haskell-ShellCheck - shell script analysis tool

The goals of ShellCheck are:

* To point out and clarify typical beginner's syntax issues, that cause
  a shell to give cryptic error messages.
* To point out and clarify typical intermediate level semantic
  problems, that cause a shell to behave strangely and
  counter-intuitively.
* To point out subtle caveats, corner cases and pitfalls, that may
  cause an advanced user's otherwise working script to fail under
  future circumstances.