view mercurial/hook.py @ 25878:800e090e9c64 stable

localrepo: make journal.dirstate contain in-memory changes before transaction

Before this patch, in-memory dirstate changes aren't written out at
opening transaction, even though 'journal.dirstate' is created
directly from '.hg/dirstate'.

Therefore, subsequent 'hg rollback' uses incomplete 'undo.dirstate' to
restore dirstate, if dirstate is changed and isn't written out before
opening transaction.

In cases below, the condition "dirstate is changed and isn't written
out before opening transaction" isn't satisfied and this problem
doesn't appear:

  - "wlock scope" and "transaction scope" are almost equivalent

    e.g. 'commit --amend', 'import' and so on

  - dirstate changes are written out before opening transaction

    e.g. 'rebase' (via 'dirstateguard') and 'commit -A' (by separated
    wlock scopes)

On the other hand, 'backout' may satisfy the condition above.

To make 'journal.dirstate' contain in-memory changes before opening
transaction, this patch explicitly invokes 'dirstate.write()' in
'localrepository.transaction()'.

'dirstate.write()' is placed before not "writing journal files out"
but "invoking pretxnopen hooks" for visibility of dirstate changes to
external hook processes.

BTW, in the test script, 'touch -t 200001010000' and 'hg status' are
invoked to make file 'c' surely clean in dirstate, because "clean but
unsure" files indirectly cause 'dirstate.write()' at 'repo.status()'
in 'repo.commit()' (see fe03f522dda9 for detail) and prevents from
certainly reproducing the issue.

# 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 or any later version.

from i18n import _
import os, sys, time
import extensions, util, demandimport, error

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.'''

    if callable(funcname):
        obj = funcname
        funcname = obj.__module__ + "." + obj.__name__
    else:
        d = funcname.rfind('.')
        if d == -1:
            raise util.Abort(_('%s hook is invalid ("%s" not in '
                               'a module)') % (hname, funcname))
        modname = funcname[:d]
        oldpaths = sys.path
        if util.mainfrozen():
            # binary installs require sys.path manipulation
            modpath, modfile = os.path.split(modname)
            if modpath and modfile:
                sys.path = sys.path[:] + [modpath]
                modname = modfile
        with demandimport.deactivated():
            try:
                obj = __import__(modname)
            except ImportError:
                e1 = sys.exc_type, sys.exc_value, sys.exc_traceback
                try:
                    # extensions are loaded with hgext_ prefix
                    obj = __import__("hgext_%s" % modname)
                except ImportError:
                    e2 = sys.exc_type, sys.exc_value, sys.exc_traceback
                    if ui.tracebackflag:
                        ui.warn(_('exception from first failed import '
                                  'attempt:\n'))
                    ui.traceback(e1)
                    if ui.tracebackflag:
                        ui.warn(_('exception from second failed import '
                                  'attempt:\n'))
                    ui.traceback(e2)
                    raise util.Abort(_('%s hook is invalid '
                                       '(import of "%s" failed)') %
                                     (hname, modname))
        sys.path = oldpaths
        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 callable(obj):
            raise util.Abort(_('%s hook is invalid '
                               '("%s" is not callable)') %
                             (hname, funcname))

    ui.note(_("calling hook %s: %s\n") % (hname, funcname))
    starttime = time.time()

    try:
        # redirect IO descriptors to the ui descriptors so hooks
        # that write directly to these don't mess up the command
        # protocol when running through the command server
        old = sys.stdout, sys.stderr, sys.stdin
        sys.stdout, sys.stderr, sys.stdin = ui.fout, ui.ferr, ui.fin

        r = obj(ui=ui, repo=repo, hooktype=name, **args)
    except Exception as 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
    finally:
        sys.stdout, sys.stderr, sys.stdin = old
        duration = time.time() - starttime
        ui.log('pythonhook', 'pythonhook-%s: %s finished in %0.2f seconds\n',
               name, funcname, duration)
    if r:
        if throw:
            raise error.HookAbort(_('%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))

    starttime = time.time()
    env = {}
    for k, v in args.iteritems():
        if callable(v):
            v = v()
        if isinstance(v, dict):
            # make the dictionary element order stable across Python
            # implementations
            v = ('{' +
                 ', '.join('%r: %r' % i for i in sorted(v.iteritems())) +
                 '}')
        env['HG_' + k.upper()] = v

    if repo:
        cwd = repo.root
    else:
        cwd = os.getcwd()
    r = ui.system(cmd, environ=env, cwd=cwd)

    duration = time.time() - starttime
    ui.log('exthook', 'exthook-%s: %s finished in %0.2f seconds\n',
           name, cmd, duration)
    if r:
        desc, r = util.explainexit(r)
        if throw:
            raise error.HookAbort(_('%s hook %s') % (name, desc))
        ui.warn(_('warning: %s hook %s\n') % (name, desc))
    return r

def _allhooks(ui):
    hooks = []
    for name, cmd in ui.configitems('hooks'):
        if not name.startswith('priority'):
            priority = ui.configint('hooks', 'priority.%s' % name, 0)
            hooks.append((-priority, len(hooks), name, cmd))
    return [(k, v) for p, o, k, v in sorted(hooks)]

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

def hook(ui, repo, name, throw=False, **args):
    if not ui.callhooks:
        return False

    r = False
    oldstdout = -1

    try:
        for hname, cmd in _allhooks(ui):
            if hname.split('.')[0] != name or not cmd:
                continue

            if oldstdout == -1 and _redirect:
                try:
                    stdoutno = sys.__stdout__.fileno()
                    stderrno = sys.__stderr__.fileno()
                    # temporarily redirect stdout to stderr, if possible
                    if stdoutno >= 0 and stderrno >= 0:
                        sys.__stdout__.flush()
                        oldstdout = os.dup(stdoutno)
                        os.dup2(stderrno, stdoutno)
                except (OSError, AttributeError):
                    # files seem to be bogus, give up on redirecting (WSGI, etc)
                    pass

            if callable(cmd):
                r = _pythonhook(ui, repo, name, hname, cmd, args, throw) or r
            elif cmd.startswith('python:'):
                if cmd.count(':') >= 2:
                    path, cmd = cmd[7:].rsplit(':', 1)
                    path = util.expandpath(path)
                    if repo:
                        path = os.path.join(repo.root, path)
                    try:
                        mod = extensions.loadpath(path, 'hghook.%s' % hname)
                    except Exception:
                        ui.write(_("loading %s hook failed:\n") % hname)
                        raise
                    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

            # The stderr is fully buffered on Windows when connected to a pipe.
            # A forcible flush is required to make small stderr data in the
            # remote side available to the client immediately.
            sys.stderr.flush()
    finally:
        if _redirect and oldstdout >= 0:
            os.dup2(oldstdout, stdoutno)
            os.close(oldstdout)

    return r