✨ Template | CI: add coverage (none/basic/codecov)

mbercx · mbercx · commit 25d02357edb3 · 2026-04-11T20:44:00.000+02:00
Generated packages can now optionally include test coverage measurement and CI
enforcement. A new `coverage` Copier question offers three tiers: `none` (default,
preserving current behavior), `basic` (50% minimum threshold with GitHub Actions job
summary), and `codecov` (Codecov upload with a `.codecov.yml` that prevents coverage
regression).

The CI workflow is converted from static YAML to a Jinja template (`ci.yaml.jinja`) so
the test step can be conditionalized. Coverage config (`[tool.coverage.run]`,
`[tool.coverage.report]`) is added to the generated `pyproject.toml` for the `basic` and
`codecov` tiers.

Also adds `hatch run test-cov` to the template repo for local coverage verification, and
updates feature lists and developer docs to reflect the new capability.
diff --git a/README.md b/README.md
@@ -8,9 +8,10 @@ Template for Python packages based on [`copier`](https://copier.readthedocs.io/e
 
 * 📦 **Package management**:
     - Develop with your preferred tools (extras, [`uv`](https://docs.astral.sh/uv/) or [Hatch](https://hatch.pypa.io/)).
+    - Bespoke dev tooling for generating CHANGELOGs automatically based on emoji-typed commit messages.
     - Build your package with [Hatch](https://hatch.pypa.io/). 
 * 🧹 [**Pre-commit**](https://pre-commit.com/): Format and lint your code with [Ruff](https://docs.astral.sh/ruff/).
-* 🧪 **Tests**: Write tests with [`pytest`](https://docs.pytest.org/en/stable/).
+* 🧪 **Tests**: Write tests with [`pytest`](https://docs.pytest.org/en/stable/), with optional coverage reporting (basic summary or [Codecov](https://about.codecov.io/) integration).
 * 📚 **Documentation**: Write docs in [MyST](https://mystmd.org/) or [MkDocs](https://www.mkdocs.org/).
 * ⚙️ **GitHub Actions**:
     * Deploy documentation to [GitHub Pages](https://docs.github.com/en/pages/getting-started-with-github-pages/creating-a-github-pages-site) or [Read the Docs](https://about.readthedocs.com/).
diff --git a/copier.yml b/copier.yml
@@ -31,6 +31,15 @@ type_check:
     - strict
   default: loose
 
+coverage:
+  type: str
+  help: 'What level of test coverage reporting do you want?'
+  choices:
+    - none
+    - basic
+    - codecov
+  default: none
+
 _subdirectory: template
 _message_after_copy: |
   The `{{package_name}}` package has been created successfully!
diff --git a/docs/developer.md b/docs/developer.md
@@ -27,7 +27,8 @@ Other scripts for the default environment:
 * `check`: Copy/Update the template in the `.tmp` directory and check the rendered files by linting them with `hatch fmt -l`.
 * `clean`: Remove the `.tmp` directory and any Ruff caches.
 * `install`: Copy/Update the template in the `.tmp` directory and install it with `uv pip install`.
-* `test`: Copy/Update the template in the `.tmp` directory run the test suite with `pytest`.
+* `test`: Copy/Update the template in the `.tmp` directory and run the test suite with `pytest`.
+* `test-cov`: Copy/Update the template in the `.tmp` directory and run the test suite with coverage enabled.
 
 ## Documentation
 
diff --git a/docs/index.md b/docs/index.md
@@ -6,9 +6,10 @@ A `copier`-based template for Python packages.
 
