter."
+  stack --resolver="$resolver" build --test || die "Failed build/test with $resolver! This probably doesn't matter."
 done
 
 echo "Success"