ShellCheck - A shell script static analysis tool

http://www.shellcheck.net

Copyright 2012-2015, Vidar 'koala_man' Holen Licensed under the GNU Affero General Public License, v3

The goals of ShellCheck are:

• To point out and clarify typical beginner's syntax issues, that causes a shell to give cryptic error messages.

• To point out and clarify typical intermediate level semantic problems, that causes 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.

ShellCheck is written in Haskell, and requires 2 GB of memory to compile.

Installing

On systems with Cabal:

cabal update
cabal install shellcheck

On Debian based distros:

apt-get install shellcheck

On OS X with homebrew:

brew install shellcheck

ShellCheck is also available as an online service:

http://www.shellcheck.net

Building with Cabal

This sections describes how to build ShellCheck from a source directory.

First, make sure cabal is installed. On Debian based distros:

apt-get install cabal-install

On Fedora:

yum install cabal-install

On Mac OS X with homebrew (http://brew.sh/):

brew install cabal-install

On Mac OS X with MacPorts (http://www.macports.org/):

port install hs-cabal-install

On native Windows (https://www.haskell.org/platform/):

Download and install the latest version of the Haskell Platform.

Let cabal update itself, in case your distro version is outdated:

$ cabal update
$ cabal install cabal-install

With cabal installed, cd to the ShellCheck source directory and:

$ cabal install

This will install ShellCheck to your ~/.cabal/bin directory.

Add the directory to your PATH (for bash, add this to your ~/.bashrc):

export PATH="$HOME/.cabal/bin:$PATH"

Verify that your PATH is set up correctly:

$ which shellcheck
~/.cabal/bin/shellcheck

On native Windows, the PATH should already be set up, but the system may use a legacy codepage. In cmd.exe, powershell.exe and Powershell ISE, make sure to use a TrueType font, not a Raster font, and set the active codepage to UTF-8 (65001) with chcp:

> chcp 65001
Active code page: 65001

In Powershell ISE, you may need to additionally update the output encoding:

> [Console]::OutputEncoding = [System.Text.Encoding]::UTF8

Running tests

To run the unit test suite:

cabal configure --enable-tests
cabal build
cabal test

Happy ShellChecking!