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# -*- coding: UTF-8 -*-
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# (C) 2005 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
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"""Inventories map files to their name in a revision."""
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__copyright__ = "Copyright (C) 2005 Canonical Ltd."
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__author__ = "Martin Pool <mbp@canonical.com>"
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import sys, os.path, types
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from cElementTree import Element, ElementTree, SubElement
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from elementtree.ElementTree import Element, ElementTree, SubElement
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from xml import XMLMixin
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from errors import bailout
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from osutils import uuid, quotefn, splitpath, joinpath, appendpath
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from trace import mutter
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class InventoryEntry(XMLMixin):
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# TODO: Maybe also keep the full path of the entry, and the children?
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# But those depend on its position within a particular inventory, and
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# it would be nice not to need to hold the backpointer here.
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# This should really be an id randomly assigned when the tree is
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# created, but it's not for now.
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from bzrlib.errors import BzrError, BzrCheckError
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from bzrlib.osutils import (pumpfile, quotefn, splitpath, joinpath,
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appendpath, sha_strings)
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from bzrlib.trace import mutter
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from bzrlib.errors import NotVersionedError
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class InventoryEntry(object):
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"""Description of a versioned file.
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An InventoryEntry has the following fields, which are also
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present in the XML inventory-entry element:
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* *name*: (only the basename within the directory, must not
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* *kind*: "directory" or "file"
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* *directory_id*: (if absent/null means the branch root directory)
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* *text_sha1*: only for files
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* *text_size*: in bytes, only for files
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* *text_id*: identifier for the text version, only for files
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InventoryEntries can also exist inside a WorkingTree
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inventory, in which case they are not yet bound to a
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particular revision of the file. In that case the text_sha1,
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text_size and text_id are absent.
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(within the parent directory)
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file_id of the parent directory, or ROOT_ID
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the revision_id in which this variation of this file was
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Indicates that this file should be executable on systems
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sha-1 of the text of the file
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size in bytes of the text of the file
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(reading a version 4 tree created a text_id field.)
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>>> i = Inventory()
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>>> i.add(InventoryEntry('123', 'src', kind='directory'))
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>>> i.add(InventoryEntry('2323', 'hello.c', parent_id='123'))
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>>> i.add(InventoryDirectory('123', 'src', ROOT_ID))
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InventoryDirectory('123', 'src', parent_id='TREE_ROOT')
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>>> i.add(InventoryFile('2323', 'hello.c', parent_id='123'))
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InventoryFile('2323', 'hello.c', parent_id='123')
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>>> for j in i.iter_entries():
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('src', InventoryEntry('123', 'src', kind='directory', parent_id=None))
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('src/hello.c', InventoryEntry('2323', 'hello.c', kind='file', parent_id='123'))
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>>> i.add(InventoryEntry('2323', 'bye.c', parent_id='123'))
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('src', InventoryDirectory('123', 'src', parent_id='TREE_ROOT'))
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('src/hello.c', InventoryFile('2323', 'hello.c', parent_id='123'))
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>>> i.add(InventoryFile('2323', 'bye.c', '123'))
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Traceback (most recent call last):
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BzrError: ('inventory already contains entry with id {2323}', [])
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>>> i.add(InventoryEntry('2324', 'bye.c', parent_id='123'))
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>>> i.add(InventoryEntry('2325', 'wibble', parent_id='123', kind='directory'))
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BzrError: inventory already contains entry with id {2323}
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>>> i.add(InventoryFile('2324', 'bye.c', '123'))
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InventoryFile('2324', 'bye.c', parent_id='123')
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>>> i.add(InventoryDirectory('2325', 'wibble', '123'))
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InventoryDirectory('2325', 'wibble', parent_id='123')
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>>> i.path2id('src/wibble')
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>>> i.add(InventoryEntry('2326', 'wibble.c', parent_id='2325'))
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>>> i.add(InventoryFile('2326', 'wibble.c', '2325'))
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InventoryFile('2326', 'wibble.c', parent_id='2325')
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InventoryEntry('2326', 'wibble.c', kind='file', parent_id='2325')
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>>> for j in i.iter_entries():
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... assert i.path2id(j[0])
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InventoryFile('2326', 'wibble.c', parent_id='2325')
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>>> for path, entry in i.iter_entries():
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... print path.replace('\\\\', '/') # for win32 os.sep
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... assert i.path2id(path)
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src/wibble/wibble.c
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>>> i.id2path('2326').replace('\\\\', '/')
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'src/wibble/wibble.c'
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:todo: Maybe also keep the full path of the entry, and the children?
