exchange: reject new compression engines for v1 bundles (issue5506)
Version 1 bundles only support a fixed set of compression engines.
Before this change, we would accept any compression engine for v1
bundles, even those that may not work on v1. This could lead to
an error.
We define a fixed set of compression engines known to work with v1
bundles and we add checking to ensure a newer engine (like zstd)
won't work with v1 bundles.
I also took the liberty of adding test coverage for unknown compression
names because I noticed we didn't have coverage of it before.
#!/usr/bin/env python
#
# check-py3-compat - check Python 3 compatibility of Mercurial files
#
# Copyright 2015 Gregory Szorc <gregory.szorc@gmail.com>
#
# 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 os
import sys
import traceback
def check_compat_py2(f):
"""Check Python 3 compatibility for a file with Python 2"""
with open(f, 'rb') as fh:
content = fh.read()
root = ast.parse(content)
# Ignore empty files.
if not root.body:
return
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)
def check_compat_py3(f):
"""Check Python 3 compatibility of a file with Python 3."""
import importlib # not available on Python 2.6
with open(f, 'rb') as fh:
content = fh.read()
try:
ast.parse(content)
except SyntaxError as e:
print('%s: invalid syntax: %s' % (f, e))
return
# Try to import the module.
# For now we only support mercurial.* and hgext.* modules because figuring
# out module paths for things not in a package can be confusing.
if f.startswith(('hgext/', 'mercurial/')) and not f.endswith('__init__.py'):
assert f.endswith('.py')
name = f.replace('/', '.')[:-3].replace('.pure.', '.')
try:
importlib.import_module(name)
except Exception as e:
exc_type, exc_value, tb = sys.exc_info()
# We walk the stack and ignore frames from our custom importer,
# import mechanisms, and stdlib modules. This kinda/sorta
# emulates CPython behavior in import.c while also attempting
# to pin blame on a Mercurial file.
for frame in reversed(traceback.extract_tb(tb)):
if frame.name == '_call_with_frames_removed':
continue
if 'importlib' in frame.filename:
continue
if 'mercurial/__init__.py' in frame.filename:
continue
if frame.filename.startswith(sys.prefix):
continue
break
if frame.filename:
filename = os.path.basename(frame.filename)
print('%s: error importing: <%s> %s (error at %s:%d)' % (
f, type(e).__name__, e, filename, frame.lineno))
else:
print('%s: error importing module: <%s> %s (line %d)' % (
f, type(e).__name__, e, frame.lineno))
if __name__ == '__main__':
if sys.version_info[0] == 2:
fn = check_compat_py2
else:
fn = check_compat_py3
for f in sys.argv[1:]:
fn(f)
sys.exit(0)