view mercurial/hook.py @ 9315:fb66a7d3f28f

dispatch: also pass level argument to __import__ for ignored modules

I wanted to check if mercurial.demandimport could speed up the loading of
PyObjC, and ran into this: the level argument for __import__, available in
Python 2.5 and later, is silently dropped when doing an 'import *'. I have no
idea what these arguments mean, but this minor change made it work.

(Oh, and because of that 'from ... import *', PyObjC still took about 2s...)

# hook.py - hook support for mercurial
#
# Copyright 2007 Matt Mackall <[e-mail]>
#
# This software may be used and distributed according to the terms of the
# GNU General Public License version 2, incorporated herein by reference.

from i18n import _
import os, sys
import extensions, util

def _pythonhook(ui, repo, name, hname, funcname, args, throw):
    '''call python hook. hook is callable object, looked up as
    name in python module. if callable returns "true", hook
    fails, else passes. if hook raises exception, treated as
    hook failure. exception propagates if throw is "true".

    reason for "true" meaning "hook failed" is so that
    unmodified commands (e.g. mercurial.commands.update) can
    be run as hooks without wrappers to convert return values.'''

    ui.note(_("calling hook %s: %s\n") % (hname, funcname))
    obj = funcname
    if not hasattr(obj, '__call__'):
        d = funcname.rfind('.')
        if d == -1:
            raise util.Abort(_('%s hook is invalid ("%s" not in '
                               'a module)') % (hname, funcname))
        modname = funcname[:d]
        try:
            obj = __import__(modname)
        except ImportError:
            try:
                # extensions are loaded with hgext_ prefix
                obj = __import__("hgext_%s" % modname)
            except ImportError:
                raise util.Abort(_('%s hook is invalid '
                                   '(import of "%s" failed)') %
                                 (hname, modname))
        try:
            for p in funcname.split('.')[1:]:
                obj = getattr(obj, p)
        except AttributeError:
            raise util.Abort(_('%s hook is invalid '
                               '("%s" is not defined)') %
                             (hname, funcname))
        if not hasattr(obj, '__call__'):
            raise util.Abort(_('%s hook is invalid '
                               '("%s" is not callable)') %
                             (hname, funcname))
    try:
        r = obj(ui=ui, repo=repo, hooktype=name, **args)
    except KeyboardInterrupt:
        raise
    except Exception, exc:
        if isinstance(exc, util.Abort):
            ui.warn(_('error: %s hook failed: %s\n') %
                         (hname, exc.args[0]))
        else:
            ui.warn(_('error: %s hook raised an exception: '
                           '%s\n') % (hname, exc))
        if throw:
            raise
        ui.traceback()
        return True
    if r:
        if throw:
            raise util.Abort(_('%s hook failed') % hname)
        ui.warn(_('warning: %s hook failed\n') % hname)
    return r

def _exthook(ui, repo, name, cmd, args, throw):
    ui.note(_("running hook %s: %s\n") % (name, cmd))

    env = {}
    for k, v in args.iteritems():
        if hasattr(v, '__call__'):
            v = v()
        env['HG_' + k.upper()] = v

    if repo:
        cwd = repo.root
    else:
        cwd = os.getcwd()
    r = util.system(cmd, environ=env, cwd=cwd)
    if r:
        desc, r = util.explain_exit(r)
        if throw:
            raise util.Abort(_('%s hook %s') % (name, desc))
        ui.warn(_('warning: %s hook %s\n') % (name, desc))
    return r

_redirect = False
def redirect(state):
    global _redirect
    _redirect = state

def hook(ui, repo, name, throw=False, **args):
    r = False

    if _redirect:
        # temporarily redirect stdout to stderr
        oldstdout = os.dup(sys.__stdout__.fileno())
        os.dup2(sys.__stderr__.fileno(), sys.__stdout__.fileno())

    try:
        for hname, cmd in ui.configitems('hooks'):
            if hname.split('.')[0] != name or not cmd:
                continue
            if hasattr(cmd, '__call__'):
                r = _pythonhook(ui, repo, name, hname, cmd, args, throw) or r
            elif cmd.startswith('python:'):
                if cmd.count(':') == 2:
                    path, cmd = cmd[7:].split(':')
                    mod = extensions.loadpath(path, 'hgkook.%s' % hname)
                    hookfn = getattr(mod, cmd)
                else:
                    hookfn = cmd[7:].strip()
                r = _pythonhook(ui, repo, name, hname, hookfn, args, throw) or r
            else:
                r = _exthook(ui, repo, hname, cmd, args, throw) or r
    finally:
        if _redirect:
            os.dup2(oldstdout, sys.__stdout__.fileno())
            os.close(oldstdout)

    return r