view contrib/python3-ratchet.py @ 42377:0546ead39a7e stable

manifest: avoid corruption by dropping removed files with pure (issue5801)

Previously, removed files would simply be marked by overwriting the first byte
with NUL and dropping their entry in `self.position`.  But no effort was made to
ignore them when compacting the dictionary into text form.  This allowed them to
slip into the manifest revision, since the code seems to be trying to minimize
the string operations by copying as large a chunk as possible.  As part of this,
compact() walks the existing text based on entries in the `positions` list, and
consumed everything up to the next position entry.   This typically resulted in
a ValueError complaining about unsorted manifest entries.

Sometimes it seems that files do get dropped in large repos- it seems to
correspond to there being a new entry that would take the same slot.  A much
more trivial problem is that if the only changes were removals, `_compact()`
didn't even run because `__delitem__` doesn't add anything to `self.extradata`.
Now there's an explicit variable to flag this, both to allow `_compact()` to
run, and to avoid searching the manifest in cases where there are no removals.

In practice, this behavior was mostly obscured by the check in fastdelta() which
takes a different path that explicitly drops removed files if there are fewer
than 1000 changes.  However, timeless has a repo where after rebasing tens of
commits, a totally different path[1] is taken that bypasses the change count
check and hits this problem.

[1] https://www.mercurial-scm.org/repo/hg/file/2338bdea4474/mercurial/manifest.py#l1511

# 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
"""
from __future__ import print_function
from __future__ import absolute_import

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(r'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='[e-mail]',
                   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:])