Affected Package Detection Enterprise

The affected command detects which workspace packages are impacted by git changes and runs commands only on those packages. This dramatically speeds up CI pipelines by skipping unchanged packages.

Usage

# List affected packages
dart run monorepo_toolkit affected list

# Run analysis on affected packages only
dart run monorepo_toolkit affected analyze

# Run tests on affected packages only
dart run monorepo_toolkit affected test --coverage

# Run any command on affected packages
dart run monorepo_toolkit affected run -- "dart format --set-exit-if-changed ."

Subcommands

affected list

Lists packages affected by git changes compared to a base branch:

dart run monorepo_toolkit affected list --base develop
dart run monorepo_toolkit affected list --format plain  # CI-friendly output

Flag	Abbr	Default	Description
--base	-b	main	Base branch or commit to compare against
--format	-f	pretty	Output format: pretty or plain
--json	-j	false	Output as JSON array for GitHub Actions matrix

affected analyze

Runs flutter analyze lib on affected packages:

dart run monorepo_toolkit affected analyze --base develop
dart run monorepo_toolkit affected analyze --no-fail-fast

Flag	Abbr	Default	Description
--base	-b	main	Base branch or commit to compare against
--fail-fast		true	Stop on first package failure

affected test

Runs flutter test on affected packages with optional coverage collection:

dart run monorepo_toolkit affected test --coverage --base develop

Flag	Abbr	Default	Description
--base	-b	main	Base branch or commit to compare against
--coverage		false	Collect coverage information
--fail-fast		true	Stop on first package failure
--total-shards	—	—	Total number of shards for within-package test splitting
--shard-index	—	—	Zero-based index of this shard (requires --total-shards)

affected run

Runs an arbitrary command on affected packages:

dart run monorepo_toolkit affected run -- "flutter test --coverage"
dart run monorepo_toolkit affected run -- "dart format --set-exit-if-changed ."

Flag	Abbr	Default	Description
--base	-b	main	Base branch or commit to compare against
--fail-fast		true	Stop on first package failure

Configuration

Create an affected.yaml at the workspace root:

affected:
  base_branch: develop

  # Predefined commands (merged with defaults: analyze, test, format)
  commands:
    lint: "dart run custom_lints ."

  # Packages always included regardless of changes
  always_include:
    - template_app

  # Glob patterns to ignore when detecting changes
  ignore:
    - "devtools/**"
    - ".github/**"
    - ".claude/**"

The default ignore patterns are devtools/**, .github/**, and .claude/**. The default predefined commands are analyze (flutter analyze lib), test (flutter test), and format (dart format --set-exit-if-changed .).

CI integration

steps:
  - name: Analyze affected packages
    run: dart run monorepo_toolkit affected analyze --base origin/develop

  - name: Test affected packages
    run: dart run monorepo_toolkit affected test --coverage --base origin/develop

GitHub Actions Matrix (CI Parallelism)

Use affected list --json to feed a dynamic matrix into GitHub Actions, so each affected package is tested in its own parallel job.

jobs:
  detect:
    runs-on: ubuntu-latest
    outputs:
      packages: ${{ steps.affected.outputs.packages }}
    steps:
      - uses: actions/checkout@v4
        with:
          fetch-depth: 0
      - uses: dart-lang/setup-dart@v1
      - name: Detect affected packages
        id: affected
        run: |
          PACKAGES=$(dart run monorepo_toolkit affected list --json --base origin/develop)
          echo "packages=$PACKAGES" >> "$GITHUB_OUTPUT"

  test:
    needs: detect
    if: ${{ needs.detect.outputs.packages != '[]' }}
    runs-on: ubuntu-latest
    strategy:
      fail-fast: false
      matrix:
        package: ${{ fromJSON(needs.detect.outputs.packages) }}
    steps:
      - uses: actions/checkout@v4
      - uses: dart-lang/setup-dart@v1
      - name: Test ${{ matrix.package }}
        run: dart run monorepo_toolkit affected test --base origin/develop

The --json flag outputs a JSON array of package names (e.g. ["auth_impl","ui_kit"]). GitHub's fromJSON() function expands this into the matrix, creating one job per affected package automatically. See ci-affected-matrix.yml.example in the generated project's .github/workflows/ directory for the full annotated example.