Switch to gcov/lcov format

.codecov.yml

@@ -7,7 +7,3 @@ coverage:
 
 ignore:
   - "src/test/"
-
-parsers:
-  cobertura:
-    partials_as_hits: true

.github/workflows/nix.yml

@@ -168,6 +168,8 @@ jobs:
         run: |
           mkdir -p ~/.conan
           tar -xzf conan.tar -C ~/.conan
+      - name: install gcovr
+        run: pip install "gcovr>=7,<8"
       - name: check environment
         run: |
           echo ${PATH} | tr ':' '\n'
@@ -191,27 +193,27 @@ jobs:
           configuration: ${{ matrix.configuration }}
           cmake-args: >-
             -Dcoverage=ON
-            -Dcoverage_format=xml
+            -Dcoverage_format=lcov
             -DCODE_COVERAGE_VERBOSE=ON
             -DCMAKE_CXX_FLAGS="-O0"
             -DCMAKE_C_FLAGS="-O0"
           cmake-target: coverage
       - name: build
         shell: bash
         run: |
-          mv "${build_dir}/coverage.xml" ./
+          mv "${build_dir}/coverage.lcov" ./
       - name: archive coverage report
         uses: actions/upload-artifact@v3
         with:
-          name: coverage.xml
-          path: coverage.xml
+          name: coverage.lcov
+          path: coverage.lcov
           retention-days: 30
       - name: upload coverage report
         uses: codecov/codecov-action@v4.1.1
         with:
-          files: coverage.xml
+          files: coverage.lcov
           fail_ci_if_error: true
           disable_search: true
           verbose: true
-          plugin: cobertura
+          plugin: null
           token: ${{ secrets.CODECOV_TOKEN }}