view contrib/python3-ratchet.py @ 37497:1541e1a8e87d

filelog: wrap revlog instead of inheriting it (API)

The revlog base class exposes a ton of methods. Inheriting the
revlog class for filelog will make it difficult to expose a
clean interface. There will be abstraction violations.

This commit breaks the inheritance of revlog by the filelog
class. Filelog instances now contain a reference to a revlog
instance. Various properties and methods are now proxied to
that instance.

There is precedence for doing this: manifestlog does something
similar. Although, manifestlog has a cleaner interface than
filelog. We'll get there with filelog...

The new filelog class exposes a handful of extra properties and
methods that aren't part of the declared filelog interface.
Every extra item was added in order to get a test to pass. The
set of tests that failed without these extra proxies has
significant overlap with the set of tests that don't work with
the simple store repo. There should be no surprise there.

Hopefully the hardest part about this commit to review are the
changes to bundlerepo and unionrepo. Both repository types
define a custom revlog or revlog-like class and then have a
custom filelog that inherits from both filelog and their custom
revlog. This code has been changed so the filelog types don't
inherit from revlog. Instead, they replace the revlog instance
on the created filelog. This is super hacky. I plan to fix this
in a future commit by parameterizing filelog.__init__.

Because Python function call overhead is a thing, this change
could impact performance by introducing a nearly empty proxy
function for various methods and properties. I would gladly
measure the performance impact of it, but I'm not sure what
operations have tight loops over filelog attribute lookups
or function calls. I know some of the DAG traversal code can
be sensitive about the performance of e.g. parentrevs(). However,
many of these functions are implemented on the revlog class and
therefore have direct access to self.parentrevs() and aren't
going through a proxy.

.. api::

   filelog.filelog is now a standalone class and doesn't inherit
   from revlog. Instead, it wraps a revlog instance at self._revlog.
   This change was made in an attempt to formalize storage APIs and
   prevent revlog implementation details leaking through to callers.

Differential Revision: https://phab.mercurial-scm.org/D3154

# 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:])