Lefthook Evil Martians

Why Lefthook

• Parallel execution

Gives you more speed. docs

pre-push:
  parallel: true

• Flexible list of files

If you want your own list. Custom and prebuilt examples.

pre-commit:
  jobs:
    - name: lint frontend
      run: yarn eslint {staged_files}

    - name: lint backend
      run: bundle exec rubocop --force-exclusion {all_files}

    - name: stylelint frontend
      files: git diff --name-only HEAD @{push}
      run: yarn stylelint {files}

• Glob and regexp filters

If you want to filter list of files. You could find more glob pattern examples here.

pre-commit:
  jobs:
    - name: lint backend
      glob: "*.rb" # glob filter
      exclude: '(^|/)(application|routes)\.rb$' # regexp filter
      run: bundle exec rubocop --force-exclusion {all_files}

• Execute in sub-directory

If you want to execute the commands in a relative path

pre-commit:
  jobs:
    - name: lint backend
      root: "api/" # Careful to have only trailing slash
      glob: "*.rb" # glob filter
      run: bundle exec rubocop {all_files}

• Run scripts

If oneline commands are not enough, you can execute files. docs

commit-msg:
  jobs:
    - script: "template_checker"
      runner: bash

• Tags

If you want to control a group of commands. docs

pre-push:
  jobs:
    - name: audit packages
      tags:
        - frontend
        - linters
      run: yarn lint

    - name: audit gems
      tags:
        - backend
        - security
      run: bundle audit

• Support Docker

If you are in the Docker environment. docs

pre-commit:
  jobs:
    - script: "good_job.js"
      runner: docker run -it --rm  {cmd}

• Local config

If you are a frontend/backend developer and want to skip unnecessary commands or override something in Docker. docs

# lefthook-local.yml
pre-push:
  exclude_tags:
    - frontend
  jobs:
    - name: audit packages
      skip: true

• Direct control

If you want to run hooks group directly.

$ lefthook run pre-commit

• Your own tasks

If you want to run specific group of commands directly.

fixer:
  jobs:
    - run: bundle exec rubocop --force-exclusion --safe-auto-correct {staged_files}
    - run: yarn eslint --fix {staged_files}

$ lefthook run fixer

• Control output

You can control what lefthook prints with output option.

output:
  - execution
  - failure

Guides

• Install with Node.js
• Install with Ruby
• Install with Homebrew
• Install with Winget
• Install for Debian-based Linux
• Install for RPM-based Linux
• Install for Arch Linux
• Install for Alpine Linux
• Usage
• Configuration

Examples

Check examples

Articles

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• Lefthook for React/React Native apps