ci: coverage (#106)

* ci: update action versions

* ci: add coverage job

* ci: require `CODECOV_TOKEN` secret

* ci: collect coverage for entire workspace

* ci: typo

* ci: dedup

* ci: add concurrency control

.github/workflows/ci.yml

@@ -5,27 +5,30 @@ on:
   pull_request:
 
 env:
+  RUSTFLAGS: -D warnings
   NEXTEST_EXPERIMENTAL_FILTER_EXPR: 1
   CARGO_TERM_COLOR: always
 
+concurrency:
+  group: ${{ github.head_ref || github.run_id }}
+  cancel-in-progress: true
+
 name: ci
 jobs:
   test:
     runs-on: ubuntu-latest
     steps:
       - name: Checkout sources
-        uses: actions/checkout@v2
+        uses: actions/checkout@v3
       - name: Install toolchain
-        uses: actions-rs/toolchain@v1
-        with:
-          toolchain: stable
-          profile: minimal
-          override: true
-      - uses: Swatinem/rust-cache@v1
+        uses: dtolnay/rust-toolchain@stable
+      - uses: Swatinem/rust-cache@v2
         with:
           cache-on-failure: true
+
       - name: Install latest nextest release
         uses: taiki-e/install-action@nextest
+
       - name: Test with latest nextest release
         uses: actions-rs/cargo@v1
         with:
@@ -36,17 +39,12 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Checkout sources
-        uses: actions/checkout@v2
-
+        uses: actions/checkout@v3
       - name: Install toolchain
-        uses: actions-rs/toolchain@v1
+        uses: dtolnay/rust-toolchain@nightly
         with:
-          toolchain: nightly
-          profile: minimal
           components: rustfmt, clippy
-          override: true
-
-      - uses: Swatinem/rust-cache@v1
+      - uses: Swatinem/rust-cache@v2
         with:
           cache-on-failure: true
 
@@ -59,5 +57,30 @@ jobs:
       - name: cargo clippy
         uses: actions-rs/clippy-check@v1
         with:
-          args: --all --all-features -- -D warnings
+          args: --all --all-features
           token: ${{ secrets.GITHUB_TOKEN }}
+
+  coverage:
+    runs-on: ubuntu-latest
+    # nightly rust might break from time to time
+    continue-on-error: true
+    needs: [test]
+    steps:
+      - uses: actions/checkout@v3
+      - uses: dtolnay/rust-toolchain@stable
+        with:
+          components: llvm-tools-preview
+      - uses: Swatinem/rust-cache@v2
+
+      - name: Install latest nextest release
+        uses: taiki-e/install-action@nextest
+      - name: Install cargo-llvm-cov
+        uses: taiki-e/install-action@cargo-llvm-cov
+
+      - name: Collect coverage data
+        run: cargo llvm-cov nextest --lcov --output-path lcov.info --locked --workspace --all-features
+      - name: Upload coverage data to codecov
+        uses: codecov/codecov-action@v3
+        with:
+          token: ${{ secrets.CODECOV_TOKEN }}
+          files: lcov.info