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But those depend on its position within a particular inventory, and
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it would be nice not to need to hold the backpointer here.
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def __init__(self, file_id, name, kind='file', text_id=None,
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__slots__ = ['text_sha1', 'text_size', 'file_id', 'name', 'kind',
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'text_id', 'parent_id', 'children', 'executable',
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def _add_text_to_weave(self, new_lines, parents, weave_store, transaction):
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weave_store.add_text(self.file_id, self.revision, new_lines, parents,
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def detect_changes(self, old_entry):
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"""Return a (text_modified, meta_modified) from this to old_entry.
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_read_tree_state must have been called on self and old_entry prior to
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calling detect_changes.
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def diff(self, text_diff, from_label, tree, to_label, to_entry, to_tree,
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output_to, reverse=False):
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"""Perform a diff from this to to_entry.
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text_diff will be used for textual difference calculation.
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This is a template method, override _diff in child classes.
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self._read_tree_state(tree)
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# cannot diff from one kind to another - you must do a removal
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# and an addif they do not match.
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assert self.kind == to_entry.kind
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to_entry._read_tree_state(to_tree)
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self._diff(text_diff, from_label, tree, to_label, to_entry, to_tree,
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def _diff(self, text_diff, from_label, tree, to_label, to_entry, to_tree,
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output_to, reverse=False):
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"""Perform a diff between two entries of the same kind."""
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def find_previous_heads(self, previous_inventories, entry_weave):
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"""Return the revisions and entries that directly preceed this.
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Returned as a map from revision to inventory entry.
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This is a map containing the file revisions in all parents
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for which the file exists, and its revision is not a parent of
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any other. If the file is new, the set will be empty.
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def get_ancestors(weave, entry):
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return set(map(weave.idx_to_name,
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weave.inclusions([weave.lookup(entry.revision)])))
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for inv in previous_inventories:
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if self.file_id in inv:
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ie = inv[self.file_id]
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assert ie.file_id == self.file_id
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if ie.revision in heads:
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# fixup logic, there was a bug in revision updates.
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# with x bit support.
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if heads[ie.revision].executable != ie.executable:
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heads[ie.revision].executable = False
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ie.executable = False
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except AttributeError:
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assert heads[ie.revision] == ie
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# may want to add it.
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# may already be covered:
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already_present = 0 != len(
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[head for head in heads
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if ie.revision in head_ancestors[head]])
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# an ancestor of a known head.
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ancestors = get_ancestors(entry_weave, ie)
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# may knock something else out:
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check_heads = list(heads.keys())
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for head in check_heads:
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if head in ancestors:
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# this head is not really a head
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head_ancestors[ie.revision] = ancestors
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heads[ie.revision] = ie
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def get_tar_item(self, root, dp, now, tree):
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"""Get a tarfile item and a file stream for its content."""
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item = tarfile.TarInfo(os.path.join(root, dp))
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# TODO: would be cool to actually set it to the timestamp of the
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# revision it was last changed
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fileobj = self._put_in_tar(item, tree)
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"""Return true if the object this entry represents has textual data.
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Note that textual data includes binary content.
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Also note that all entries get weave files created for them.
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This attribute is primarily used when upgrading from old trees that
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did not have the weave index for all inventory entries.
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def __init__(self, file_id, name, parent_id, text_id=None):
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"""Create an InventoryEntry
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The filename must be a single component, relative to the
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parent directory; it cannot be a whole path or relative name.
