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# Copyright (C) 2007, 2008 Canonical Ltd
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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., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
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"""Python implementations of Dirstate Helper functions."""
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from __future__ import absolute_import
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# We cannot import the dirstate module, because it loads this module
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# All we really need is the IN_MEMORY_MODIFIED constant
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from bzrlib import errors
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from bzrlib.dirstate import DirState
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def pack_stat(st, _b64=binascii.b2a_base64, _pack=struct.Struct('>6L').pack):
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"""Convert stat values into a packed representation
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Not all of the fields from the stat included are strictly needed, and by
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just encoding the mtime and mode a slight speed increase could be gained.
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However, using the pyrex version instead is a bigger win.
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# base64 encoding always adds a final newline, so strip it off
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return _b64(_pack(st.st_size & 0xFFFFFFFF, int(st.st_mtime) & 0xFFFFFFFF,
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int(st.st_ctime) & 0xFFFFFFFF, st.st_dev & 0xFFFFFFFF,
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st.st_ino & 0xFFFFFFFF, st.st_mode))[:-1]
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def _unpack_stat(packed_stat):
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"""Turn a packed_stat back into the stat fields.
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This is meant as a debugging tool, should not be used in real code.
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(st_size, st_mtime, st_ctime, st_dev, st_ino,
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st_mode) = struct.unpack('>6L', binascii.a2b_base64(packed_stat))
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return dict(st_size=st_size, st_mtime=st_mtime, st_ctime=st_ctime,
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st_dev=st_dev, st_ino=st_ino, st_mode=st_mode)
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def _bisect_path_left(paths, path):
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"""Return the index where to insert path into paths.
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This uses the dirblock sorting. So all children in a directory come before
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the children of children. For example::
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:param paths: A list of paths to search through
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:param path: A single path to insert
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:return: An offset where 'path' can be inserted.
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:seealso: bisect.bisect_left
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# Grab the dirname for the current dirblock
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if _cmp_path_by_dirblock(cur, path) < 0:
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def _bisect_path_right(paths, path):
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"""Return the index where to insert path into paths.
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This uses a path-wise comparison so we get::
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:param paths: A list of paths to search through
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:param path: A single path to insert
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:return: An offset where 'path' can be inserted.
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:seealso: bisect.bisect_right
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# Grab the dirname for the current dirblock
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if _cmp_path_by_dirblock(path, cur) < 0:
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def bisect_dirblock(dirblocks, dirname, lo=0, hi=None, cache={}):
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"""Return the index where to insert dirname into the dirblocks.
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The return value idx is such that all directories blocks in dirblock[:idx]
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have names < dirname, and all blocks in dirblock[idx:] have names >=
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Optional args lo (default 0) and hi (default len(dirblocks)) bound the
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slice of a to be searched.
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dirname_split = cache[dirname]
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dirname_split = dirname.split('/')
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cache[dirname] = dirname_split
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# Grab the dirname for the current dirblock
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cur = dirblocks[mid][0]
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cur_split = cache[cur]
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cur_split = cur.split('/')
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cache[cur] = cur_split
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if cur_split < dirname_split: lo = mid + 1
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def cmp_by_dirs(path1, path2):
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"""Compare two paths directory by directory.
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This is equivalent to doing::
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cmp(path1.split('/'), path2.split('/'))
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The idea is that you should compare path components separately. This
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differs from plain ``cmp(path1, path2)`` for paths like ``'a-b'`` and
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``a/b``. "a-b" comes after "a" but would come before "a/b" lexically.
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:param path1: first path
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:param path2: second path
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:return: negative number if ``path1`` comes first,
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0 if paths are equal,
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and positive number if ``path2`` sorts first
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if not isinstance(path1, str):
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raise TypeError("'path1' must be a plain string, not %s: %r"
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% (type(path1), path1))
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if not isinstance(path2, str):
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raise TypeError("'path2' must be a plain string, not %s: %r"
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% (type(path2), path2))
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return cmp(path1.split('/'), path2.split('/'))
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def _cmp_path_by_dirblock(path1, path2):
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"""Compare two paths based on what directory they are in.
