+def mergeHistory(old_pkg, new_pkg, n):
+ n = int(n)
+
+ subprocess.check_call(['git', 'push',
+ '../%s.git' % new_pkg,
+ 'master:refs/heads/%s' % old_pkg],
+ cwd='%s.git' % old_pkg)
+
+ # Find the merge commit
+ if n == 0:
+ p = subprocess.Popen(['git', 'rev-parse',
+ 'base'],
+ cwd='%s.git' % new_pkg,
+ stdout=subprocess.PIPE)
+ else:
+ p = subprocess.Popen(['git', 'rev-list',
+ '--reverse',
+ '--boundary',
+ '--skip=%s' % (n - 1),
+ 'base..master'],
+ cwd='%s.git' % new_pkg,
+ stdout=subprocess.PIPE)
+ p.wait()
+ new_rev = p.stdout.read().split()[0].strip('-')
+
+ # Find any other parents of the merge commit
+ p = subprocess.Popen(['git', 'log',
+ '-1',
+ '--pretty=format:%P',
+ new_rev],
+ cwd='%s.git' % new_pkg,
+ stdout=subprocess.PIPE)
+ p.wait()
+ parents = p.stdout.read().split()
+
+ # Find the additional parent we're adding
+ p = subprocess.Popen(['git', 'rev-parse',
+ old_pkg],
+ cwd='%s.git' % new_pkg,
+ stdout=subprocess.PIPE)
+ p.wait()
+ parents.append(p.stdout.read().strip())
+
+ # Write out the grafts file
+ f = open('%s.git/info/grafts' % new_pkg, 'a')
+ print >>f, '%s %s' % (new_rev, ' '.join(parents))
+ f.close()
+
+ # Run filter-branch
+ subprocess.call(['git', 'filter-branch',
+ '--tag-name-filter', 'cat',
+ '--',
+ '--all'],
+ cwd='%s.git' % new_pkg)
+
+ subprocess.call(['git', 'branch',
+ '-D',
+ old_pkg],
+ cwd='%s.git' % new_pkg)
+ shutil.rmtree('%s.git/refs/original' % new_pkg, True)
+
+def mergeHistories():
+ merges = []
+ for line in open('merges'):
+ line = line.strip()
+ if line == '' or line[0] == '#':
+ continue
+
+ merges.append(line.split())
+
+ for merge in merges:
+ mergeHistory(*merge)
+
+ for merge in merges:
+ shutil.rmtree('%s.git' % merge[0])
+