Code coverage test version

.github/actions-rs/grcov.yml

@@ -0,0 +1,2 @@
+branch: true
+output-type: coveralls+

.github/workflows/ci.yml

@@ -81,3 +81,54 @@ jobs:
         with:
           command: fmt
           args: --all -- --check
+
+  code_coverage:
+    runs-on: ${{ matrix.os }}
+    needs: ci
+    strategy:
+      matrix:
+        os:
+          - ubuntu-latest
+          - macOS-latest
+          - windows-latest
+        toolchain:
+          - nightly
+
+    steps:
+      - uses: actions/checkout@v1
+
+      - name: Install toolchain
+        uses: actions-rs/toolchain@v1
+        with:
+          toolchain: ${{ matrix.toolchain }}
+          override: true
+
+      - name: Execute tests
+        uses: actions-rs/cargo@v1
+        with:
+          command: test
+          args: --all --all-features
+        env:
+          CARGO_INCREMENTAL: 0
+          RUSTFLAGS: "-Zprofile -Ccodegen-units=1 -Cinline-threshold=0 -Clink-dead-code -Coverflow-checks=off -Zno-landing-pads"
+
+      - name: Gather coverage data
+        id: coverage
+        uses: actions-rs/grcov@dev
+
+      - name: Coveralls upload
+        uses: coverallsapp/github-action@master
+        with:
+          github-token: ${{ secrets.GITHUB_TOKEN }}
+          parallel: true
+          path-to-lcov: ${{ steps.coverage.outputs.report }}
+
+  code_coverage_finalize:
+    runs-on: ubuntu-latest
+    needs: code_coverage
+    steps:
+      - name: Coveralls finalization
+        uses: coverallsapp/github-action@master
+        with:
+          github-token: ${{ secrets.GITHUB_TOKEN }}
+          parallel-finished: true