Duplicated jobs without matrix strategy

Rule ID	no_matrix_strategy
Category	performance
Severity	low

Multiple nearly-identical jobs differ only in a parameter (OS, Node version, etc.) but do not use a matrix strategy.

Detection

heuristic — Structural comparison across multiple jobs or steps.

Examples

Non-compliant:

jobs:
  test-node-18:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/setup-node@v4
        with: {node-version: 18}
      - run: npm test
  test-node-20:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/setup-node@v4
        with: {node-version: 20}
      - run: npm test
  test-node-22:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/setup-node@v4
        with: {node-version: 22}
      - run: npm test

Compliant:

jobs:
  test:
    runs-on: ubuntu-latest
    strategy:
      matrix:
        node-version: [18, 20, 22]
    steps:
      - uses: actions/setup-node@v4
        with:
          node-version: ${{ matrix.node-version }}
      - run: npm test

Fix: Replace duplicate jobs with a single job using strategy.matrix to iterate over the varying parameter.