CI scripts, again

Author: Technologicat

.github/workflows/coverage.yml

@@ -23,19 +23,19 @@ jobs:
       uses: actions/setup-python@v2
       with:
         python-version: ${{ matrix.python-version }}
-    - name: Install tools
+    - name: Install tools in CI virtualenv
       run: |
         python -m pip install --upgrade pip
         pip install flake8
         pip install pdm
-    - name: Create virtualenv and install dependencies
+    - name: Create in-project virtualenv and install dependencies
       run: |
         pdm python install ${{ matrix.python-version }}
         # "When you run pdm install the first time on a new PDM-managed project, whose Python interpreter is not decided yet,
         #  PDM will create a virtualenv in <project_root>/.venv, and install dependencies into it."
-        #     --https://pdm-project.org/en/latest/usage/venv/
+        #     https://pdm-project.org/en/latest/usage/venv/
         pdm install
-    - name: Install coverage tool in virtualenv
+    - name: Install coverage tool in in-project virtualenv
       run: |
         pdm run python -m ensurepip
         pdm run python -m pip install coverage

.github/workflows/python-package.yml

@@ -25,7 +25,7 @@ jobs:
       uses: actions/setup-python@v2
       with:
         python-version: ${{ matrix.python-version }}
-    - name: Install tools
+    - name: Install tools in CI venv
       run: |
         python -m pip install --upgrade pip
         pip install flake8
@@ -36,12 +36,19 @@ jobs:
         flake8 . --config=flake8rc --count --select=E9,F63,F7,F82 --show-source --statistics
         # exit-zero treats all errors as warnings. The GitHub editor is 127 chars wide
         flake8 . --config=flake8rc --count --exit-zero --max-complexity=100 --max-line-length=127 --statistics
-    - name: Create virtualenv and install dependencies
+    - name: Determine Python version string for PDM
       run: |
-        pdm python install ${{ matrix.python-version }}
+        TARGET_PYTHON_VERSION_FOR_PDM=$( python -c 'import sys; v = sys.argv[1]; print(v if "-" not in v else v.replace("-", "@"))' ${{ matrix.python-version }} )
+        # We need this hack at all because CI expects e.g. "pypy-3.10", whereas PDM expects "[email protected]".
+        # Now that we have the result, send it to an environment variable so that the next step can use it.
+        #     https://docs.github.com/en/actions/writing-workflows/choosing-what-your-workflow-does/workflow-commands-for-github-actions#setting-an-environment-variable
+        echo "TARGET_PYTHON_VERSION=$TARGET_PYTHON_VERSION_FOR_PDM" >> "$GITHUB_ENV"
+    - name: Create in-project virtualenv and install dependencies
+      run: |
+        pdm python install "$TARGET_PYTHON_VERSION_FOR_PDM"
         # "When you run pdm install the first time on a new PDM-managed project, whose Python interpreter is not decided yet,
         #  PDM will create a virtualenv in <project_root>/.venv, and install dependencies into it."
-        #     --https://pdm-project.org/en/latest/usage/venv/
+        #     https://pdm-project.org/en/latest/usage/venv/
         pdm install
     - name: Test with unpythonic.test.fixtures
       run: |