~bzr-pqm/bzr/bzr.dev

1 by mbp at sourcefrog
import from baz patch-364
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# -*- coding: UTF-8 -*-
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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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# 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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# 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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"""XML externalization support."""
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48 by Martin Pool
witty comment
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# "XML is like violence: if it doesn't solve your problem, you aren't
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# using enough of it." -- various
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1180 by Martin Pool
- start splitting code for xml (de)serialization away from objects
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# importing this module is fairly slow because it has to load several
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# ElementTree bits
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1248 by Martin Pool
- new weave based cleanup [broken]
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from bzrlib.trace import mutter, warning
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802 by Martin Pool
- Remove XMLMixin class in favour of simple pack_xml, unpack_xml functions
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try:
1283 by Martin Pool
- cElementTree is typically not installed in util
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    from cElementTree import (ElementTree, SubElement, Element,
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                              XMLTreeBuilder, fromstring, tostring)
802 by Martin Pool
- Remove XMLMixin class in favour of simple pack_xml, unpack_xml functions
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except ImportError:
1390 by Robert Collins
pair programming worx... merge integration and weave
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    ## from warnings import warn
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    ## warn('using slower ElementTree; consider installing cElementTree')
1227 by Martin Pool
- methods to deserialize objects from strings
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    from util.elementtree.ElementTree import (ElementTree, SubElement,
1248 by Martin Pool
- new weave based cleanup [broken]
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                                              Element, XMLTreeBuilder,
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                                              fromstring, tostring)
802 by Martin Pool
- Remove XMLMixin class in favour of simple pack_xml, unpack_xml functions
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1183 by Martin Pool
- implement version 5 xml storage, and tests
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from bzrlib.errors import BzrError
1180 by Martin Pool
- start splitting code for xml (de)serialization away from objects
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class Serializer(object):
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    """Abstract object serialize/deserialize"""
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    def write_inventory(self, inv, f):
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        """Write inventory to a file"""
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        elt = self._pack_inventory(inv)
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        self._write_element(elt, f)
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1248 by Martin Pool
- new weave based cleanup [broken]
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    def write_inventory_to_string(self, inv):
1185.16.123 by Martin Pool
Fix syntax of serializer_v5.pack_revision_to_string
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        return tostring(self._pack_inventory(inv)) + '\n'
1248 by Martin Pool
- new weave based cleanup [broken]
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1227 by Martin Pool
- methods to deserialize objects from strings
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    def read_inventory_from_string(self, xml_string):
1248 by Martin Pool
- new weave based cleanup [broken]
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        return self._unpack_inventory(fromstring(xml_string))
1227 by Martin Pool
- methods to deserialize objects from strings
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1180 by Martin Pool
- start splitting code for xml (de)serialization away from objects
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    def read_inventory(self, f):
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        return self._unpack_inventory(self._read_element(f))
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1182 by Martin Pool
- more disentangling of xml storage format from objects
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    def write_revision(self, rev, f):
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        self._write_element(self._pack_revision(rev), f)
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1248 by Martin Pool
- new weave based cleanup [broken]
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    def write_revision_to_string(self, rev):
1185.16.123 by Martin Pool
Fix syntax of serializer_v5.pack_revision_to_string
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        return tostring(self._pack_revision(rev)) + '\n'
1248 by Martin Pool
- new weave based cleanup [broken]
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1182 by Martin Pool
- more disentangling of xml storage format from objects
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    def read_revision(self, f):
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        return self._unpack_revision(self._read_element(f))
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1227 by Martin Pool
- methods to deserialize objects from strings
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    def read_revision_from_string(self, xml_string):
1248 by Martin Pool
- new weave based cleanup [broken]
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        return self._unpack_revision(fromstring(xml_string))
1227 by Martin Pool
- methods to deserialize objects from strings
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1180 by Martin Pool
- start splitting code for xml (de)serialization away from objects
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    def _write_element(self, elt, f):
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        ElementTree(elt).write(f, 'utf-8')
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        f.write('\n')
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    def _read_element(self, f):
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        return ElementTree().parse(f)