some helpers for fixups in exercise branches

reset-exercise-branches.py

@@ -0,0 +1,29 @@
+#!/usr/bin/env python
+import subprocess
+from pathlib import Path
+from chapters import CHAPTERS
+
+
+def run(cmds):
+    print(' '.join(cmds))
+    p = subprocess.run(
+        cmds,
+        cwd=Path(__file__).parent / 'code',
+        capture_output=True,
+    )
+    if p.returncode:
+        raise Exception(p.stderr.decode())
+    output = p.stdout.decode()
+    print(output)
+    return output
+
+
+all_branches = run(['git', 'branch', '-a'],)
+
+for chapter in CHAPTERS:
+    exercise_chapter = f'{chapter}_exercise'
+    if exercise_chapter not in all_branches:
+        continue
+    run(['git', 'checkout', exercise_chapter])
+    run(['git', 'reset', '--hard', f'origin/{exercise_chapter}'])
+run(['git', 'checkout', 'master'])

update-exercise-branches.py

@@ -0,0 +1,37 @@
+#!/usr/bin/env python
+import sys
+import subprocess
+from pathlib import Path
+
+
+def run(cmds):
+    print(' '.join(cmds))
+    p = subprocess.run(
+        cmds,
+        cwd=Path(__file__).parent / 'code',
+        capture_output=True,
+    )
+    if p.returncode:
+        raise Exception(p.stderr.decode())
+    output = p.stdout.decode()
+    print(output)
+    return output
+
+all_branches = run(['git', 'branch', '-a'],)
+
+
+def main(chapter):
+    exercise_chapter = f'{chapter}_exercise'
+    assert exercise_chapter in all_branches
+
+    run(['git', 'checkout', exercise_chapter])
+    commits = list(reversed(run([
+        'git', 'log', '--pretty=%h',
+        f'{exercise_chapter}^{{/{chapter}_ends}}..{exercise_chapter}',
+    ]).split()))
+    run(['git', 'reset', '--hard', chapter])
+    run(['git', 'cherry-pick', *commits])
+
+if __name__ == '__main__':
+    chapter = sys.argv[1]
+    main(chapter)