view contrib/python3-ratchet.py @ 50336:cf4d2f31660d stable

chg: populate CHGHG if not set

Normally, chg determines which `hg` executable to use by first consulting the
`$CHGHG` and `$HG` environment variables, and if neither are present defaults
to the `hg` found in the user's `$PATH`. If built with the `HGPATHREL` compiler
flag, chg will instead assume that there exists an `hg` executable in the same
directory as the `chg` binary and attempt to use that.

This can cause problems in situations where there are multiple actively-used
Mercurial installations on the same system. When a `chg` client connects to a
running command server, the server process performs some basic validation to
determine whether a new command server needs to be spawned. These checks include
things like checking certain "sensitive" environment variables and config
sections, as well as checking whether the mtime of the extensions, hg's
`__version__.py` module, and the Python interpreter have changed.

Crucially, the command server doesn't explicitly check whether the executable it
is running from matches the executable that the `chg` client would have
otherwise invoked had there been no existing command server process. Without
`HGPATHREL`, this still gets implicitly checked during the validation step,
because the only way to specify an alternate hg executable (apart from `$PATH`)
is via the `$CHGHG` and `$HG` environment variables, both of which are checked.

With `HGPATHREL`, however, the command server has no way of knowing which hg
executable the client would have run. This means that a client located at
`/version_B/bin/chg` will happily connect to a command server running
`/version_A/bin/hg` instead of `/version_B/bin/hg` as expected. A simple
solution is to have the client set `$CHGHG` itself, which then allows the
command server's environment validation to work as intended.

I have tested this manually using two locally built hg installations and it
seems to work with no ill effects. That said, I'm not sure how to write an
automated test for this since the `chg` available to the tests isn't even built
with the `HGPATHREL` compiler flag to begin with.

# 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='[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:])