procutil: make stream detection in make_line_buffered more correct and strict
In make_line_buffered(), we don’t want to wrap the stream if we know that lines
get flushed to the underlying raw stream already.
Previously, the heuristic was too optimistic. It assumed that any stream which
is not an instance of io.BufferedIOBase doesn’t need wrapping. However, there
are buffered streams that aren’t instances of io.BufferedIOBase, like
Mercurial’s own winstdout.
The new logic is different in two ways:
First, only for the check, if unwraps any combination of WriteAllWrapper and
winstdout.
Second, it skips wrapping the stream only if it is an instance of io.RawIOBase
(or already wrapped). If it is an instance of io.BufferedIOBase, it gets
wrapped. In any other case, the function raises an exception. This ensures
that, if an unknown stream is passed or we add another wrapper in the future,
we don’t wrap the stream if it’s already line buffered or not wrap the stream
if it’s not line buffered. In fact, this was already helpful during development
of this change. Without it, I possibly would have forgot that WriteAllWrapper
needs to be ignored for the check, leading to unnecessary wrapping if stdout is
unbuffered.
The alternative would have been to always wrap unknown streams. However, I
don’t think that anyone would benefit from being less strict. We can expect
streams from the standard library to be subclassing either io.RawIOBase or
io.BufferedIOBase, so running Mercurial in the standard way should not regress
by this change. Py2exe might replace sys.stdout and sys.stderr, but that
currently breaks Mercurial anyway and also these streams don’t claim to be
interactive, so this function is not called for them.
# Copyright 2012 Facebook
#
# This software may be used and distributed according to the terms of the
# GNU General Public License version 2 or any later version.
"""Find tests that newly pass under Python 3.
The approach is simple: we maintain a whitelist of Python 3 passing
tests in the repository, and periodically run all the /other/ tests
and look for new passes. Any newly passing tests get automatically
added to the whitelist.
You probably want to run it like this:
$ cd tests
$ python3 ../contrib/python3-ratchet.py \
> --working-tests=../contrib/python3-whitelist
"""
import argparse
import json
import os
import subprocess
import sys
_hgenv = dict(os.environ)
_hgenv.update(
{
'HGPLAIN': '1',
}
)
_HG_FIRST_CHANGE = '9117c6561b0bd7792fa13b50d28239d51b78e51f'
def _runhg(*args):
return subprocess.check_output(args, env=_hgenv)
def _is_hg_repo(path):
return (
_runhg('hg', 'log', '-R', path, '-r0', '--template={node}').strip()
== _HG_FIRST_CHANGE
)
def _py3default():
if sys.version_info[0] >= 3:
return sys.executable
return 'python3'
def main(argv=()):
p = argparse.ArgumentParser()
p.add_argument(
'--working-tests', help='List of tests that already work in Python 3.'
)
p.add_argument(
'--commit-to-repo',
help='If set, commit newly fixed tests to the given repo',
)
p.add_argument(
'-j',
default=os.sysconf('SC_NPROCESSORS_ONLN'),
type=int,
help='Number of parallel tests to run.',
)
p.add_argument(
'--python3',
default=_py3default(),
help='python3 interpreter to use for test run',
)
p.add_argument(
'--commit-user',
default='python3-ratchet@mercurial-scm.org',
help='Username to specify when committing to a repo.',
)
opts = p.parse_args(argv)
if opts.commit_to_repo:
if not _is_hg_repo(opts.commit_to_repo):
print('abort: specified repository is not the hg repository')
sys.exit(1)
if not opts.working_tests or not os.path.isfile(opts.working_tests):
print(
'abort: --working-tests must exist and be a file (got %r)'
% opts.working_tests
)
sys.exit(1)
elif opts.commit_to_repo:
root = _runhg('hg', 'root').strip()
if not opts.working_tests.startswith(root):
print(
'abort: if --commit-to-repo is given, '
'--working-tests must be from that repo'
)
sys.exit(1)
try:
subprocess.check_call(
[
opts.python3,
'-c',
'import sys ; '
'assert ((3, 5) <= sys.version_info < (3, 6) '
'or sys.version_info >= (3, 6, 2))',
]
)
except subprocess.CalledProcessError:
print(
'warning: Python 3.6.0 and 3.6.1 have '
'a bug which breaks Mercurial'
)
print('(see https://bugs.python.org/issue29714 for details)')
sys.exit(1)
rt = subprocess.Popen(
[
opts.python3,
'run-tests.py',
'-j',
str(opts.j),
'--blacklist',
opts.working_tests,
'--json',
]
)
rt.wait()
with open('report.json') as f:
data = f.read()
report = json.loads(data.split('=', 1)[1])
newpass = set()
for test, result in report.items():
if result['result'] != 'success':
continue
# A new passing test! Huzzah!
newpass.add(test)
if newpass:
# We already validated the repo, so we can just dive right in
# and commit.
if opts.commit_to_repo:
print(len(newpass), 'new passing tests on Python 3!')
with open(opts.working_tests) as f:
oldpass = {l for l in f.read().splitlines() if l}
with open(opts.working_tests, 'w') as f:
for p in sorted(oldpass | newpass):
f.write('%s\n' % p)
_runhg(
'hg',
'commit',
'-R',
opts.commit_to_repo,
'--user',
opts.commit_user,
'--message',
'python3: expand list of passing tests',
)
else:
print('Newly passing tests:', '\n'.join(sorted(newpass)))
sys.exit(2)
if __name__ == '__main__':
main(sys.argv[1:])