References of the form $var and ${var} both map to the same structure in
the AST, which prevents any later analysis functions from distinguishing
them. In preparation for adding checks that need this info, add a Bool
to T_DollarBraced that tracks whether the braces were seen at parsing
time and update all references so that this change is a no-op.
This is motivated by the fact that the popularity of bats is increasing
since the creation of bats-core/bats-core.
The code is a cherry-pick of koalaman/shellcheck/bats branch.
Fixkoalaman/shellcheck#417.
The precedence order that is used to determine the shell
is the following:
1. ShellCheck directive
2. Shebang
3. File extension
A new field `asFallbackShell` has been
added to the record type `AnalysisSpec`.
Pattern matching in "do" requires a MonadFail context, which we don't have in
pure code. Instead, we'll use "case-of" to bind the part of the state that
we're interested in.
It used to only treat all trailing variables in read as varaible
declarings, but an array variable can be declared in other positions:
read -a foo -r
foo is a declared variable, and multiple such variables can be declared.
