docs: update changelog and add script to help generate it (#2733)

tools/make_changelog.py

@@ -0,0 +1,50 @@
+#!/usr/bin/env python3
+# -*- coding: utf-8 -*-
+
+import re
+
+import ghapi.core
+
+
+ENTRY = re.compile(
+    r"""
+    Suggested \s changelog \s entry:
+    .*
+    ```rst
+    \s*
+    (.*?)
+    \s*
+    ```
+""",
+    re.DOTALL | re.VERBOSE,
+)
+
+
+api = ghapi.core.GhApi(owner="pybind", repo="pybind11")
+
+issues = api.issues.list_for_repo(labels="needs changelog", state="closed")
+missing = []
+
+for issue in issues:
+    changelog = ENTRY.findall(issue.body)
+    if changelog:
+        (msg,) = changelog
+        if not msg.startswith("* "):
+            msg = "* " + msg
+        if not msg.endswith("."):
+            msg += "."
+
+        print(msg)
+        print(f"  `#{issue.number} <{issue.html_url}>`_\n")
+
+    else:
+        missing.append(issue)
+
+if missing:
+    print()
+    print("-" * 30)
+    print()
+
+    for issue in missing:
+        print(f"Missing: {issue.title}")
+        print(f"  {issue.html_url}")