chore(ci): Add Rust Unit Test code coverage

.github/workflows/rust.yml

@@ -12,9 +12,34 @@ env:
 jobs:
   build:
     runs-on: ubuntu-latest
+    env:
+      CARGO_INCREMENTAL: 0
+      RUSTFLAGS: -C instrument-coverage
+      LLVM_PROFILE_FILE: /tmp/nvmetcfg-%p-%8m.profraw
+
     steps:
     - uses: actions/checkout@v3
+    - uses: dtolnay/rust-toolchain@nightly
+      with:
+        components: llvm-tools-preview
+
     - name: Build
       run: cargo build --verbose
     - name: Run tests
       run: cargo test --verbose
+
+    - name: Merge profile data and export LCOV
+      run: |
+        PATH="$(rustc --print sysroot)/lib/rustlib/x86_64-unknown-linux-gnu/bin:$PATH"
+        llvm-cov --version
+        llvm-profdata merge --sparse -o /tmp/nvmetcfg.profdata /tmp/nvmetcfg-*.profraw
+        llvm-cov export -format=lcov -instr-profile=/tmp/nvmetcfg.profdata \
+          --ignore-filename-regex='/.cargo/registry' \
+          --show-instantiation-summary \
+          $(cargo test --tests --no-run --message-format=json | jq -r "select(.profile.test == true) | .filenames[]" | xargs -I {} printf "-object {} ") > nvmetcfg.lcov
+    - name: Upload to codecov.io
+      uses: codecov/codecov-action@v4
+      with:
+        token: ${{ secrets.CODECOV_TOKEN }}
+        fail_ci_if_error: true
+        files: nvmetcfg.lcov

flake.nix

@@ -33,7 +33,13 @@
           default = nvmetcfg;
         };
         devShells.default = pkgs.mkShell {
-          buildInputs = with pkgs; [rust-bin.stable.latest.default cargo-bloat];
+          buildInputs = with pkgs; [
+            (rust-bin.stable.latest.default.override {
+              extensions = [ "llvm-tools-preview" ];
+            })
+            cargo-bloat
+            cargo-llvm-cov
+          ];
         };
 
         checks = {