ci: make Python validation authoritative (#5940)

Co-authored-by: Alexandre Teixeira <111787685+alteixeira20@users.noreply.github.com>

tests/test_ci_authoritative_validation.py

@@ -0,0 +1,35 @@
+"""Regression coverage for authoritative Python CI validation."""
+
+import re
+from pathlib import Path
+
+
+_WORKFLOW = (
+    Path(__file__).resolve().parent.parent / ".github" / "workflows" / "ci.yml"
+)
+
+
+def _indented_block(text: str, heading: str, indent: int) -> str:
+    pattern = re.compile(
+        rf"(?ms)^{' ' * indent}{re.escape(heading)}:\n"
+        rf"(?P<body>(?:(?:{' ' * (indent + 2)}.*|\s*)\n)*)"
+    )
+    match = pattern.search(text)
+    assert match is not None, f"missing {heading!r} block"
+    return match.group(0)
+
+
+def test_ci_runs_on_integrated_dev_pushes():
+    workflow = _WORKFLOW.read_text()
+    push = _indented_block(workflow, "push", 2)
+
+    assert re.search(r"(?m)^    branches:\s*\[main,\s*dev\]\s*$", push)
+    assert "paths-ignore:" not in push
+
+
+def test_python_tests_are_authoritative():
+    workflow = _WORKFLOW.read_text()
+    python_tests = _indented_block(workflow, "python-tests", 2)
+
+    assert "python -m pytest -q" in python_tests
+    assert "continue-on-error:" not in python_tests