comparison mercurial/extensions.py @ 34087:5361771f9714

wrapfunction: use functools.partial if possible

Every `extensions.bind` call inserts a frame in traceback:

   ... in closure
     return func(*(args + a), **kw)

which makes traceback noisy.

The Python stdlib has a `functools.partial` which is backed by C code and
does not pollute traceback. However it does not support instancemethod and
sets `args` attribute which could be problematic for alias handling.

This patch makes `wrapfunction` use `functools.partial` if we are wrapping a
function directly exported by a module (so it's impossible to be a class or
instance method), and special handles `wrapfunction` results so alias
handling code could handle `args` just fine.

As an example, `hg rebase -s . -d . --traceback` got 6 lines removed in my
setup:

   File "hg/mercurial/dispatch.py", line 898, in _dispatch
     cmdpats, cmdoptions)
  -File "hg/mercurial/extensions.py", line 333, in closure
  -  return func(*(args + a), **kw)
   File "hg/hgext/journal.py", line 84, in runcommand
     return orig(lui, repo, cmd, fullargs, *args)
  -File "hg/mercurial/extensions.py", line 333, in closure
  -  return func(*(args + a), **kw)
   File "fb-hgext/hgext3rd/fbamend/hiddenoverride.py", line 119, in runcommand
     result = orig(lui, repo, cmd, fullargs, *args)
   File "hg/mercurial/dispatch.py", line 660, in runcommand
     ret = _runcommand(ui, options, cmd, d)
  -File "hg/mercurial/extensions.py", line 333, in closure
  -  return func(*(args + a), **kw)
   File "hg/hgext/pager.py", line 69, in pagecmd
     return orig(ui, options, cmd, cmdfunc)
   ....

Differential Revision: https://phab.mercurial-scm.org/D632

34086:a39dce4a76b8

# This software may be used and distributed according to the terms of the
# GNU General Public License version 2 or any later version.

from __future__ import absolute_import

import imp
import inspect
import os

from .i18n import (

        return func(*(args + a), **kw)
    return closure

def _updatewrapper(wrap, origfn, unboundwrapper):
    '''Copy and add some useful attributes to wrapper'''
    wrap.__module__ = getattr(origfn, '__module__')
    wrap.__doc__ = getattr(origfn, '__doc__')
    wrap.__dict__.update(getattr(origfn, '__dict__', {}))
    wrap._origfunc = origfn
    wrap._unboundwrapper = unboundwrapper

    '''
    assert callable(wrapper)

    origfn = getattr(container, funcname)
    assert callable(origfn)
    wrap = bind(wrapper, origfn)
    _updatewrapper(wrap, origfn, wrapper)
    setattr(container, funcname, wrap)
    return origfn

def unwrapfunction(container, funcname, wrapper=None):

34087:5361771f9714

# This software may be used and distributed according to the terms of the
# GNU General Public License version 2 or any later version.

from __future__ import absolute_import

import functools
import imp
import inspect
import os

from .i18n import (

        return func(*(args + a), **kw)
    return closure

def _updatewrapper(wrap, origfn, unboundwrapper):
    '''Copy and add some useful attributes to wrapper'''
    wrap.__name__ = origfn.__name__
    wrap.__module__ = getattr(origfn, '__module__')
    wrap.__doc__ = getattr(origfn, '__doc__')
    wrap.__dict__.update(getattr(origfn, '__dict__', {}))
    wrap._origfunc = origfn
    wrap._unboundwrapper = unboundwrapper

    '''
    assert callable(wrapper)

    origfn = getattr(container, funcname)
    assert callable(origfn)
    if inspect.ismodule(container):
        # origfn is not an instance or class method. "partial" can be used.
        # "partial" won't insert a frame in traceback.
        wrap = functools.partial(wrapper, origfn)
    else:
        # "partial" cannot be safely used. Emulate its effect by using "bind".
        # The downside is one more frame in traceback.
        wrap = bind(wrapper, origfn)
    _updatewrapper(wrap, origfn, wrapper)
    setattr(container, funcname, wrap)
    return origfn

def unwrapfunction(container, funcname, wrapper=None):