 * 📦 **Package management**:
     - Develop with your preferred tools (extras, [`uv`](https://docs.astral.sh/uv/) or [Hatch](https://hatch.pypa.io/)).
+    - Bespoke dev tooling for generating CHANGELOGs automatically based on emoji-typed commit messages.
     - Build your package with [Hatch](https://hatch.pypa.io/). 
 * 🧹 [**Pre-commit**](https://pre-commit.com/): Format and lint your code with [Ruff](https://docs.astral.sh/ruff/).
-* 🧪 **Tests**: Write tests with [`pytest`](https://docs.pytest.org/en/stable/).
+* 🧪 **Tests**: Write tests with [`pytest`](https://docs.pytest.org/en/stable/), with optional coverage reporting (basic summary or [Codecov](https://about.codecov.io/) integration).
 * 📚 **Documentation**: Write docs in [MyST](https://mystmd.org/) or [MkDocs](https://www.mkdocs.org/).
 * ⚙️ **GitHub Actions**:
     * Deploy documentation to [GitHub Pages](https://docs.github.com/en/pages/getting-started-with-github-pages/creating-a-github-pages-site) or [Read the Docs](https://about.readthedocs.com/).
diff --git a/pyproject.toml b/pyproject.toml
@@ -19,6 +19,10 @@ scripts.test = [
   "copier copy --vcs-ref=HEAD . .tmp/py-package -f",
   "cd .tmp/py-package && hatch test -v -- -s",
 ]
+scripts.test-cov = [
+  "copier copy --vcs-ref=HEAD . .tmp/py-package -f",
+  "cd .tmp/py-package && hatch test --cover -v -- -s",
+]
 scripts.clean = [
   "ruff clean",
   "rm -rf .tmp",
diff --git a/template/.github/workflows/ci.yaml b/template/.github/workflows/ci.yaml
diff --git a/template/.github/workflows/ci.yaml.jinja b/template/.github/workflows/ci.yaml.jinja
@@ -0,0 +1,67 @@
+name: ci
+
+on:
+  push:
+    branches:
+      - main
+  pull_request:
+
+jobs:
+  pre-commit:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+
+      - name: Install Python
+        uses: actions/setup-python@v5
+        with:
+          python-version: '3.13'
+
+      - name: Install Hatch
+        run: pip install hatch
+
+      - name: Run pre-commit
+        run: hatch run pre-commit:run --all-files
+
+  tests:
+    runs-on: ubuntu-latest
+    strategy:
+      matrix:
+        python-version: ['3.10', '3.14']
+
+    steps:
+      - uses: actions/checkout@v4
+      - uses: actions/setup-python@v5
+        with:
+          python-version: {% raw %}${{ matrix.python-version }}{% endraw %}
+      - run: pip install hatch
+{%- if coverage == 'none' %}
+      - run: hatch test
+{%- else %}
+      - run: hatch test --cover --cover-min 50
+
+      - name: Install coverage
+        if: always()
+        run: pip install coverage[toml]
+
+      - name: Coverage summary
+        if: always()
+        run: |
+          echo '## Test Coverage' >> $GITHUB_STEP_SUMMARY
+          echo '```' >> $GITHUB_STEP_SUMMARY
+          coverage report >> $GITHUB_STEP_SUMMARY 2>&1 || true
+          echo '```' >> $GITHUB_STEP_SUMMARY
+{%- endif %}
+{%- if coverage == 'codecov' %}
+
+      - name: Generate coverage XML
+        if: always()
+        run: coverage xml
+
+      - name: Upload coverage to Codecov
+        if: always()
+        uses: codecov/codecov-action@v5
+        with:
+          files: coverage.xml
+          fail_ci_if_error: false
+{%- endif %}
diff --git a/template/pyproject.toml.jinja b/template/pyproject.toml.jinja
@@ -82,6 +82,15 @@ run = "pytest {args}"
 
 [[tool.hatch.envs.hatch-test.matrix]]
 python = ["3.10", "3.11", "3.12", "3.13", "3.14"]
+{%- if coverage != 'none' %}
+
+[tool.coverage.run]
+source = ["{{ package_name.lower().replace('-', '_') }}"]
+branch = true
+
+[tool.coverage.report]
+show_missing = true
+{%- endif %}
 
 [tool.ruff]
 lint.ignore = [
diff --git a/template/{% if coverage == 'codecov' %}.codecov.yml{% endif %}.jinja b/template/{% if coverage == 'codecov' %}.codecov.yml{% endif %}.jinja
@@ -0,0 +1,10 @@
+coverage:
+  status:
+    project:
+      default:
+        target: auto
+        threshold: 0%
+    patch:
+      default:
+        target: auto
+        threshold: 0%
