+
−#!/usr/bin/env python
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−#
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−# check-py3-compat - check Python 3 compatibility of Mercurial files
+
−#
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−# Copyright 2015 Gregory Szorc <gregory.szorc@gmail.com>
+
−#
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−# This software may be used and distributed according to the terms of the
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−# GNU General Public License version 2 or any later version.
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−
+
−from __future__ import absolute_import, print_function
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−
+
−import ast
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−import importlib
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−import os
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−import sys
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−import traceback
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−import warnings
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−
+
−def check_compat_py2(f):
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−    """Check Python 3 compatibility for a file with Python 2"""
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−    with open(f, 'rb') as fh:
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−        content = fh.read()
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−    root = ast.parse(content)
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−
+
−    # Ignore empty files.
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−    if not root.body:
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−        return
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−
+
−    futures = set()
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−    haveprint = False
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−    for node in ast.walk(root):
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−        if isinstance(node, ast.ImportFrom):
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−            if node.module == '__future__':
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−                futures |= set(n.name for n in node.names)
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−        elif isinstance(node, ast.Print):
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−            haveprint = True
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−
+
−    if 'absolute_import' not in futures:
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−        print('%s not using absolute_import' % f)
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−    if haveprint and 'print_function' not in futures:
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−        print('%s requires print_function' % f)
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−
+
−def check_compat_py3(f):
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−    """Check Python 3 compatibility of a file with Python 3."""
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−    with open(f, 'rb') as fh:
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−        content = fh.read()
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−
+
−    try:
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−        ast.parse(content, filename=f)
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−    except SyntaxError as e:
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−        print('%s: invalid syntax: %s' % (f, e))
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−        return
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−
+
−    # Try to import the module.
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−    # For now we only support modules in packages because figuring out module
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−    # paths for things not in a package can be confusing.
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−    if (f.startswith(('hgdemandimport/', 'hgext/', 'mercurial/'))
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−        and not f.endswith('__init__.py')):
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−        assert f.endswith('.py')
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−        name = f.replace('/', '.')[:-3]
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−        try:
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−            importlib.import_module(name)
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−        except Exception as e:
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−            exc_type, exc_value, tb = sys.exc_info()
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−            # We walk the stack and ignore frames from our custom importer,
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−            # import mechanisms, and stdlib modules. This kinda/sorta
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−            # emulates CPython behavior in import.c while also attempting
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−            # to pin blame on a Mercurial file.
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−            for frame in reversed(traceback.extract_tb(tb)):
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−                if frame.name == '_call_with_frames_removed':
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−                    continue
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−                if 'importlib' in frame.filename:
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−                    continue
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−                if 'mercurial/__init__.py' in frame.filename:
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−                    continue
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−                if frame.filename.startswith(sys.prefix):
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−                    continue
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−                break
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−
+
−            if frame.filename:
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−                filename = os.path.basename(frame.filename)
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−                print('%s: error importing: <%s> %s (error at %s:%d)' % (
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−                      f, type(e).__name__, e, filename, frame.lineno))
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−            else:
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−                print('%s: error importing module: <%s> %s (line %d)' % (
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−                      f, type(e).__name__, e, frame.lineno))
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−
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−if __name__ == '__main__':
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−    if sys.version_info[0] == 2:
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−        fn = check_compat_py2
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−    else:
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−        fn = check_compat_py3
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−
+
−    for f in sys.argv[1:]:
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−        with warnings.catch_warnings(record=True) as warns:
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−            fn(f)
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−
+
−        for w in warns:
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−            print(warnings.formatwarning(w.message, w.category,
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−                                         w.filename, w.lineno).rstrip())
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−
+
−    sys.exit(0)