view contrib/check-py3-compat.py @ 28189:fac3a24be50e

rebase: choose default destination the same way as 'hg merge' (BC)

This changeset finally make 'hg rebase' choose its default destination using the
same logic as 'hg merge'. The previous default was "tipmost changeset on the
current branch", the new default is "the other head if there is only one".  This
change has multiple consequences:

- Multiple tests which were not rebasing anything (rebasing from tipmost head)
  are now rebasing on the other "lower" branch. This is the expected new
  behavior.

- A test is now explicitly aborting when there is too many heads on the branch.
  This is the expected behavior.

- We gained a better detection of the "nothing to rebase" case while performing
  'hg pull --rebase' so the message have been updated. Making clearer than an
  update was performed and why. This is beneficial side-effect.

- Rebasing from an active bookmark will behave the same as 'hg merge' from a
  bookmark.

#!/usr/bin/env python
#
# check-py3-compat - check Python 3 compatibility of Mercurial files
#
# Copyright 2015 Gregory Szorc <[e-mail]>
#
# This software may be used and distributed according to the terms of the
# GNU General Public License version 2 or any later version.

from __future__ import absolute_import, print_function

import ast
import sys

def check_compat(f):
    """Check Python 3 compatibility for a file."""
    with open(f, 'rb') as fh:
        content = fh.read()

    # Ignore empty files.
    if not content.strip():
        return

    root = ast.parse(content)
    futures = set()
    haveprint = False
    for node in ast.walk(root):
        if isinstance(node, ast.ImportFrom):
            if node.module == '__future__':
                futures |= set(n.name for n in node.names)
        elif isinstance(node, ast.Print):
            haveprint = True

    if 'absolute_import' not in futures:
        print('%s not using absolute_import' % f)
    if haveprint and 'print_function' not in futures:
        print('%s requires print_function' % f)

if __name__ == '__main__':
    for f in sys.argv[1:]:
        check_compat(f)

    sys.exit(0)