Example plumbing for Portage variables

shellcheck.hs

@@ -396,10 +396,12 @@ ioInterface options files = do
     inputs <- mapM normalize files
     cache <- newIORef emptyCache
     configCache <- newIORef ("", Nothing)
+    portageVars <- newIORef Nothing
     return (newSystemInterface :: SystemInterface IO) {
         siReadFile = get cache inputs,
         siFindSource = findSourceFile inputs (sourcePaths options),
-        siGetConfig = getConfig configCache
+        siGetConfig = getConfig configCache,
+        siGetPortageVariables = getOrLoadPortage portageVars
     }
   where
     emptyCache :: Map.Map FilePath String
@@ -523,6 +525,18 @@ ioInterface options files = do
                 ("SCRIPTDIR":rest) -> joinPath (scriptdir:rest)
                 _ -> str
 
+    getOrLoadPortage cache = do
+        x <- readIORef cache
+        case x of
+            Just m -> do
+                hPutStrLn stderr "Reusing previous Portage variables"
+                return m
+            Nothing -> do
+                hPutStrLn stderr "Computing Portage variables"
+                vars <- return $ Map.fromList [("foo", ["bar", "baz"])]  -- TODO: Actually read the variables
+                writeIORef cache $ Just vars
+                return vars
+
 inputFile file = do
     (handle, shouldCache) <-
             if file == "-"

src/ShellCheck/Analytics.hs

@@ -314,7 +314,7 @@ runAndGetComments f s = do
         let pr = pScript s
         root <- prRoot pr
         let spec = defaultSpec pr
-        let params = makeParameters spec
+        let params = runIdentity $ makeParameters (mockedSystemInterface []) spec
         return $
             filterByAnnotation spec params $
                 f params root
@@ -2451,7 +2451,7 @@ checkUnassignedReferences = checkUnassignedReferences' False
 checkUnassignedReferences' includeGlobals params t = warnings
   where
     (readMap, writeMap) = execState (mapM tally $ variableFlow params) (Map.empty, Map.empty)
-    defaultAssigned = Map.fromList $ map (\a -> (a, ())) $ filter (not . null) internalVariables
+    defaultAssigned = Map.fromList $ map (\a -> (a, ())) $ filter (not . null) (internalVariables ++ additionalKnownVariables params)
 
     tally (Assignment (_, _, name, _))  =
         modify (\(read, written) -> (read, Map.insert name () written))

src/ShellCheck/Analyzer.hs

@@ -31,14 +31,14 @@ import qualified ShellCheck.Checks.ShellSupport
 
 
 -- TODO: Clean up the cruft this is layered on
-analyzeScript :: AnalysisSpec -> AnalysisResult
+analyzeScript :: Monad m => SystemInterface m -> AnalysisSpec -> m AnalysisResult
-analyzeScript spec = newAnalysisResult {
+analyzeScript sys spec = do
+    params <- makeParameters sys spec
+    return $ newAnalysisResult {
             arComments =
                 filterByAnnotation spec params . nub $
                     runChecker params (checkers spec params)
-}
+        }
-  where
-    params = makeParameters spec
 
 checkers spec params = mconcat $ map ($ params) [
     ShellCheck.Analytics.checker spec,

src/ShellCheck/AnalyzerLib.hs

@@ -103,7 +103,9 @@ data Parameters = Parameters {
     -- map from token id to start and end position
     tokenPositions     :: Map.Map Id (Position, Position),
     -- Result from Control Flow Graph analysis (including data flow analysis)
-    cfgAnalysis :: CF.CFGAnalysis
+    cfgAnalysis :: CF.CFGAnalysis,
+    -- A set of additional variables known to be set (TODO: make this more general?)
+    additionalKnownVariables :: [String]
     } deriving (Show)
 
 -- TODO: Cache results of common AST ops here
@@ -152,7 +154,7 @@ producesComments c s = do
         let pr = pScript s
         prRoot pr
         let spec = defaultSpec pr
-        let params = makeParameters spec
+        let params = runIdentity $ makeParameters (mockedSystemInterface []) spec
         return . not . null $ filterByAnnotation spec params $ runChecker params c
 
 makeComment :: Severity -> Id -> Code -> String -> TokenComment
@@ -196,11 +198,22 @@ makeCommentWithFix severity id code str fix =
         }
     in force withFix
 