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>>> e = InventoryEntry('123', 'hello.c')
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>>> e = InventoryFile('123', 'hello.c', ROOT_ID)
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>>> e = InventoryEntry('123', 'src/hello.c')
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>>> e = InventoryFile('123', 'src/hello.c', ROOT_ID)
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Traceback (most recent call last):
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BzrError: ("InventoryEntry name is not a simple filename: 'src/hello.c'", [])
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BzrCheckError: InventoryEntry name 'src/hello.c' is invalid
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if len(splitpath(name)) != 1:
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bailout('InventoryEntry name is not a simple filename: %r'
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assert isinstance(name, basestring), name
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if '/' in name or '\\' in name:
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raise BzrCheckError('InventoryEntry name %r is invalid' % name)
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self.executable = False
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self.text_sha1 = None
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self.text_size = None
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self.file_id = file_id
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assert kind in ['file', 'directory']
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self.text_id = text_id
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self.parent_id = parent_id
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self.text_sha1 = None
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self.text_size = None
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self.symlink_target = None
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def kind_character(self):
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"""Return a short kind indicator useful for appending to names."""
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raise BzrError('unknown kind %r' % self.kind)
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known_kinds = ('file', 'directory', 'symlink', 'root_directory')
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def _put_in_tar(self, item, tree):
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"""populate item for stashing in a tar, and return the content stream.
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If no content is available, return None.
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raise BzrError("don't know how to export {%s} of kind %r" %
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(self.file_id, self.kind))
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def put_on_disk(self, dest, dp, tree):
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"""Create a representation of self on disk in the prefix dest.
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This is a template method - implement _put_on_disk in subclasses.
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fullpath = appendpath(dest, dp)
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self._put_on_disk(fullpath, tree)
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mutter(" export {%s} kind %s to %s" % (self.file_id, self.kind, fullpath))
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def _put_on_disk(self, fullpath, tree):
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"""Put this entry onto disk at fullpath, from tree tree."""
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raise BzrError("don't know how to export {%s} of kind %r" % (self.file_id, self.kind))
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def sorted_children(self):
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l = self.children.items()
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def versionable_kind(kind):
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return kind in ('file', 'directory', 'symlink')
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def check(self, checker, rev_id, inv, tree):
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"""Check this inventory entry is intact.
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This is a template method, override _check for kind specific
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if self.parent_id != None:
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if not inv.has_id(self.parent_id):
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raise BzrCheckError('missing parent {%s} in inventory for revision {%s}'
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% (self.parent_id, rev_id))
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self._check(checker, rev_id, tree)
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def _check(self, checker, rev_id, tree):
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"""Check this inventory entry for kind specific errors."""
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raise BzrCheckError('unknown entry kind %r in revision {%s}' %
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other = InventoryEntry(self.file_id, self.name, self.kind,
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self.text_id, self.parent_id)
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other.text_sha1 = self.text_sha1
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other.text_size = self.text_size
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"""Clone this inventory entry."""
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raise NotImplementedError
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def _get_snapshot_change(self, previous_entries):
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if len(previous_entries) > 1:
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elif len(previous_entries) == 0:
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return 'modified/renamed/reparented'
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def __repr__(self):
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return ("%s(%r, %r, kind=%r, parent_id=%r)"
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return ("%s(%r, %r, parent_id=%r)"
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% (self.__class__.__name__,
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def to_element(self):
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"""Convert to XML element"""
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e.set('name', self.name)
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e.set('file_id', self.file_id)
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e.set('kind', self.kind)
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if self.text_size is not None:
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e.set('text_size', '%d' % self.text_size)
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for f in ['text_id', 'text_sha1', 'parent_id']:
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def from_element(cls, elt):
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assert elt.tag == 'entry'
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self = cls(elt.get('file_id'), elt.get('name'), elt.get('kind'))
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self.text_id = elt.get('text_id')
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self.text_sha1 = elt.get('text_sha1')
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self.parent_id = elt.get('parent_id')
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## mutter("read inventoryentry: %r" % (elt.attrib))
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v = elt.get('text_size')
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self.text_size = v and int(v)
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from_element = classmethod(from_element)
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def __cmp__(self, other):
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def snapshot(self, revision, path, previous_entries,
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work_tree, weave_store, transaction):
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"""Make a snapshot of this entry which may or may not have changed.
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This means that all its fields are populated, that it has its
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text stored in the text store or weave.
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mutter('new parents of %s are %r', path, previous_entries)
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self._read_tree_state(work_tree)
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if len(previous_entries) == 1:
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# cannot be unchanged unless there is only one parent file rev.
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parent_ie = previous_entries.values()[0]
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if self._unchanged(parent_ie):
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mutter("found unchanged entry")
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self.revision = parent_ie.revision
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return self.snapshot_revision(revision, previous_entries,
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work_tree, weave_store, transaction)
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def snapshot_revision(self, revision, previous_entries, work_tree,
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weave_store, transaction):
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"""Record this revision unconditionally."""
