name: Code Coverage

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

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

env:
  CARGO_TERM_COLOR: always
  # without matrix_sdk=trace, expressions in `trace!` fields are not evaluated
  # when the `trace!` statement is hit, and thus not covered
  RUST_LOG: info,matrix_sdk=trace

jobs:
  code_coverage:
    name: Code Coverage
    runs-on: "ubuntu-latest"

    # run several docker containers with the same networking stack so the hostname 'synapse'
    # maps to the synapse container, etc.
    services:
      # tests need a synapse: this is a service and not michaelkaye/setup-matrix-synapse@main as the
      # latter does not provide networking for services to communicate with it.
      synapse:
        image: ghcr.io/matrix-org/synapse-service:v1.117.0 # keep in sync with ./ci.yml
        env:
            SYNAPSE_COMPLEMENT_DATABASE: sqlite
            SERVER_NAME: synapse
        ports:
            - 8008:8008

    steps:
      - name: Checkout repository
        uses: actions/checkout@v4
        with:
          ref: ${{ github.event.pull_request.head.sha }}

      - name: Install libsqlite
        run: |
          sudo apt-get update
          sudo apt-get install libsqlite3-dev

      - name: Install Rust
        uses: dtolnay/rust-toolchain@stable

      # Cargo config can screw with caching and is only used for alias config
      # and extra lints, which we don't care about here
      - name: Delete cargo config
        run: rm .cargo/config.toml

      - name: Load cache
        uses: Swatinem/rust-cache@v2
        with:
          save-if: ${{ github.ref == 'refs/heads/main' }}

      - name: Install tarpaulin
        uses: taiki-e/install-action@v2
        with:
          tool: cargo-tarpaulin

      # set up backend for integration tests
      - uses: actions/setup-python@v5
        with:
          python-version: 3.8

      - name: Run tarpaulin
        run: |
          rustup run stable cargo tarpaulin \
            --skip-clean --profile cov --out xml \
            --features experimental-widgets,testing
        env:
          CARGO_PROFILE_COV_INHERITS: 'dev'
          CARGO_PROFILE_COV_DEBUG: 1
          HOMESERVER_URL: "http://localhost:8008"
          HOMESERVER_DOMAIN: "synapse"
          SLIDING_SYNC_PROXY_URL: "http://localhost:8118"

      # Copied with minimal adjustments, source:
      # https://github.com/google/mdbook-i18n-helpers/blob/2168b9cea1f4f76b55426591a9bcc308a620194f/.github/workflows/test.yml
      - name: Get PR number and commit SHA
        run: |
          echo "Storing PR number ${{ github.event.number }}"
          echo "${{ github.event.number }}" > pr_number.txt

          echo "Storing commit SHA ${{ github.event.pull_request.head.sha }}"
          echo "${{ github.event.pull_request.head.sha }}" > commit_sha.txt

      # This stores the coverage report and metadata in artifacts.
      # The actual upload to Codecov is executed by a different workflow `upload_coverage.yml`.
      # The reason for this split is because `on.pull_request` workflows don't have access to secrets.
      - name: Store coverage report in artifacts
        uses: actions/upload-artifact@v4
        with:
          name: codecov_report
          path: |
            cobertura.xml
            pr_number.txt
            commit_sha.txt
          if-no-files-found: error

      - run: |
          echo 'The coverage report was stored in Github artifacts.'
          echo 'It will be uploaded to Codecov using `upload_coverage.yml` workflow shortly.'