~bzr-pqm/bzr/bzr.dev

# -*- coding: UTF-8 -*-

# This program is free software; you can redistribute it and/or modify

# it under the terms of the GNU General Public License as published by

# the Free Software Foundation; either version 2 of the License, or

# (at your option) any later version.

# This program is distributed in the hope that it will be useful,

# but WITHOUT ANY WARRANTY; without even the implied warranty of

# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

# GNU General Public License for more details.

# You should have received a copy of the GNU General Public License

# along with this program; if not, write to the Free Software

# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA

"""Exceptions for bzr, and reporting of them.

Exceptions are caught at a high level to report errors to the user, and

might also be caught inside the program.  Therefore it needs to be

possible to convert them to a meaningful string, and also for them to be

interrogated by the program.

Exceptions are defined such that the arguments given to the constructor

are stored in the object as properties of the same name.  When the

object is printed as a string, the doc string of the class is used as

a format string with the property dictionary available to it.

This means that exceptions can used like this:

>>> import sys

>>> try:

...   raise NotBranchError(path='/foo/bar')

... except:

...   print sys.exc_type

...   print sys.exc_value

...   print sys.exc_value.path

bzrlib.errors.NotBranchError

Not a branch: /foo/bar

/foo/bar

Therefore:

 * create a new exception class for any class of error that can be

   usefully distinguished.

 * the printable form of an exception is generated by the base class

   __str__ method

"""

# based on Scott James Remnant's hct error classes

# TODO: is there any value in providing the .args field used by standard

# python exceptions?   A list of values with no names seems less useful 

# to me.

# TODO: Perhaps convert the exception to a string at the moment it's 

# constructed to make sure it will succeed.  But that says nothing about

# exceptions that are never raised.

# TODO: Convert all the other error classes here to BzrNewError, and eliminate

# the old one.

class BzrError(StandardError):

    def __str__(self):

        # XXX: Should we show the exception class in 

        # exceptions that don't provide their own message?  

        # maybe it should be done at a higher level

        ## n = self.__class__.__name__ + ': '

        n = ''

        if len(self.args) == 1:

            return str(self.args[0])

        elif len(self.args) == 2:

            # further explanation or suggestions

            try:

                return n + '\n  '.join([self.args[0]] + self.args[1])

            except TypeError:

                return n + "%r" % self

        else:

            return n + `self.args`

class BzrNewError(BzrError):

    """bzr error"""

    # base classes should override the docstring with their human-

    # readable explanation

    def __init__(self, **kwds):

        for key, value in kwds.items():

            setattr(self, key, value)

    def __str__(self):

        try:

            return self.__doc__ % self.__dict__

        except (NameError, ValueError, KeyError), e:

            return 'Unprintable exception %s: %s' \

                % (self.__class__.__name__, str(e))

class BzrCheckError(BzrNewError):

    """Internal check failed: %(message)s"""

    def __init__(self, message):

        self.message = message

class InvalidEntryName(BzrNewError):

    """Invalid entry name: %(name)s"""

    def __init__(self, name):

        self.name = name

class InvalidRevisionNumber(BzrNewError):

    """Invalid revision number %(revno)d"""

    def __init__(self, revno):

        self.revno = revno

class InvalidRevisionId(BzrNewError):

    """Invalid revision-id"""

class BzrCommandError(BzrError):

    # Error from malformed user command

    def __str__(self):

        return self.args[0]

class StrictCommitFailed(Exception):

    """Commit refused because there are unknowns in the tree."""

class NotBranchError(BzrNewError):

    """Not a branch: %(path)s"""

    def __init__(self, path):

        BzrNewError.__init__(self)

        self.path = path

class UnsupportedFormatError(BzrError):

    """Specified path is a bzr branch that we cannot read."""

    def __str__(self):

        return 'unsupported branch format: %s' % self.args[0]

class NotVersionedError(BzrNewError):

    """%(path)s is not versioned"""

    def __init__(self, path):

        BzrNewError.__init__(self)

        self.path = path

class BadFileKindError(BzrError):

    """Specified file is of a kind that cannot be added.

    (For example a symlink or device file.)"""

class ForbiddenFileError(BzrError):

    """Cannot operate on a file because it is a control file."""

class LockError(Exception):

    """Lock error"""

    # All exceptions from the lock/unlock functions should be from

    # this exception class.  They will be translated as necessary. The

    # original exception is available as e.original_error

class CommitNotPossible(LockError):

    """A commit was attempted but we do not have a write lock open."""

class AlreadyCommitted(LockError):

    """A rollback was requested, but is not able to be accomplished."""

class ReadOnlyError(LockError):

    """A write attempt was made in a read only transaction."""

class PointlessCommit(BzrNewError):

    """No changes to commit"""

class NoSuchRevision(BzrError):

    def __init__(self, branch, revision):

        self.branch = branch

        self.revision = revision

        msg = "Branch %s has no revision %s" % (branch, revision)

        BzrError.__init__(self, msg)

class HistoryMissing(BzrError):

    def __init__(self, branch, object_type, object_id):

        self.branch = branch

        BzrError.__init__(self,

                          '%s is missing %s {%s}'

                          % (branch, object_type, object_id))

class DivergedBranches(BzrError):

    def __init__(self, branch1, branch2):

        BzrError.__init__(self, "These branches have diverged.")

        self.branch1 = branch1

        self.branch2 = branch2

class UnrelatedBranches(BzrCommandError):

    def __init__(self):

        msg = "Branches have no common ancestor, and no base revision"\

            " specified."

