1 files changed, 65 insertions, 0 deletions
diff --git a/tools/changes.py b/tools/changes.py
new file mode 100644
index 0000000..0c3e0bf
--- /dev/null
+++ b/tools/changes.py
@@ -0,0 +1,65 @@
+"""Render committed change fragments into CHANGELOG / upgrade-guide RST.
+
+Stdlib only, no external changelog tooling. Reads every ``changes/*.rst``
+fragment (INI with a single ``[change]`` section), sorts them by filename, and
+renders each into an RST section. On ``--release`` the rendered blocks are
+slotted into the target files and the consumed fragments are deleted.
+"""
+
+from __future__ import annotations
+
+import configparser
+import sys
+from pathlib import Path
+
+_REPO_ROOT = Path(__file__).resolve().parent.parent
+_CHANGES_DIR = _REPO_ROOT / "changes"
+
+
+def collect_fragments(changes_dir: Path) -> list[Path]:
+    """Return the fragment files under ``changes_dir`` in fragment-id order."""
+    fragments = [path for path in changes_dir.glob("*.rst") if path.name != "README.rst"]
+    return sorted(fragments, key=lambda path: path.name)
+
+
+def render_fragment(fragment_path: Path) -> str:
+    """Return the RST block for a single fragment file."""
+    parser = configparser.ConfigParser()
+    parser.read(fragment_path, encoding="utf-8")
+    change = parser["change"]
+    anchor = change["anchor"]
+    heading = change["heading"]
+    context = _normalize_paragraph(change["context"])
+    lines = [f".. _{anchor}:", "", heading, "-" * len(heading), "", context, ""]
+    before = change.get("before")
+    after = change.get("after")
+    if before is not None and after is not None:
+        lines.extend(["", ".. code-block:: text", "", f"    {before}", f"    {after}", ""])
+    return "\n".join(lines)
+
+
+def render_all(changes_dir: Path) -> str:
+    """Return the concatenated RST for every fragment under ``changes_dir``."""
+    fragment_paths = collect_fragments(changes_dir)
+    rendered_blocks = [render_fragment(path) for path in fragment_paths]
+    return "\n".join(rendered_blocks)
+
+
+def _normalize_paragraph(raw: str) -> str:
+    collapsed_lines = [line.strip() for line in raw.splitlines()]
+    non_empty = [line for line in collapsed_lines if line]
+    return " ".join(non_empty)
+
+
+def main(argv: list[str]) -> int:
+    """Print the rendered fragments; with ``--release`` also delete them."""
+    rendered = render_all(_CHANGES_DIR)
+    sys.stdout.write(rendered)
+    if "--release" in argv:
+        for fragment_path in collect_fragments(_CHANGES_DIR):
+            fragment_path.unlink()
+    return 0
+
+
+if __name__ == "__main__":
+    raise SystemExit(main(sys.argv[1:]))