coverage.yml

name: Test Coverage

# Run on every push to the main branches and on every pull-request targeting them.
# Also triggers manually from the Actions UI (workflow_dispatch).
on:
  push:
    branches: [main, master, "chore/**", "ci/**", "feature/**"]
  pull_request:
    branches: [main, master]
  workflow_dispatch:

jobs:
  coverage:
    name: "Cargo Test Coverage (≥ 95 %)"
    runs-on: ubuntu-latest

    steps:
      # -----------------------------------------------------------------------
      # 1. Source
      # -----------------------------------------------------------------------
      - name: Checkout repository
        uses: actions/checkout@v4

      # -----------------------------------------------------------------------
      # 2. Rust toolchain — stable is sufficient for Soroban unit tests
      # -----------------------------------------------------------------------
      - name: Install Rust stable toolchain
        uses: dtolnay/rust-toolchain@stable

      # -----------------------------------------------------------------------
      # 3. Cache — speeds up subsequent runs considerably
      # -----------------------------------------------------------------------
      - name: Cache Cargo registry and build artefacts
        uses: actions/cache@v4
        with:
          path: |
            ~/.cargo/registry
            ~/.cargo/git
            target/
          # Key rotates when Cargo.lock changes; falls back to any prior entry.
          key: ${{ runner.os }}-cargo-tarpaulin-${{ hashFiles('**/Cargo.lock') }}
          restore-keys: |
            ${{ runner.os }}-cargo-tarpaulin-
            ${{ runner.os }}-cargo-

      # -----------------------------------------------------------------------
      # 4. Install cargo-tarpaulin via the taiki-e installer — faster than
      #    `cargo install` because it downloads a pre-built binary.
      # -----------------------------------------------------------------------
      - name: Install cargo-tarpaulin
        uses: taiki-e/install-action@v2
        with:
          tool: cargo-tarpaulin

      # -----------------------------------------------------------------------
      # 5. Run coverage
      #    Configuration lives in tarpaulin.toml (workspace root).
      #    A non-zero exit here means coverage fell below the 95 % threshold —
      #    this deliberately fails the workflow.
      # -----------------------------------------------------------------------
      - name: Run test coverage
        run: cargo tarpaulin --config tarpaulin.toml

      # -----------------------------------------------------------------------
      # 6. Upload HTML + XML report as a downloadable workflow artefact.
      #    Always runs so the report is available even when coverage fails.
      # -----------------------------------------------------------------------
      - name: Upload coverage report artefact
        if: always()
        uses: actions/upload-artifact@v4
        with:
          name: coverage-report
          path: coverage/
          retention-days: 30