view mercurial/error.py @ 20713:6a1a4c212d50

revset: improve head revset performance

Previously the head() revset would iterate over every item in the subset and
check if it was a head.  Since the subset is often the entire repo, this was
slow on large repos. Now we iterate over each item in the head list and check if
it's in the subset, which results in much less work.

hg log -r 'head()' on a large repo:
Before: 0.95s
After: 0.28s

# error.py - Mercurial exceptions
#
# Copyright 2005-2008 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.

"""Mercurial exceptions.

This allows us to catch exceptions at higher levels without forcing
imports.
"""

# Do not import anything here, please

class RevlogError(Exception):
    pass

class LookupError(RevlogError, KeyError):
    def __init__(self, name, index, message):
        self.name = name
        if isinstance(name, str) and len(name) == 20:
            from node import short
            name = short(name)
        RevlogError.__init__(self, '%s@%s: %s' % (index, name, message))

    def __str__(self):
        return RevlogError.__str__(self)

class ManifestLookupError(LookupError):
    pass

class CommandError(Exception):
    """Exception raised on errors in parsing the command line."""

class InterventionRequired(Exception):
    """Exception raised when a command requires human intervention."""

class Abort(Exception):
    """Raised if a command needs to print an error and exit."""
    def __init__(self, *args, **kw):
        Exception.__init__(self, *args)
        self.hint = kw.get('hint')

class ConfigError(Abort):
    'Exception raised when parsing config files'

class OutOfBandError(Exception):
    'Exception raised when a remote repo reports failure'

class ParseError(Exception):
    'Exception raised when parsing config files (msg[, pos])'

class RepoError(Exception):
    def __init__(self, *args, **kw):
        Exception.__init__(self, *args)
        self.hint = kw.get('hint')

class RepoLookupError(RepoError):
    pass

class CapabilityError(RepoError):
    pass

class RequirementError(RepoError):
    """Exception raised if .hg/requires has an unknown entry."""
    pass

class LockError(IOError):
    def __init__(self, errno, strerror, filename, desc):
        IOError.__init__(self, errno, strerror, filename)
        self.desc = desc

class LockHeld(LockError):
    def __init__(self, errno, filename, desc, locker):
        LockError.__init__(self, errno, 'Lock held', filename, desc)
        self.locker = locker

class LockUnavailable(LockError):
    pass

class ResponseError(Exception):
    """Raised to print an error with part of output and exit."""

class UnknownCommand(Exception):
    """Exception raised if command is not in the command table."""

class AmbiguousCommand(Exception):
    """Exception raised if command shortcut matches more than one command."""

# derived from KeyboardInterrupt to simplify some breakout code
class SignalInterrupt(KeyboardInterrupt):
    """Exception raised on SIGTERM and SIGHUP."""

class SignatureError(Exception):
    pass