ci: move coverage to own workflow

.github/workflows/ci-post-merge.yml

@@ -103,28 +103,6 @@ jobs:
           cargo install cargo-cache --version 0.6.2 --no-default-features --features ci-autoclean
           cargo-cache
 
-  coverage:
-    name: coverage
-    runs-on: ubuntu-latest
-    steps:
-      - uses: actions/checkout@v3
-
-      - name: Install Rust (nightly)
-        uses: actions-rust-lang/setup-rust-toolchain@v1
-        with: { toolchain: nightly }
-
-      - name: Install cargo-tarpaulin
-        uses: taiki-e/install-action@v1
-        with: { tool: cargo-tarpaulin }
-
-      - name: Generate coverage file
-        if: github.ref == 'refs/heads/master'
-        run: cargo tarpaulin --out Xml --verbose
-      - name: Upload to Codecov
-        if: github.ref == 'refs/heads/master'
-        uses: codecov/codecov-action@v3
-        with: { files: cobertura.xml }
-
   minimal-versions:
     name: minimal versions
     runs-on: ubuntu-latest

.github/workflows/coverage.yml

@@ -0,0 +1,37 @@
+name: Coverage
+
+on:
+  push:
+    branches: [master]
+
+permissions:
+  contents: read
+
+concurrency:
+  group: ${{ github.workflow }}-${{ github.ref }}
+  cancel-in-progress: true
+
+jobs:
+  coverage:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+
+      - name: Install Rust
+        uses: actions-rust-lang/setup-rust-toolchain@v1.5.0
+        with:
+          components: llvm-tools-preview
+
+      - name: Install cargo-llvm-cov
+        uses: taiki-e/install-action@v2.18.9
+        with:
+          tool: cargo-llvm-cov
+
+      - name: Generate code coverage
+        run: cargo llvm-cov --workspace --all-features --codecov --output-path codecov.json
+
+      - name: Upload coverage to Codecov
+        uses: codecov/codecov-action@v3.1.4
+        with:
+          files: codecov.json
+          fail_ci_if_error: true