shellcheck.net

ShellCheck is a GPLv3 tool that analyzes shell scripts, giving warnings and suggestions for bash/sh shell scripts. It aims to point out beginner's syntax issues, intermediate level semantic problems, and subtle caveats, corner cases, and pitfalls that may cause an advanced user's otherwise working script to fail. ShellCheck can be used on the web, through your terminal, in your editor, or in your build or test suites. There are many pre-installed platforms that have ShellCheck available, such as Travis CI, Codacy, Code Climate, and Code Factor. However, ShellCheck can also be installed manually through the system's package manager or by downloading and unpacking a binary release. For customized filtering or reporting, ShellCheck can output simple JSON, CheckStyle compatible XML, and an error dynamic data exchange format. The goal of ShellCheck is to help identify common coding errors, bad practices, and even security vulnerabilities.