GitHub Action: Run shellcheck with reviewdog

This action runs shellcheck with reviewdog on pull requests to improve code review experience.

Inputs

`github_token`

Optional. ${{ github.token }} is used by default.

`level`

Optional. Report level for reviewdog [info,warning,error]. It's same as -level flag of reviewdog.

`reporter`

Reporter of reviewdog command [github-pr-check,github-pr-review,github-check]. Default is github-pr-check. github-pr-review can use Markdown and add a link to rule page in reviewdog reports.

`filter_mode`

Optional. Filtering mode for the reviewdog command [added,diff_context,file,nofilter]. Default is file.

`fail_on_error`

Optional. Exit code for reviewdog when errors are found [true,false] Default is false.

`reviewdog_flags`

Optional. Additional reviewdog flags

`path`

Optional. Base directory to run shellcheck. Same as [path] of find command. Default: .

Directories are separated by lines. e.g.:

path: |
  tools
  src

`pattern`

Optional. File patterns of target files. Same as -name [pattern] of find command. Default: *.sh

Patterns are separated by lines. e.g.:

pattern: |
  *.bash
  *.sh

`exclude`

Optional. Exclude patterns of target files. Same as -not -path [exclude] of find command. Default: */.git/*

Patterns are separated by lines. e.g.:

exclude: |
  */.git/*
  ./.cache/*

`check_all_files_with_shebangs`

Optional. Checks all files with shebangs in the repository even if they do not match pattern. Default is false.

`shellcheck_flags`

Optional. Flags of shellcheck command. Default: --external-sources

Example usage

.github/workflows/reviewdog.yml

name: reviewdog
on: [pull_request]
jobs:
  shellcheck:
    name: runner / shellcheck
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4
      - name: shellcheck
        uses: reviewdog/action-shellcheck@v1
        with:
          github_token: ${{ secrets.github_token }}
          reporter: github-pr-review # Change reporter.
          path: "." # Optional.
          pattern: "*.sh" # Optional.
          exclude: "./.git/*" # Optional.
          check_all_files_with_shebangs: "false" # Optional.

Known issue

Running shellcheck.exe on Windows might fail with the following error:

SC1017: Literal carriage return. Run script through tr -d '\r'

This is due to the presence of a carriage return character (\r) in the script.

To fix this, you can simply create or edit the .gitattributes file in the root of your repository with the following contents:

*.sh text eol=lf

This would ensure that the scripts are checked out with the correct line ending.