Setup towncrier to generate release notes

newsfragments/validate_files.py

@@ -0,0 +1,32 @@
+#!/usr/bin/env python3
+
+# Towncrier silently ignores files that do not match the expected ending.
+# We use this script to ensure we catch these as errors in CI.
+
+import os
+import pathlib
+
+ALLOWED_EXTENSIONS = {
+    '.bugfix.rst',
+    '.doc.rst',
+    '.feature.rst',
+    '.misc.rst',
+    '.performance.rst',
+    '.removal.rst',
+}
+
+ALLOWED_FILES = {
+    'validate_files.py',
+    'README.md',
+}
+
+THIS_DIR = pathlib.Path(__file__).parent
+
+for fragment_file in THIS_DIR.iterdir():
+
+    if fragment_file.name in ALLOWED_FILES:
+        continue
+
+    full_extension = "".join(fragment_file.suffixes)
+    if full_extension not in ALLOWED_EXTENSIONS:
+        raise Exception(f"Unexpected file: {fragment_file}")