ci: add code coverage integration

.coveragerc

@@ -0,0 +1,2 @@
+[run]
+omit = tests/*

.github/workflows/CI.yml

@@ -108,6 +108,25 @@ jobs:
           path: |
             ${{ github.workspace }}/artifacts
 
+      - name: Test with pytest
+        id: test
+        shell: bash
+        run: |
+          python -m pytest \
+            -rxXs \
+            --tb=native \
+            --verbose \
+            --cov-config=.coveragerc \
+            --cov=pyra \
+            --cov=. \
+            tests
+
+      - name: Upload coverage artifact
+        uses: actions/upload-artifact@v4
+        with:
+          name: coverage-${{ matrix.os }}-${{ matrix.architecture }}
+          path: .coverage
+
       - name: Create/Update GitHub Release
         if: ${{ needs.setup_release.outputs.publish_release == 'true' }}
         uses: LizardByte/create-release-action@v2023.1210.832
@@ -121,3 +140,32 @@ jobs:
           prerelease: true  # ${{ needs.setup_release.outputs.publish_pre_release }}
           tag: ${{ needs.setup_release.outputs.release_tag }}
           token: ${{ secrets.GH_BOT_TOKEN }}
+
+  coverage:
+    name: Process test coverage (${{ matrix.os }}-${{ matrix.architecture }})
+    runs-on: ${{ matrix.os }}
+    needs: build
+    if: always()  # code coverage tracks coverage on all branches
+    strategy:
+      fail-fast: false
+      matrix:
+        os: [windows-2019, ubuntu-20.04, macos-11]
+        architecture: [x64]
+        include:  # additional runs
+          - os: windows-2019
+            architecture: x86
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+
+      - name: Download coverage artifacts
+        uses: actions/download-artifact@v4
+        with:
+          name: coverage-${{ matrix.os }}-${{ matrix.architecture }}
+
+      - name: Upload coverage to Codecov
+        uses: codecov/codecov-action@v3
+        with:
+          fail_ci_if_error: true
+          files: .coverage
+          flags: ${{ runner.os }}-${{ matrix.architecture }}

requirements-dev.txt

@@ -2,4 +2,5 @@
 flake8==6.1.0
 pyinstaller==6.3.0
 pytest==7.4.3
+pytest-cov==4.1.0
 rstcheck[sphinx]==6.2.0