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2052.3.2
by John Arbash Meinel
Change Copyright .. by Canonical to Copyright ... Canonical |
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# Copyright (C) 2005 Canonical Ltd
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1417.1.6
by Robert Collins
introduce transactions for grouping actions done to and with branches |
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# Authors: Robert Collins <robert.collins@canonical.com>
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#
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# This program is free software; you can redistribute it and/or modify
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# it under the terms of the GNU General Public License as published by
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# the Free Software Foundation; either version 2 of the License, or
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# (at your option) any later version.
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#
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# This program is distributed in the hope that it will be useful,
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# but WITHOUT ANY WARRANTY; without even the implied warranty of
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# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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# GNU General Public License for more details.
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#
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# You should have received a copy of the GNU General Public License
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# along with this program; if not, write to the Free Software
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# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
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"""This module provides an IdentityMap."""
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2294.1.10
by John Arbash Meinel
Switch all apis over to utf8 file ids. All tests pass |
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from bzrlib import ( |
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errors, |
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osutils, |
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)
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1417.1.6
by Robert Collins
introduce transactions for grouping actions done to and with branches |
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class IdentityMap(object): |
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"""An in memory map from object id to instance.
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An IdentityMap maps from keys to single instances of objects in memory.
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We have explicit calls on the map for the root of each inheritance tree
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that is store in the map. Look for find_CLASS and add_CLASS methods.
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"""
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def add_weave(self, id, weave): |
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"""Add weave to the map with a given id."""
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if self._weave_key(id) in self._map: |
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raise errors.BzrError('weave %s already in the identity map' % id) |
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self._map[self._weave_key(id)] = weave |
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1417.1.10
by Robert Collins
add a cache bound to Transactions, and a precious facility, so that we keep inventory.weave in memory, but can discard weaves for other such files. |
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self._reverse_map[weave] = self._weave_key(id) |
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1417.1.6
by Robert Collins
introduce transactions for grouping actions done to and with branches |
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def find_weave(self, id): |
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"""Return the weave for 'id', or None if it is not present."""
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return self._map.get(self._weave_key(id), None) |
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def __init__(self): |
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super(IdentityMap, self).__init__() |
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self._map = {} |
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1417.1.10
by Robert Collins
add a cache bound to Transactions, and a precious facility, so that we keep inventory.weave in memory, but can discard weaves for other such files. |
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self._reverse_map = {} |
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def remove_object(self, an_object): |
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1417.1.12
by Robert Collins
cache revision history during read transactions |
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"""Remove object from map."""
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if isinstance(an_object, list): |
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2375.1.5
by Andrew Bennetts
Deal with review comments from Robert: |
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raise KeyError('%r not in identity map' % an_object) |
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1417.1.12
by Robert Collins
cache revision history during read transactions |
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else: |
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1417.1.10
by Robert Collins
add a cache bound to Transactions, and a precious facility, so that we keep inventory.weave in memory, but can discard weaves for other such files. |
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self._map.pop(self._reverse_map[an_object]) |
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self._reverse_map.pop(an_object) |
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1417.1.6
by Robert Collins
introduce transactions for grouping actions done to and with branches |
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def _weave_key(self, id): |
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"""Return the key for a weaves id."""
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return "weave-" + id |
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class NullIdentityMap(object): |
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"""A pretend in memory map from object id to instance.
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A NullIdentityMap is an Identity map that does not store anything in it.
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"""
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def add_weave(self, id, weave): |
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"""See IdentityMap.add_weave."""
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def find_weave(self, id): |
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"""See IdentityMap.find_weave."""
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return None |