CodeCov CI integration

.github/workflows/ci.yml

@@ -82,20 +82,37 @@ jobs:
       - name: Check code for possible improvements
         run: cargo clippy -- -D warnings
 
-      # Prepare the Pull Request Payload artifact. If this fails, we
-      # we fail silently using the `continue-on-error` option. It's
-      # nice if this succeeds, but if it fails for any reason, it
-      # does not mean that our lint-test checks failed.
+  coverage:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+
+      - name: Install Rust stable
+        uses: dtolnay/rust-toolchain@stable
+        with:
+          components: llvm-tools
+
+      - name: Install cargo-llvm-cov
+        uses: taiki-e/install-action@v2
+        with:
+          tool: cargo-llvm-cov
+
+      - name: Generate coverage
+        run: cargo-llvm-cov llvm-cov --lcov --output-path "target/lcov.info" --all-features
+
+      - name: Upload to codecov.io
+        uses: codecov/codecov-action@v3
+        with:
+          token: ${{ secrets.CODECOV_TOKEN }}
+          fail_ci_if_error: true
+
       - name: Prepare Pull Request Payload artifact
         id: prepare-artifact
         if: always() && github.event_name == 'pull_request'
         continue-on-error: true
         run: cat $GITHUB_EVENT_PATH | jq '.pull_request' > pull_request_payload.json
 
-      # This only makes sense if the previous step succeeded. To
-      # get the original outcome of the previous step before the
-      # `continue-on-error` conclusion is applied, we use the
-      # `.outcome` value. This step also fails silently.
       - name: Upload a Build Artifact
         if: always() && steps.prepare-artifact.outcome == 'success'
         continue-on-error: true