-makeParameters spec = params
+makeParameters :: Monad m => SystemInterface m -> AnalysisSpec -> m Parameters
+makeParameters sys spec = do
+    extraVars <-
+        case shell of
+            Bash -> do -- TODO: EBuild type
+                vars <- siGetPortageVariables sys
+                return $ Map.findWithDefault [] "foo" vars -- TODO: Determine what to look up in map
+            _ -> return []
+    return $ makeParams extraVars
+  where
+    shell = fromMaybe (determineShell (asFallbackShell spec) root) $ asShellType spec
+    makeParams extraVars = params
       where
         params = Parameters {
             rootNode = root,
-        shellType = fromMaybe (determineShell (asFallbackShell spec) root) $ asShellType spec,
+            shellType = shell,
             hasSetE = containsSetE root,
             hasLastpipe =
                 case shellType params of
@@ -225,11 +238,13 @@ makeParameters spec = params
             parentMap = getParentTree root,
             variableFlow = getVariableFlow params root,
             tokenPositions = asTokenPositions spec,
-        cfgAnalysis = CF.analyzeControlFlow cfParams root
+            cfgAnalysis = CF.analyzeControlFlow cfParams root,
+            additionalKnownVariables = extraVars
         }
         cfParams = CF.CFGParameters {
             CF.cfLastpipe = hasLastpipe params,
-        CF.cfPipefail = hasPipefail params
+            CF.cfPipefail = hasPipefail params,
+            CF.cfAdditionalInitialVariables = additionalKnownVariables params
         }
     root = asScript spec
 

src/ShellCheck/CFG.hs

@@ -167,7 +167,9 @@ data CFGParameters = CFGParameters {
     -- Whether the last element in a pipeline runs in the current shell
     cfLastpipe :: Bool,
     -- Whether all elements in a pipeline count towards the exit status
-    cfPipefail :: Bool
+    cfPipefail :: Bool,
+    -- Additional variables to consider defined
+    cfAdditionalInitialVariables :: [String]
 }
 
 data CFGResult = CFGResult {

src/ShellCheck/CFGAnalysis.hs

@@ -197,12 +197,13 @@ unreachableState = modified newInternalState {
 }
 
 -- The default state we assume we get from the environment
-createEnvironmentState :: InternalState
+createEnvironmentState :: CFGParameters -> InternalState
-createEnvironmentState = do
+createEnvironmentState params = do
     foldl' (flip ($)) newInternalState $ concat [
         addVars Data.internalVariables unknownVariableState,
         addVars Data.variablesWithoutSpaces spacelessVariableState,
-        addVars Data.specialIntegerVariables integerVariableState
+        addVars Data.specialIntegerVariables integerVariableState,
+        addVars (cfAdditionalInitialVariables params) unknownVariableState
         ]
   where
     addVars names val = map (\name -> insertGlobal name val) names
@@ -1344,7 +1345,7 @@ analyzeControlFlow params t =
         runST $ f cfg entry exit
   where
     f cfg entry exit = do
-        let env = createEnvironmentState
+        let env = createEnvironmentState params
         ctx <- newCtx $ cfGraph cfg
         -- Do a dataflow analysis starting on the root node
         exitState <- runRoot ctx env entry exit

src/ShellCheck/Checker.hs

@@ -88,11 +88,12 @@ checkScript sys spec = do
                     asTokenPositions = tokenPositions,
                     asOptionalChecks = getEnableDirectives root ++ csOptionalChecks spec
                 } where as = newAnalysisSpec root
-        let analysisMessages =
+        let getAnalysisMessages =
-                maybe []
+                case prRoot result of
-                    (arComments . analyzeScript . analysisSpec)
+                    Just root -> arComments <$> (analyzeScript sys $ analysisSpec root)
-                        $ prRoot result
+                    Nothing -> return []
         let translator = tokenToPosition tokenPositions
+        analysisMessages <- getAnalysisMessages
         return . nub . sortMessages . filter shouldInclude $
             (parseMessages ++ map translator analysisMessages)
 

src/ShellCheck/Debug.hs

@@ -117,7 +117,8 @@ dummySystemInterface = mockedSystemInterface [
 cfgParams :: CFGParameters
 cfgParams = CFGParameters {
     cfLastpipe = False,
-    cfPipefail = False
+    cfPipefail = False,
+    cfAdditionalInitialVariables = []
 }
 
 -- An example script to play with

src/ShellCheck/Interface.hs

@@ -87,7 +87,9 @@ data SystemInterface m = SystemInterface {
     --   find the sourced file
     siFindSource :: String -> Maybe Bool -> [String] -> String -> m FilePath,
     -- | Get the configuration file (name, contents) for a filename
-    siGetConfig :: String -> m (Maybe (FilePath, String))
+    siGetConfig :: String -> m (Maybe (FilePath, String)),
+    -- | Look up Portage Eclass variables
+    siGetPortageVariables :: m (Map.Map String [String])
 }
 
 -- ShellCheck input and output
@@ -141,7 +143,8 @@ newSystemInterface =
     SystemInterface {
         siReadFile = \_ _ -> return $ Left "Not implemented",
         siFindSource = \_ _ _ name -> return name,
-        siGetConfig = \_ -> return Nothing
+        siGetConfig = \_ -> return Nothing,
+        siGetPortageVariables = return Map.empty
     }
 
 -- Parser input and output