patchcov 0.4.1

Patch coverage for git diffs: attribute lcov, llvm-cov, Cobertura, Go and JaCoCo reports to a diff and gate on it.
Documentation 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178

name: CI

on:
  push:
    branches: [main]
  pull_request:
    branches: [main]
  merge_group:

env:
  CARGO_TERM_COLOR: always

# Every job sets `timeout-minutes`: the default is 6 hours, and a hung test would otherwise hold a
# required check until the merge queue gives up at 60 minutes. The limits are several times the
# slowest run seen over the last 100 runs (113 s, Windows test); the jobs that run tests get 15
# (so does Coverage, which can build twice when it has to recompute a baseline), the build-only
# ones 10.
jobs:
  test:
    name: Test (${{ matrix.os }})
    runs-on: ${{ matrix.os }}
    timeout-minutes: 15
    strategy:
      fail-fast: false
      matrix:
        os: [ubuntu-latest, macos-latest, windows-latest]
    steps:
      - uses: actions/checkout@v7
      - uses: dtolnay/rust-toolchain@stable
      - uses: Swatinem/rust-cache@v2
      - run: cargo test --locked --all-targets
      - run: cargo test --locked --doc

  lint:
    name: Lint
    runs-on: ubuntu-latest
    timeout-minutes: 10
    steps:
      - uses: actions/checkout@v7
      - uses: dtolnay/rust-toolchain@stable
        with:
          components: rustfmt, clippy
      - uses: Swatinem/rust-cache@v2
      - run: cargo fmt --check
      - run: cargo clippy --locked --all-targets -- -D warnings
      - run: cargo run --locked -- lint-markers

  msrv:
    name: MSRV (1.88)
    runs-on: ubuntu-latest
    timeout-minutes: 15
    steps:
      - uses: actions/checkout@v7
      - uses: dtolnay/rust-toolchain@1.88.0
      - uses: Swatinem/rust-cache@v2
      - run: cargo test --locked --all-targets
      - run: cargo test --locked --doc

  docs:
    name: Docs
    runs-on: ubuntu-latest
    timeout-minutes: 10
    env:
      RUSTDOCFLAGS: -D warnings
    steps:
      - uses: actions/checkout@v7
      - uses: dtolnay/rust-toolchain@stable
      - uses: Swatinem/rust-cache@v2
      - run: cargo doc --locked --no-deps --document-private-items

  # patchcov measures its own pull requests with the action it ships. Coverage is required
  # by the main ruleset, so a red PR run blocks a merge. The action installs the Rust toolchain,
  # the cache and cargo-llvm-cov itself. It publishes the baseline on a push to main, from
  # this workflow (the action looks for `ci.yml`), and comments and gates on pull requests.
  # On a merge_group run it would only repeat the instrumented tests, so the job is skipped
  # there; the skipped job satisfies the queue's required check. Only `@v1` is
  # tagged; `v1` defaults to an old patchcov, so `version` asks for the current release.
  coverage:
    name: Coverage
    if: github.event_name != 'merge_group'
    runs-on: ubuntu-latest
    timeout-minutes: 15
    permissions:
      contents: read
      actions: read # find and download the baseline artifact of the merge base's run
      pull-requests: write # post the coverage comment
    steps:
      - uses: actions/checkout@v7
        with:
          fetch-depth: 0 # full history so the merge base resolves
      - uses: action-works/patchcov-action@v1
        with:
          version: latest
          fail-under-patch: 90
          fail-under-lines: 95
          # A fork's token is read-only, so the comment would fail; the gates still apply.
          comment: ${{ github.event.pull_request.head.repo.fork != true }}

  # Exercise the PR's own CLI as well as the released action above. Advisory and PR-only:
  # no baseline recompute or publish, so this report has no deltas/indirect changes.
  coverage-pr-build:
    name: Coverage (PR build)
    if: github.event_name == 'pull_request'
    runs-on: ubuntu-latest
    timeout-minutes: 15
    permissions:
      contents: read
      pull-requests: write
    steps:
      - uses: actions/checkout@v7
        with:
          ref: ${{ github.event.pull_request.head.sha }}
          fetch-depth: 0
      - uses: dtolnay/rust-toolchain@stable
        with:
          components: llvm-tools-preview
      - uses: Swatinem/rust-cache@v2
        with:
          key: coverage-pr-build
      - uses: taiki-e/install-action@cargo-llvm-cov
      - name: Build the PR's patchcov
        run: cargo build --locked --bin patchcov
      - name: Measure the PR head
        run: |
          cargo llvm-cov --locked --all-features --workspace --no-report
          cargo llvm-cov report --lcov --output-path coverage-pr-head.lcov
      - name: Render with the PR's patchcov
        id: diff
        env:
          BASE_SHA: ${{ github.event.pull_request.base.sha }}
          HEAD_SHA: ${{ github.event.pull_request.head.sha }}
          COMMIT_URL: ${{ github.server_url }}/${{ github.repository }}/commit
          RUN_URL: ${{ github.server_url }}/${{ github.repository }}/actions/runs/${{ github.run_id }}
        run: |
          base=$(git merge-base "$BASE_SHA" "$HEAD_SHA")
          echo "base=$base" >> "$GITHUB_OUTPUT"
          ./target/debug/patchcov diff --report coverage-pr-head.lcov \
            --base-ref "$base" --head-ref "$HEAD_SHA" --collapse-ranges \
            --base-sha "$base" --head-sha "$HEAD_SHA" \
            --commit-url "$COMMIT_URL" --run-url "$RUN_URL" > coverage-pr-build.md
          {
            echo '## PR build'
            echo
            echo "Measured and rendered by this PR's own patchcov build. No baseline deltas; see the release Coverage report for those."
            echo
            cat coverage-pr-build.md
          } > coverage-pr-comment.md
      - name: Upload PR-build coverage
        id: coverage-artifact
        uses: actions/upload-artifact@v7
        with:
          name: coverage-pr-build
          if-no-files-found: error
          path: |
            coverage-pr-head.lcov
            coverage-pr-comment.md
      # The archived report has the run link; the upload URL exists only after upload.
      - name: Link PR-build artifact and publish run summary
        env:
          ARTIFACT_URL: ${{ steps.coverage-artifact.outputs.artifact-url }}
        run: |
          printf '\n<sub>📦 [PR-build coverage report (LCOV and Markdown)](%s)</sub>\n' "$ARTIFACT_URL" >> coverage-pr-comment.md
          cat coverage-pr-comment.md >> "$GITHUB_STEP_SUMMARY"
      - name: Comment PR-build coverage
        if: github.event.pull_request.head.repo.fork != true
        uses: marocchino/sticky-pull-request-comment@v3
        with:
          header: coverage-pr-build
          path: coverage-pr-comment.md
      # Render/upload/comment before gating so low coverage still leaves a report.
      - name: Enforce coverage gates with the PR's patchcov
        env:
          BASE_SHA: ${{ steps.diff.outputs.base }}
          HEAD_SHA: ${{ github.event.pull_request.head.sha }}
        run: |
          ./target/debug/patchcov diff --report coverage-pr-head.lcov \
            --base-ref "$BASE_SHA" --head-ref "$HEAD_SHA" \
            --fail-under-patch 90 --fail-under-lines 95 -o json > /dev/null