Use pytest to run Python code snippets (#389)

.github/workflows/ci.yaml

@@ -31,7 +31,7 @@ jobs:
       - name: Set up Graphviz
         uses: ts-graphviz/setup-graphviz@v1
 
-      - run: find docs/src/python -type f | xargs -n 1 bash -c 'python -W error $0 || exit 255'
+      - run: pytest
 
   black:
     runs-on: ubuntu-latest

.gitignore

@@ -8,6 +8,7 @@
 # Python
 /.venv
 __pycache__
+.pytest_cache/
 
 # Project
 /docs/data/

Makefile

@@ -43,9 +43,9 @@ lint: .venv  ## Lint code examples
 # python
 	$(VENV_BIN)/black --check .
 
-.PHONY: test-python
-test-python: .venv  ## Test Python code examples
-	find docs/src/python -type f | xargs -n 1 bash -c '$(VENV_BIN)/python -W error $$0 || exit 255'
+.PHONY: test
+test: .venv  ## Test Python code examples
+	$(VENV_BIN)/pytest
 
 .PHONY: help
 help:  ## Display this help screen

pyproject.toml

@@ -0,0 +1,5 @@
+[tool.pytest.ini_options]
+filterwarnings = [
+  "error",
+  "ignore:Matplotlib is currently using agg:UserWarning",
+]

requirements.txt

@@ -11,3 +11,4 @@ markdown-exec[ansi]==1.6.0
 PyGithub==1.59.1
 
 black==23.7.0
+pytest==7.4.0

tests/test_python.py

@@ -0,0 +1,16 @@
+"""Run all Python code snippets."""
+import matplotlib
+import pytest
+import runpy
+from pathlib import Path
+
+# Do not show plots
+matplotlib.use("Agg")
+
+python_snippets_dir = Path(__file__).parent.parent / "docs" / "src" / "python"
+snippets = list(python_snippets_dir.rglob("*.py"))
+
+
+@pytest.mark.parametrize("snippet", snippets)
+def test_run_python_snippets(snippet):
+    runpy.run_path(snippet)