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mutter('new revision for {%s}', self.file_id)
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self.revision = revision
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change = self._get_snapshot_change(previous_entries)
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self._snapshot_text(previous_entries, work_tree, weave_store,
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def _snapshot_text(self, file_parents, work_tree, weave_store, transaction):
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"""Record the 'text' of this entry, whatever form that takes.
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This default implementation simply adds an empty text.
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mutter('storing file {%s} in revision {%s}',
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self.file_id, self.revision)
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self._add_text_to_weave([], file_parents, weave_store, transaction)
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def __eq__(self, other):
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if not isinstance(other, InventoryEntry):
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return NotImplemented
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return cmp(self.file_id, other.file_id) \
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or cmp(self.name, other.name) \
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or cmp(self.text_sha1, other.text_sha1) \
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or cmp(self.text_size, other.text_size) \
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or cmp(self.text_id, other.text_id) \
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or cmp(self.parent_id, other.parent_id) \
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or cmp(self.kind, other.kind)
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class Inventory(XMLMixin):
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return ((self.file_id == other.file_id)
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and (self.name == other.name)
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and (other.symlink_target == self.symlink_target)
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and (self.text_sha1 == other.text_sha1)
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and (self.text_size == other.text_size)
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and (self.text_id == other.text_id)
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and (self.parent_id == other.parent_id)
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and (self.kind == other.kind)
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and (self.revision == other.revision)
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and (self.executable == other.executable)
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def __ne__(self, other):
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return not (self == other)
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raise ValueError('not hashable')
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def _unchanged(self, previous_ie):
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"""Has this entry changed relative to previous_ie.
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This method should be overriden in child classes.
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# different inv parent
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if previous_ie.parent_id != self.parent_id:
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elif previous_ie.name != self.name:
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def _read_tree_state(self, work_tree):
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"""Populate fields in the inventory entry from the given tree.
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Note that this should be modified to be a noop on virtual trees
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as all entries created there are prepopulated.
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# TODO: Rather than running this manually, we should check the
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# working sha1 and other expensive properties when they're
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# first requested, or preload them if they're already known
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pass # nothing to do by default
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class RootEntry(InventoryEntry):
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def _check(self, checker, rev_id, tree):
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"""See InventoryEntry._check"""
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def __init__(self, file_id):
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self.file_id = file_id
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self.kind = 'root_directory'
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self.parent_id = None
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def __eq__(self, other):
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if not isinstance(other, RootEntry):
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return NotImplemented
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return (self.file_id == other.file_id) \
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and (self.children == other.children)
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class InventoryDirectory(InventoryEntry):
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"""A directory in an inventory."""
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def _check(self, checker, rev_id, tree):
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"""See InventoryEntry._check"""
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if self.text_sha1 != None or self.text_size != None or self.text_id != None:
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raise BzrCheckError('directory {%s} has text in revision {%s}'
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% (self.file_id, rev_id))
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other = InventoryDirectory(self.file_id, self.name, self.parent_id)
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other.revision = self.revision
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# note that children are *not* copied; they're pulled across when
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def __init__(self, file_id, name, parent_id):
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super(InventoryDirectory, self).__init__(file_id, name, parent_id)
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self.kind = 'directory'
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def kind_character(self):
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"""See InventoryEntry.kind_character."""
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def _put_in_tar(self, item, tree):
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"""See InventoryEntry._put_in_tar."""
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item.type = tarfile.DIRTYPE
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def _put_on_disk(self, fullpath, tree):
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"""See InventoryEntry._put_on_disk."""
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class InventoryFile(InventoryEntry):
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"""A file in an inventory."""
