name: Coverage

# Non-blocking code coverage for the Rust workspace (primarily iroh-http-core),
# measured with cargo-llvm-cov. Phase 1: this is a baseline report only — it is a
# standalone workflow (not part of the required `CI` checks) and every coverage
# step is `continue-on-error: true`, so it can never fail a pull request or block
# a merge. The report is printed to the job summary and uploaded as a workflow
# artifact (lcov + text summary). No third-party upload integrations or secrets.

on:
  push:
    branches: [main]
    paths-ignore:
      - 'docs/**'
      - '**.md'
      - '.github/ISSUE_TEMPLATE/**'
      - '.agents/skills/**'
      - '.vscode/**'
      - 'CHANGELOG.md'
      - 'CONTRIBUTING.md'
      - 'SECURITY.md'
      - 'LICENSE*'
  pull_request:
    branches: [main]
    paths-ignore:
      - 'docs/**'
      - '**.md'
      - '.github/ISSUE_TEMPLATE/**'
      - '.agents/skills/**'
      - '.vscode/**'
      - 'CHANGELOG.md'
      - 'CONTRIBUTING.md'
      - 'SECURITY.md'
      - 'LICENSE*'
  workflow_dispatch:

permissions:
  contents: read

concurrency:
  group: coverage-${{ github.workflow }}-${{ github.ref }}
  cancel-in-progress: true

env:
  CARGO_TERM_COLOR: always
  CARGO_INCREMENTAL: 0

jobs:
  # ── Baseline Rust coverage — non-blocking (never a required check) ────────────
  coverage:
    name: Rust coverage (llvm-cov)
    runs-on: ubuntu-latest
    # Belt-and-braces: even if a coverage step errors, the job is reported as a
    # success so it never gates a PR while we establish a baseline in phase 1.
    continue-on-error: true
    steps:
      - uses: actions/checkout@v6

      - uses: dtolnay/rust-toolchain@stable
        with:
          components: llvm-tools-preview
      - uses: Swatinem/rust-cache@v2

      - uses: taiki-e/install-action@v2
        with:
          tool: cargo-llvm-cov

      - name: cargo llvm-cov (lcov + summary)
        continue-on-error: true
        run: |
          # Generate an lcov report for external tooling and a human-readable
          # summary for the job log. Scoped to the workspace crates
          # (iroh-http-core, iroh-http-discovery, …); the Tauri crate keeps its
          # own out-of-workspace Cargo.lock and is not included here.
          cargo llvm-cov --workspace --lcov --output-path lcov.info
          cargo llvm-cov --workspace --summary-only | tee coverage-summary.txt

      - name: Publish coverage summary to job summary
        if: always()
        continue-on-error: true
        run: |
          {
            echo '## Rust coverage (cargo-llvm-cov)'
            echo ''
            echo 'Non-blocking baseline report — see the `coverage-report` artifact for the full lcov data.'
            echo ''
            echo '```'
            cat coverage-summary.txt 2>/dev/null || echo 'No coverage summary was produced.'
            echo '```'
          } >> "$GITHUB_STEP_SUMMARY"

      - name: Upload coverage report
        if: always()
        continue-on-error: true
        uses: actions/upload-artifact@v7
        with:
          name: coverage-report
          path: |
            lcov.info
            coverage-summary.txt
          retention-days: 30
          if-no-files-found: warn