Use yet another approach for coverage

.github/workflows/coverage.yml

@@ -1,35 +1,59 @@
-name: coverage
-on: [push, pull_request]
 
+on:
+  push:
+    branches:
+      - main
+  pull_request:
+    branches:
+      - main
+
+name: Code Coverage
 jobs:
   coverage:
+    name: Run test coverage
     runs-on: ubuntu-latest
     steps:
+      - uses: actions/checkout@v1
+
+      - name: Cache cargo registry
+        uses: actions/cache@v1
+        with:
+          path: ~/.cargo/registry
+          key: ${{ runner.os }}-cargo-registry-${{ hashFiles('**/Cargo.lock') }}
+
+      - name: Cache cargo index
+        uses: actions/cache@v1
+        with:
+          path: ~/.cargo/git
+          key: ${{ runner.os }}-cargo-index-${{ hashFiles('**/Cargo.lock') }}
+
+      - name: Cache cargo binaries
+        uses: actions/cache@v1
+        with:
+          path: ~/.cargo/bin
+          key: ${{ runner.os }}-cargo-bin-${{ hashFiles('**/Cargo.lock') }}
+
+      - name: Toolchain setup
+        uses: actions-rs/toolchain@v1
+        with:
+          toolchain: nightly
+          override: true
+          components: llvm-tools-preview
+
+      - name: Install grcov
+        run: if [[ ! -e ~/.cargo/bin/grcov ]]; then cargo install grcov; fi
+
+      - name: Run tests
+        run: cargo test
+        env:
+          RUSTFLAGS: '-Zinstrument-coverage'
+          LLVM_PROFILE_FILE: 'report-%p-%m.profraw'
+
+      - name: Run grcov
+        run: grcov . --binary-path target/debug/deps/ -s . -t lcov --branch --ignore-not-existing --ignore '../**' --ignore '/*' --ignore 'target/*' -o coverage.lcov
 
-    - uses: actions/checkout@v2
-      with:
-        fetch-depth: 0
-
-    - uses: actions-rs/toolchain@v1
-      with:
-        profile: minimal
-        toolchain: nightly
-        override: true
-
-    - uses: actions-rs/cargo@v1
-      with:
-        command: test
-        args: --no-default-features --no-fail-fast
-      env:
-        CARGO_INCREMENTAL: '0'
-        RUSTFLAGS: '-Zprofile -Ccodegen-units=1 -Cinline-threshold=0 -Clink-dead-code -Coverflow-checks=off -Cpanic=abort -Zpanic_abort_tests'
-        RUSTDOCFLAGS: '-Zprofile -Ccodegen-units=1 -Cinline-threshold=0 -Clink-dead-code -Coverflow-checks=off -Cpanic=abort -Zpanic_abort_tests'
-
-
-    - uses: actions-rs/grcov@v0.1
-
-    - name: Push grcov results to Coveralls via GitHub Action
-      uses: coverallsapp/github-action@master
-      with:
-        github-token: ${{ secrets.GITHUB_TOKEN }}
-        path-to-lcov: "./lcov.info"
+      - name: Coveralls upload
+        uses: coverallsapp/github-action@master
+        with:
+          github-token: ${{ secrets.GITHUB_TOKEN }}
+          path-to-lcov: coverage.lcov