name: GnuTests

# Run the upstream GNU grep testsuite against the Rust grep implementation to
# track and guard byte-for-byte compatibility. See util/run-gnu-testsuite.sh.

on:
  pull_request:
  push:
    branches:
      - '*'

# End the current execution if there is a new changeset in the PR.
concurrency:
  group: ${{ github.workflow }}-${{ github.ref }}
  cancel-in-progress: ${{ github.ref != 'refs/heads/main' }}

env:
  DEFAULT_BRANCH: ${{ github.event.repository.default_branch }}
  TEST_FULL_SUMMARY_FILE: 'grep-gnu-full-result.json'

jobs:
  native:
    name: Run GNU grep testsuite
    runs-on: ubuntu-24.04
    steps:
    - name: Checkout code (grep)
      uses: actions/checkout@v4
      with:
        path: 'grep'
        persist-credentials: false
    - uses: dtolnay/rust-toolchain@master
      with:
        toolchain: stable
    - uses: Swatinem/rust-cache@v2
      with:
        workspaces: "./grep -> target"

    - name: Fetch GNU grep testsuite
      shell: bash
      run: |
        ## Download and extract the upstream GNU grep release tarball
        mkdir -p gnu.grep
        cd gnu.grep
        bash ../grep/util/fetch-gnu.sh

    - name: Build Rust grep binary
      shell: bash
      run: |
        cd 'grep'
        cargo build --release

    - name: Run GNU grep testsuite
      shell: bash
      run: |
        cd 'grep'
        export GNU_GREP_DIR="../gnu.grep"
        ./util/run-gnu-testsuite.sh --json-output "${{ env.TEST_FULL_SUMMARY_FILE }}" || true

    - name: Upload full json results
      uses: actions/upload-artifact@v4
      with:
        name: grep-gnu-full-result
        path: grep/${{ env.TEST_FULL_SUMMARY_FILE }}
        if-no-files-found: warn

  aggregate:
    needs: [native]
    permissions:
      actions: read
      contents: read
      pull-requests: read
    name: Aggregate GNU test results
    runs-on: ubuntu-24.04
    steps:
    - name: Initialize workflow variables
      id: vars
      shell: bash
      run: |
        ## VARs setup
        outputs() { step_id="${{ github.action }}"; for var in "$@" ; do echo steps.${step_id}.outputs.${var}="${!var}"; echo "${var}=${!var}" >> $GITHUB_OUTPUT; done; }
        TEST_SUMMARY_FILE='grep-gnu-result.json'
        outputs TEST_SUMMARY_FILE

    - name: Checkout code (grep)
      uses: actions/checkout@v4
      with:
        path: 'grep'
        persist-credentials: false

    - name: Retrieve reference artifacts
      uses: dawidd6/action-download-artifact@v6
      continue-on-error: true
      with:
        workflow: GnuTests.yml
        branch: "${{ env.DEFAULT_BRANCH }}"
        workflow_conclusion: completed
        path: "reference"
        if_no_artifact_found: warn

    - name: Download full json results
      uses: actions/download-artifact@v4
      with:
        name: grep-gnu-full-result
        path: results

    - name: Extract/summarize testing info
      id: summary
      shell: bash
      run: |
        ## Extract/summarize testing info
        outputs() { step_id="${{ github.action }}"; for var in "$@" ; do echo steps.${step_id}.outputs.${var}="${!var}"; echo "${var}=${!var}" >> $GITHUB_OUTPUT; done; }

        RESULT_FILE="results/${{ env.TEST_FULL_SUMMARY_FILE }}"
        if [[ ! -f "$RESULT_FILE" ]]; then
          echo "::error ::Result file $RESULT_FILE not found"
          find results -type f || true
          exit 1
        fi

        TOTAL=$(jq -r '.summary.total // 0' "$RESULT_FILE")
        PASS=$(jq -r '.summary.passed // 0' "$RESULT_FILE")
        FAIL=$(jq -r '.summary.failed // 0' "$RESULT_FILE")
        SKIP=$(jq -r '.summary.skipped // 0' "$RESULT_FILE")

        output="GNU grep tests summary = TOTAL: $TOTAL / PASS: $PASS / FAIL: $FAIL / SKIP: $SKIP"
        echo "${output}"
        if [[ "$FAIL" -gt 0 ]]; then
          echo "::warning ::${output}"
        fi

        outputs TOTAL PASS FAIL SKIP

    - name: Compare test failures VS reference
      shell: bash
      run: |
        ## Compare current results against the reference summary from the default branch
        REF_SUMMARY_FILE='reference/grep-gnu-full-result/${{ env.TEST_FULL_SUMMARY_FILE }}'
        CURRENT_SUMMARY_FILE="results/${{ env.TEST_FULL_SUMMARY_FILE }}"
        IGNORE_INTERMITTENT="grep/.github/workflows/ignore-intermittent.txt"

        # Set up comment directory for the GnuComment workflow.
        COMMENT_DIR="reference/comment"
        mkdir -p ${COMMENT_DIR}
        echo ${{ github.event.number }} > ${COMMENT_DIR}/NR
        COMMENT_LOG="${COMMENT_DIR}/result.txt"
        : > "${COMMENT_LOG}"

        COMPARISON_RESULT=0
        if test -f "${REF_SUMMARY_FILE}"; then
          python3 grep/util/compare_test_results.py \
            --ignore-file "${IGNORE_INTERMITTENT}" \
            --output "${COMMENT_LOG}" \
            "${CURRENT_SUMMARY_FILE}" "${REF_SUMMARY_FILE}" || COMPARISON_RESULT=$?
        else
          echo "::warning ::Skipping test comparison; no prior reference summary at '${REF_SUMMARY_FILE}'."
        fi

        if [ ${COMPARISON_RESULT} -eq 1 ]; then
          echo "::error ::Found new non-intermittent test failures"
          UPLOAD_EXIT=1
        else
          echo "::notice ::No new test failures detected"
          UPLOAD_EXIT=0
        fi
        echo "UPLOAD_EXIT=${UPLOAD_EXIT}" >> $GITHUB_ENV

    - name: Upload comparison log (for GnuComment workflow)
      if: success() || failure()
      uses: actions/upload-artifact@v4
      with:
        name: comment
        path: reference/comment/

    - name: Report test results
      if: success() || failure()
      shell: bash
      run: |
        echo "::notice ::GNU grep testsuite: TOTAL ${{ steps.summary.outputs.TOTAL }} / PASS ${{ steps.summary.outputs.PASS }} / FAIL ${{ steps.summary.outputs.FAIL }} / SKIP ${{ steps.summary.outputs.SKIP }}"
        # Fail the job if the comparison found new non-intermittent regressions.
        exit "${UPLOAD_EXIT:-0}"