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datadog

GitHub Action

Run python black code formatter

v2.5 Latest version

Run python black code formatter

datadog

Run python black code formatter

Run the black formatter on your codebase to improve code review experience

Installation

Copy and paste the following snippet into your .yml file.

              
- name: Run python black code formatter

              
  uses: DataDog/[email protected]
Learn more about this action in DataDog/action-py-black-formatter

Choose a version

Action-py-black-formatter GitHub Action

This is a fork of rickstaa/action-black so that we can backport an older version of black working.

Quickstart

In it's simplest form this action can be used to check/format your code using the black formatter.

name: black-action
on: [push, pull_request]
jobs:
  linter_name:
    name: runner / black formatter
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v2
      - uses: datadog/[email protected]
        with:
          check_mode: "true"

Inputs

additional_args

optional: Black additional input arguments. Default "".

only_changed_files

optional: When enabled if you only want to check changed files instead of all files. Recommended for large repositories. Default "false".

main_branch

optional: Default main branch to compare if only_changed_files mode enabled. Default "main".

quiet_mode

optional: (--quiet) Don't emit non-error messages to stderr. Errors are still emitted; silence those with 2>/dev/null. Default "false".

check_mode

optional: (--check) Don't write the files back, just return the status. Return code 0 means nothing would change. Return code 1 means some files would be reformatted. Return code 123 means there was an internal error. Default "false"

print_diff_mode

optional: (--diff) Don't write the files back, just output a diff for each file on stdout. Default "false".

fail_on_error

optional: Exit code when black formatting errors are found [true, false]. Default "true".

Outputs

is_formatted

Boolean specifying whether any files were formatted using the black formatter.

Advanced use cases

Annotate changes

This action can be combined with reviewdog/action-suggester also to annotate any possible changes (uses git diff).

name: black-action
on: [push, pull_request]
jobs:
  linter_name:
    name: runner / black
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v2
      - name: Check files using the black formatter
        uses: datadog/[email protected]
        id: action_black
      - name: Annotate diff changes using reviewdog
        if: steps.action_black.outputs.is_formatted == 'true'
        uses: reviewdog/action-suggester@v1
        with:
          tool_name: blackfmt

Commit changes or create a pull request

This action can be combined with peter-evans/create-pull-request to also apply the annotated changes to the repository.

name: black-action
on: [push, pull_request]
jobs:
  linter_name:
    name: runner / black
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v2
      - name: Check files using the black formatter
        uses: datadog/[email protected]
        id: action_black
      - name: Create Pull Request
        if: steps.action_black.outputs.is_formatted == 'true'
        uses: peter-evans/create-pull-request@v3
        with:
          token: ${{ secrets.GITHUB_TOKEN }}
          title: "Format Python code with psf/black push"
          commit-message: ":art: Format Python code with psf/black"
          body: |
            There appear to be some python formatting errors in ${{ github.sha }}. This pull request
            uses the [psf/black](https://github.com/psf/black) formatter to fix these issues.
          base: ${{ github.head_ref }} # Creates pull request onto pull request or commit branch
          branch: actions/black