        BzrCommandError.__init__(self, msg)

class NoCommonAncestor(BzrError):

    def __init__(self, revision_a, revision_b):

        msg = "Revisions have no common ancestor: %s %s." \

            % (revision_a, revision_b) 

        BzrError.__init__(self, msg)

class NoCommonRoot(BzrError):

    def __init__(self, revision_a, revision_b):

        msg = "Revisions are not derived from the same root: %s %s." \

            % (revision_a, revision_b) 

        BzrError.__init__(self, msg)

class NotAncestor(BzrError):

    def __init__(self, rev_id, not_ancestor_id):

        msg = "Revision %s is not an ancestor of %s" % (not_ancestor_id, 

                                                        rev_id)

        BzrError.__init__(self, msg)

        self.rev_id = rev_id

        self.not_ancestor_id = not_ancestor_id

class NotAncestor(BzrError):

    def __init__(self, rev_id, not_ancestor_id):

        self.rev_id = rev_id

        self.not_ancestor_id = not_ancestor_id

        msg = "Revision %s is not an ancestor of %s" % (not_ancestor_id, 

                                                        rev_id)

        BzrError.__init__(self, msg)

class InstallFailed(BzrError):

    def __init__(self, revisions):

        msg = "Could not install revisions:\n%s" % " ,".join(revisions)

        BzrError.__init__(self, msg)

        self.revisions = revisions

class AmbiguousBase(BzrError):

    def __init__(self, bases):

        msg = "The correct base is unclear, becase %s are all equally close" %\

            ", ".join(bases)

        BzrError.__init__(self, msg)

        self.bases = bases

class NoCommits(BzrError):

    def __init__(self, branch):

        msg = "Branch %s has no commits." % branch

        BzrError.__init__(self, msg)

class UnlistableStore(BzrError):

    def __init__(self, store):

        BzrError.__init__(self, "Store %s is not listable" % store)

class UnlistableBranch(BzrError):

    def __init__(self, br):

        BzrError.__init__(self, "Stores for branch %s are not listable" % br)

from bzrlib.weave import WeaveError, WeaveParentMismatch

class TransportError(BzrError):

    """All errors thrown by Transport implementations should derive

    from this class.

    """

    def __init__(self, msg=None, orig_error=None):

        if msg is None and orig_error is not None:

            msg = str(orig_error)

        BzrError.__init__(self, msg)

        self.msg = msg

        self.orig_error = orig_error

# A set of semi-meaningful errors which can be thrown

class TransportNotPossible(TransportError):

    """This is for transports where a specific function is explicitly not

    possible. Such as pushing files to an HTTP server.

    """

    pass

class NonRelativePath(TransportError):

    """An absolute path was supplied, that could not be decoded into

    a relative path.

    """

    pass

class NoSuchFile(TransportError, IOError):

    """A get() was issued for a file that doesn't exist."""

    # XXX: Is multiple inheritance for exceptions really needed?

    def __str__(self):

        return 'no such file: ' + self.msg

    def __init__(self, msg=None, orig_error=None):

        import errno

        TransportError.__init__(self, msg=msg, orig_error=orig_error)

        IOError.__init__(self, errno.ENOENT, self.msg)

class FileExists(TransportError, OSError):

    """An operation was attempted, which would overwrite an entry,

    but overwritting is not supported.

    mkdir() can throw this, but put() just overwites existing files.

    """

    # XXX: Is multiple inheritance for exceptions really needed?

    def __init__(self, msg=None, orig_error=None):

        import errno

        TransportError.__init__(self, msg=msg, orig_error=orig_error)

        OSError.__init__(self, errno.EEXIST, self.msg)

class PermissionDenied(TransportError):

    """An operation cannot succeed because of a lack of permissions."""

    pass

class ConnectionReset(TransportError):

    """The connection has been closed."""

    pass

class ConflictsInTree(BzrError):

    def __init__(self):

        BzrError.__init__(self, "Working tree has conflicts.")

class SigningFailed(BzrError):

    def __init__(self, command_line):

        BzrError.__init__(self, "Failed to gpg sign data with command '%s'"

                               % command_line)