A Rust code coverage example using getsentry/codecov-action with GitHub Actions.

This repository demonstrates how to set up code coverage for a Rust project using modern tooling:

• cargo-llvm-cov - LLVM-based coverage instrumentation for Rust
• getsentry/codecov-action - Self-hosted coverage reporting using GitHub Artifacts (no external service or token required)

cargo-llvm-cov has built-in support for Codecov's JSON format via the --codecov flag — it just works:

cargo llvm-cov --codecov --output-path codecov.json

The coverage report is then uploaded using getsentry/codecov-action, which stores results as GitHub Artifacts and compares against the base branch on PRs.

- name: Install Rust toolchain
  uses: dtolnay/rust-toolchain@stable
  with:
    components: llvm-tools

- name: Install cargo-llvm-cov
  uses: taiki-e/install-action@cargo-llvm-cov

- name: Run tests with coverage
  run: cargo llvm-cov --codecov --output-path codecov.json

- name: Upload coverage
  uses: getsentry/codecov-action@main
  with:
    token: ${{ secrets.GITHUB_TOKEN }}
    files: ./codecov.json

Unlike the traditional Codecov service, this action:

• Uses GitHub Artifacts for storage — no external service required
• Only needs GITHUB_TOKEN — no separate Codecov token needed
• Provides PR comments and status checks out of the box
• Supports coverage thresholds and patch coverage enforcement

# Install cargo-llvm-cov
cargo install cargo-llvm-cov

# Run tests with coverage (prints summary to terminal)
cargo llvm-cov

# Generate Codecov JSON report
cargo llvm-cov --codecov --output-path codecov.json

# Or generate LCOV report if preferred
cargo llvm-cov --lcov --output-path lcov.info

• getsentry/codecov-action - The GitHub Action used for coverage
• cargo-llvm-cov - LLVM-based coverage tool for Rust
• codecov/example-rust - Original Codecov Rust example (uses kcov)