besu/.github/workflows/parallel-unit-tests.yml

name: parallel-unit-tests
#experimental work in progress - trying to figure out how to split tests across multi-modules by runtime
on:
  workflow_dispatch:

env:
  GRADLE_OPTS: "-Dorg.gradle.daemon=false"
  total-runners: 4
jobs:
  junit:
    runs-on: ubuntu-latest
    strategy:
      fail-fast: false
      matrix:
        runner_index:
          - 0
          - 1
          - 2
          - 3
    steps:
      - name: Checkout Repo
        uses: actions/checkout@v4.1.1
      - name: Split tests
        id: split-tests
        uses: chaosaffe/split-tests@v1-alpha.1
        with:
          glob: '**/src/test/java/**/*.java'
          split-total: ${{ env.total-runners }}
          split-index: ${{ matrix.runner_index }}
          line-count: true
      - name: Set up Java
        uses: actions/setup-java@v4.0.0
        with:
          distribution: adopt
          java-version: 17
          cache: gradle
      - name: write out test list
        run: echo "${{ steps.split-tests.outputs.test-suite }}" >> testList.txt
      - name: debug testfile paths
        run: cat testList.txt
      - name: format gradle args
        # regex means: truncate file paths to align with package name, replacing with tests switch, then drop file extension,
        # then swap path delimiter with package delimiter
        run: cat testList.txt | sed -e 's/[^ ]*src\/test\/java\//--tests\ /g' -e 's/\.java//g' -e 's/\//\./g' >> gradleArgs.txt
      - name: debug test class list
        run: cat gradleArgs.txt
      - name: run unit tests
        run: ./gradlew test `cat gradleArgs.txt`