util: enable observing of util.bufferedinputpipe
Our file object proxy is useful. But it doesn't capture all I/O.
The "os" module offers low-level interfaces to various system calls.
For example, os.read() exposes read(2) to read from a file
descriptor.
bufferedinputpipe is special in a few ways. First, it acts as a
proxy of sorts around our [potentially proxied] file object. In
addition, it uses os.read() to satisfy all I/O. This means that
our observer doesn't see notifications for reads on this type.
This is preventing us from properly instrumenting reads on ssh
peers.
This commit teaches bufferedinputpipe to be aware of our
observed file objects. We do this by introducing a class variation
that notifies our observer of os.read() events. Since read()
and readline() bypass os.read(), we also teach this instance
to notify the observer for buffered variations of these reads as
well. We don't report them as actual read() and readline() calls
because these methods are never called on the actual file object
but rather a buffered version of it.
We introduce bufferedinputpipe.__new__ to swap in the new class
if the passed file object is a fileobjectproxy. This makes hooking
up the observer automatic. And it is a zero cost abstraction for
I/O operations on non-proxied file objects.
Differential Revision: https://phab.mercurial-scm.org/D2404
# amend.py - provide the amend command
#
# Copyright 2017 Facebook, Inc.
#
# This software may be used and distributed according to the terms of the
# GNU General Public License version 2 or any later version.
"""provide the amend command (EXPERIMENTAL)
This extension provides an ``amend`` command that is similar to
``commit --amend`` but does not prompt an editor.
"""
from __future__ import absolute_import
from mercurial.i18n import _
from mercurial import (
cmdutil,
commands,
error,
pycompat,
registrar,
)
# Note for extension authors: ONLY specify testedwith = 'ships-with-hg-core' for
# extensions which SHIP WITH MERCURIAL. Non-mainline extensions should
# be specifying the version(s) of Mercurial they are tested with, or
# leave the attribute unspecified.
testedwith = 'ships-with-hg-core'
cmdtable = {}
command = registrar.command(cmdtable)
@command('amend',
[('A', 'addremove', None,
_('mark new/missing files as added/removed before committing')),
('e', 'edit', None, _('invoke editor on commit messages')),
('i', 'interactive', None, _('use interactive mode')),
('n', 'note', '', _('store a note on the amend')),
] + cmdutil.walkopts + cmdutil.commitopts + cmdutil.commitopts2,
_('[OPTION]... [FILE]...'),
inferrepo=True)
def amend(ui, repo, *pats, **opts):
"""amend the working copy parent with all or specified outstanding changes
Similar to :hg:`commit --amend`, but reuse the commit message without
invoking editor, unless ``--edit`` was set.
See :hg:`help commit` for more details.
"""
opts = pycompat.byteskwargs(opts)
if len(opts['note']) > 255:
raise error.Abort(_("cannot store a note of more than 255 bytes"))
with repo.wlock(), repo.lock():
if not opts.get('logfile'):
opts['message'] = opts.get('message') or repo['.'].description()
opts['amend'] = True
return commands._docommit(ui, repo, *pats, **pycompat.strkwargs(opts))