Add cpython-sync script

jaraco/develop/cpython-sync.py

@@ -0,0 +1,66 @@
+"""
+Sync files from an upstream CPython release.
+"""
+
+import json
+import pathlib
+import subprocess
+import re
+
+import autocommand
+import packaging.version
+from requests_toolbelt import sessions
+
+
+gh_content = sessions.BaseUrlSession(
+    'https://raw.githubusercontent.com/python/cpython/'
+)
+gh_api = sessions.BaseUrlSession('https://api.github.com/repos/python/cpython/')
+
+
+def load_file_map():
+    text = pathlib.Path('file map.json').read_text(encoding='utf-8')
+    clean = re.sub('^#.*', '', text, re.MULTILINE)
+    return json.loads(clean)
+
+
+class Version(packaging.version.Version):
+    @property
+    def is_stable(self):
+        """
+        Include release candidates in stable.
+        """
+        return not self.is_prerelease or self.is_rc
+
+    @property
+    def is_rc(self):
+        return self.pre[1:] == ['rc']
+
+
+def by_tag(tag):
+    return Version(tag['name'])
+
+
+def is_stable(tag):
+    return not by_tag(tag).is_stable
+
+
+@autocommand.autocommand(__name__)
+def run(pre=False):
+    tags = gh_api.get('tags').json()
+    filtered = tags if pre else filter(is_stable, tags)
+    tag = max(filtered, key=by_tag)
+    version = tag['name']
+    for src, dst in load_file_map().items():
+        resp = gh_content.get(f'{version}/{src}')
+        resp.raise_for_status()
+        with open(dst, 'wb') as out:
+            out.write(resp.content)
+    cmd = [
+        'git',
+        'commit',
+        '-a',
+        '-m',
+        f'cpython-{version} rev={tag["commit"]["sha"][:12]}',
+    ]
+    subprocess.run(cmd)

newsfragments/+b9d13ee1.feature.rst

@@ -0,0 +1 @@
+Adding script for syncing a backport (configparser, singledispatch) to a CPython branch.