feat: enable code coverage

Author: brianheineman

.github/workflows/build.yml

@@ -1,11 +1,5 @@
 name: Build & Test
 
-env:
-  CARGO_TERM_COLOR: always
-  RUSTFLAGS: "-D warnings"
-  RUST_LOG: "info"
-  RUST_LOG_SPAN_EVENTS: full
-
 on:
   workflow_call:
     inputs:
@@ -45,13 +39,47 @@ jobs:
     - name: Install Rust
       uses: dtolnay/rust-toolchain@master
       with:
+        components: 'llvm-tools-preview'
         toolchain: stable
 
+    - name: Install grcov
+      uses: taiki-e/install-action@main
+      with:
+        tool: grcov
+
     - name: Enable caching
       uses: Swatinem/rust-cache@v2
 
     - name: Tests
       env:
+        CARGO_TERM_COLOR: always
         GITHUB_TOKEN: ${{secrets.GITHUB_TOKEN}}
+        LLVM_PROFILE_FILE: postgresql-%p-%m.profraw
+        RUST_LOG: "info"
+        RUST_LOG_SPAN_EVENTS: full
+        RUSTFLAGS: -Cinstrument-coverage
+        RUSTDOCFLAGS: -Cinstrument-coverage
       run: |
         cargo test --workspace --all-features
+
+    - name: Produce coverage info
+      if: ${{ startsWith(matrix.os, 'ubuntu-') }}
+      run: |
+        grcov $(find . -name "postgresql-*.profraw" -print) \
+          -s . \
+          --branch \
+          --ignore-not-existing \
+          --ignore='target/*' \
+          --ignore='benches/*' \
+          --ignore='/*' \
+          --binary-path ./target/debug/ \
+          --excl-line='#\[derive' \
+          -t lcov \
+          -o lcov.info
+
+    - name: Upload to codecov.io
+      if: ${{ startsWith(matrix.os, 'ubuntu-') }}
+      uses: codecov/codecov-action@v3
+      with:
+        files: lcov.info
+        fail_ci_if_error: true