mercurial/error.py

revset: add origin() predicate

This predicate is used to find the original source of csets created by a graft,
transplant or rebase --keep.  If a copied cset is itself copied, only the
source of the original copy is selected.

    hg log -r origin()                # all src csets, anywhere
    hg log -r origin(branch(default)) # all srcs of copies on default

By following through different types of copy commands and only selecting the
original cset, the implementation differences between the copy commands are
hidden.  (A graft of a graft preserves the original source in its 'extra' map,
while transplant and rebase use the immediate source specified for the
command).

Given a repo with a cset S that is grafted to create G(S), which itself is
grafted to become G(G(S))

    o-S
   /
  o-o-G(S)
   \
    o-G(G(S))

    hg log -r origin( G(S) )      # { S }
    hg log -r origin( G(G(S)) )   # { S }, NOT { G(S) }

Even if the last graft were a transplant

    hg log -r origin( T(G(S)) )   # { S }

A rebase without --keep essentially strips the source, so providing the cset
that results to this predicate will yield an empty set.

Note that the convert extension does not currently update the 'extra' map in
its destination csets, and therefore copies made prior to the convert will be
unable to find their source.

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

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