hgext/record.py

wireprototypes: make `baseprotocolhandler` methods abstract

The documentation says it's an abstract base class, so let's enforce it.  The
`typing.Protocol` class is already an ABC, but it only prevents instantiation if
there are abstract attrs that are missing.  For example, from `hg debugshell`:

    >>> from mercurial import wireprototypes
    >>> x = wireprototypes.baseprotocolhandler()
    Traceback (most recent call last):
      File "<console>", line 1, in <module>
    TypeError: Can't instantiate abstract class baseprotocolhandler with abstract method name
    >>> class fake(wireprototypes.baseprotocolhandler):
    ...     pass
    ...
    >>> x = fake()
    Traceback (most recent call last):
      File "<console>", line 1, in <module>
    TypeError: Can't instantiate abstract class fake with abstract method name

That's great, but it doesn't protect against calling non-abstract methods at
runtime, rather it depends on the protocol type hint being added to method
signatures or class attrs, and then running a type checker to notice when an
instance is assigned that doesn't conform to the protocol.  We don't widely use
type hints yet, and do have a lot of class hierarchy in the repository area,
which could lead to surprises like this:

    >>> class fake(wireprototypes.baseprotocolhandler):
    ...     @property
    ...     def name(self) -> bytes:
    ...         return b'name'
    ...
    >>> z = fake()
    >>> z.client()
    >>> print(z.client())
    None

Oops.  That was supposed to return `bytes`.  So not only is a bad/unexpected
value returned, but it's one that violates the type hints (since the base
client() method will be annotated to return bytes).  With this change, we get:

    >>> from mercurial import wireprototypes
    >>> class fake(wireprototypes.baseprotocolhandler):
    ...     @property
    ...     def name(self) -> bytes:
    ...         return b'name'
    ...
    >>> x = fake()
    Traceback (most recent call last):
      File "<console>", line 1, in <module>
    TypeError: Can't instantiate abstract class fake with abstract methods
        addcapabilities, checkperm, client, getargs, getpayload, getprotocaps, mayberedirectstdio

So this looks like a reasonable safety harness to me, and lets us catch problems
by running the standard tests while the type hints are being added, and pytype
is improved.  We should probably do this for all Protocol class methods that
don't supply a method implementation.

# record.py
#
# Copyright 2007 Bryan O'Sullivan <[e-mail]>
#
# This software may be used and distributed according to the terms of the
# GNU General Public License version 2 or any later version.

'''commands to interactively select changes for commit/qrefresh (DEPRECATED)

The feature provided by this extension has been moved into core Mercurial as
:hg:`commit --interactive`.'''

from __future__ import annotations

from mercurial.i18n import _
from mercurial import (
    cmdutil,
    commands,
    error,
    extensions,
    registrar,
)

cmdtable = {}
command = registrar.command(cmdtable)
# 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 = b'ships-with-hg-core'


@command(
    b"record",
    # same options as commit + white space diff options
    [c for c in commands.table[b'commit|ci'][1][:] if c[1] != b"interactive"]
    + cmdutil.diffwsopts,
    _(b'hg record [OPTION]... [FILE]...'),
    helpcategory=command.CATEGORY_COMMITTING,
)
def record(ui, repo, *pats, **opts):
    """interactively select changes to commit

    If a list of files is omitted, all changes reported by :hg:`status`
    will be candidates for recording.

    See :hg:`help dates` for a list of formats valid for -d/--date.

    If using the text interface (see :hg:`help config`),
    you will be prompted for whether to record changes to each
    modified file, and for files with multiple changes, for each
    change to use. For each query, the following responses are
    possible::

      y - record this change
      n - skip this change
      e - edit this change manually

      s - skip remaining changes to this file
      f - record remaining changes to this file

      d - done, skip remaining changes and files
      a - record all changes to all remaining files
      q - quit, recording no changes

      ? - display help

    This command is not available when committing a merge."""

    if not ui.interactive():
        raise error.Abort(
            _(b'running non-interactively, use %s instead') % b'commit'
        )

    opts["interactive"] = True
    overrides = {(b'experimental', b'crecord'): False}
    with ui.configoverride(overrides, b'record'):
        return commands.commit(ui, repo, *pats, **opts)


def qrefresh(origfn, ui, repo, *pats, **opts):
    if not opts['interactive']:
        return origfn(ui, repo, *pats, **opts)

    mq = extensions.find(b'mq')

    def committomq(ui, repo, *pats, **opts):
        # At this point the working copy contains only changes that
        # were accepted. All other changes were reverted.
        # We can't pass *pats here since qrefresh will undo all other
        # changed files in the patch that aren't in pats.
        mq.refresh(ui, repo, **opts)

    # backup all changed files
    cmdutil.dorecord(
        ui, repo, committomq, None, True, cmdutil.recordfilter, *pats, **opts
    )


# This command registration is replaced during uisetup().
@command(
    b'qrecord',
    [],
    _(b'hg qrecord [OPTION]... PATCH [FILE]...'),
    helpcategory=command.CATEGORY_COMMITTING,
    inferrepo=True,
)
def qrecord(ui, repo, patch, *pats, **opts):
    """interactively record a new patch

    See :hg:`help qnew` & :hg:`help record` for more information and
    usage.
    """
    return _qrecord(b'qnew', ui, repo, patch, *pats, **opts)


def _qrecord(cmdsuggest, ui, repo, patch, *pats, **opts):
    try:
        mq = extensions.find(b'mq')
    except KeyError:
        raise error.Abort(_(b"'mq' extension not loaded"))

    repo.mq.checkpatchname(patch)

    def committomq(ui, repo, *pats, **opts):
        opts['checkname'] = False
        mq.new(ui, repo, patch, *pats, **opts)

    overrides = {(b'experimental', b'crecord'): False}
    with ui.configoverride(overrides, b'record'):
        cmdutil.checkunfinished(repo)
        cmdutil.dorecord(
            ui,
            repo,
            committomq,
            cmdsuggest,
            False,
            cmdutil.recordfilter,
            *pats,
            **opts,
        )


def qnew(origfn, ui, repo, patch, *args, **opts):
    if opts['interactive']:
        return _qrecord(None, ui, repo, patch, *args, **opts)
    return origfn(ui, repo, patch, *args, **opts)


def uisetup(ui):
    try:
        mq = extensions.find(b'mq')
    except KeyError:
        return

    cmdtable[b"qrecord"] = (
        qrecord,
        # same options as qnew, but copy them so we don't get
        # -i/--interactive for qrecord and add white space diff options
        mq.cmdtable[b'qnew'][1][:] + cmdutil.diffwsopts,
        _(b'hg qrecord [OPTION]... PATCH [FILE]...'),
    )

    _wrapcmd(b'qnew', mq.cmdtable, qnew, _(b"interactively record a new patch"))
    _wrapcmd(
        b'qrefresh',
        mq.cmdtable,
        qrefresh,
        _(b"interactively select changes to refresh"),
    )


def _wrapcmd(cmd, table, wrapfn, msg):
    entry = extensions.wrapcommand(table, cmd, wrapfn)
    entry[1].append((b'i', b'interactive', None, msg))