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This generates a sort order, such that all children of a directory are
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sorted together, and grandchildren are in the same order as the
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children appear. But all grandchildren come after all children.
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:param path1: first path
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:param path2: the second path
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:return: negative number if ``path1`` comes first,
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and a positive number if ``path2`` sorts first
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if not isinstance(path1, str):
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raise TypeError("'path1' must be a plain string, not %s: %r"
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% (type(path1), path1))
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if not isinstance(path2, str):
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raise TypeError("'path2' must be a plain string, not %s: %r"
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% (type(path2), path2))
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dirname1, basename1 = os.path.split(path1)
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key1 = (dirname1.split('/'), basename1)
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dirname2, basename2 = os.path.split(path2)
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key2 = (dirname2.split('/'), basename2)
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return cmp(key1, key2)
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def _read_dirblocks(state):
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"""Read in the dirblocks for the given DirState object.
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This is tightly bound to the DirState internal representation. It should be
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thought of as a member function, which is only separated out so that we can
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re-write it in pyrex.
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:param state: A DirState object.
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state._state_file.seek(state._end_of_header)
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text = state._state_file.read()
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# TODO: check the crc checksums. crc_measured = zlib.crc32(text)
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fields = text.split('\0')
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# Remove the last blank entry
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trailing = fields.pop()
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raise errors.DirstateCorrupt(state,
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'trailing garbage: %r' % (trailing,))
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# consider turning fields into a tuple.
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# skip the first field which is the trailing null from the header.
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# Each line now has an extra '\n' field which is not used
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# so we just skip over it
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# 3 fields for the key
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# + number of fields per tree_data (5) * tree count
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num_present_parents = state._num_present_parents()
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tree_count = 1 + num_present_parents
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entry_size = state._fields_per_entry()
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expected_field_count = entry_size * state._num_entries
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field_count = len(fields)
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# this checks our adjustment, and also catches file too short.
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if field_count - cur != expected_field_count:
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raise errors.DirstateCorrupt(state,
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'field count incorrect %s != %s, entry_size=%s, '\
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'num_entries=%s fields=%r' % (
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field_count - cur, expected_field_count, entry_size,
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state._num_entries, fields))
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if num_present_parents == 1:
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# Bind external functions to local names
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# We access all fields in order, so we can just iterate over
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# them. Grab an straight iterator over the fields. (We use an
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# iterator because we don't want to do a lot of additions, nor
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# do we want to do a lot of slicing)
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next = iter(fields).next
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# Move the iterator to the current position
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for x in xrange(cur):
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# The two blocks here are deliberate: the root block and the
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# contents-of-root block.
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state._dirblocks = [('', []), ('', [])]
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current_block = state._dirblocks[0][1]
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append_entry = current_block.append
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for count in xrange(state._num_entries):
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if dirname != current_dirname:
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# new block - different dirname
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current_dirname = dirname
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state._dirblocks.append((current_dirname, current_block))
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append_entry = current_block.append
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# we know current_dirname == dirname, so re-use it to avoid
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# creating new strings
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entry = ((current_dirname, name, file_id),
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next(), # fingerprint
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next() == 'y', # executable
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next(), # packed_stat or revision_id
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next(), # fingerprint
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next() == 'y', # executable
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next(), # packed_stat or revision_id
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raise ValueError("trailing garbage in dirstate: %r" % trailing)
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# append the entry to the current block
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state._split_root_dirblock_into_contents()
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fields_to_entry = state._get_fields_to_entry()
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entries = [fields_to_entry(fields[pos:pos+entry_size])
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for pos in xrange(cur, field_count, entry_size)]
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state._entries_to_current_state(entries)
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# To convert from format 2 => format 3
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# state._dirblocks = sorted(state._dirblocks,
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# key=lambda blk:blk[0].split('/'))
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# To convert from format 3 => format 2
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# state._dirblocks = sorted(state._dirblocks)
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state._dirblock_state = DirState.IN_MEMORY_UNMODIFIED