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def _check(self, checker, rev_id, tree):
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"""See InventoryEntry._check"""
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revision = self.revision
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t = (self.file_id, revision)
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if t in checker.checked_texts:
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prev_sha = checker.checked_texts[t]
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if prev_sha != self.text_sha1:
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raise BzrCheckError('mismatched sha1 on {%s} in {%s}' %
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(self.file_id, rev_id))
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checker.repeated_text_cnt += 1
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mutter('check version {%s} of {%s}', rev_id, self.file_id)
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file_lines = tree.get_file_lines(self.file_id)
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checker.checked_text_cnt += 1
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if self.text_size != sum(map(len, file_lines)):
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raise BzrCheckError('text {%s} wrong size' % self.text_id)
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if self.text_sha1 != sha_strings(file_lines):
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raise BzrCheckError('text {%s} wrong sha1' % self.text_id)
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checker.checked_texts[t] = self.text_sha1
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other = InventoryFile(self.file_id, self.name, self.parent_id)
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other.executable = self.executable
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other.text_id = self.text_id
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other.text_sha1 = self.text_sha1
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other.text_size = self.text_size
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other.revision = self.revision
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def detect_changes(self, old_entry):
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"""See InventoryEntry.detect_changes."""
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assert self.text_sha1 != None
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assert old_entry.text_sha1 != None
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text_modified = (self.text_sha1 != old_entry.text_sha1)
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meta_modified = (self.executable != old_entry.executable)
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return text_modified, meta_modified
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def _diff(self, text_diff, from_label, tree, to_label, to_entry, to_tree,
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output_to, reverse=False):
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"""See InventoryEntry._diff."""
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from_text = tree.get_file(self.file_id).readlines()
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to_text = to_tree.get_file(to_entry.file_id).readlines()
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text_diff(from_label, from_text,
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to_label, to_text, output_to)
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text_diff(to_label, to_text,
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from_label, from_text, output_to)
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"""See InventoryEntry.has_text."""
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def __init__(self, file_id, name, parent_id):
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super(InventoryFile, self).__init__(file_id, name, parent_id)
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def kind_character(self):
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"""See InventoryEntry.kind_character."""
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def _put_in_tar(self, item, tree):
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"""See InventoryEntry._put_in_tar."""
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item.type = tarfile.REGTYPE
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fileobj = tree.get_file(self.file_id)
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item.size = self.text_size
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if tree.is_executable(self.file_id):
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def _put_on_disk(self, fullpath, tree):
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"""See InventoryEntry._put_on_disk."""
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pumpfile(tree.get_file(self.file_id), file(fullpath, 'wb'))
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if tree.is_executable(self.file_id):
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os.chmod(fullpath, 0755)
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def _read_tree_state(self, work_tree):
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"""See InventoryEntry._read_tree_state."""
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self.text_sha1 = work_tree.get_file_sha1(self.file_id)
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self.executable = work_tree.is_executable(self.file_id)
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def _snapshot_text(self, file_parents, work_tree, weave_store, transaction):
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"""See InventoryEntry._snapshot_text."""
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mutter('storing file {%s} in revision {%s}',
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self.file_id, self.revision)
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# special case to avoid diffing on renames or
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if (len(file_parents) == 1
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and self.text_sha1 == file_parents.values()[0].text_sha1
563
and self.text_size == file_parents.values()[0].text_size):
564
previous_ie = file_parents.values()[0]
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weave_store.add_identical_text(
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self.file_id, previous_ie.revision,
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self.revision, file_parents, transaction)
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new_lines = work_tree.get_file(self.file_id).readlines()
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self._add_text_to_weave(new_lines, file_parents, weave_store,
572
self.text_sha1 = sha_strings(new_lines)
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self.text_size = sum(map(len, new_lines))
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def _unchanged(self, previous_ie):
577
"""See InventoryEntry._unchanged."""
578
compatible = super(InventoryFile, self)._unchanged(previous_ie)
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if self.text_sha1 != previous_ie.text_sha1:
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# FIXME: 20050930 probe for the text size when getting sha1
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# in _read_tree_state
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self.text_size = previous_ie.text_size
585
if self.executable != previous_ie.executable:
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class InventoryLink(InventoryEntry):
591
"""A file in an inventory."""
593
__slots__ = ['symlink_target']
595
def _check(self, checker, rev_id, tree):
596
"""See InventoryEntry._check"""
597
if self.text_sha1 != None or self.text_size != None or self.text_id != None:
598
raise BzrCheckError('symlink {%s} has text in revision {%s}'
599
% (self.file_id, rev_id))
600
if self.symlink_target == None:
601
raise BzrCheckError('symlink {%s} has no target in revision {%s}'
602
% (self.file_id, rev_id))
605
other = InventoryLink(self.file_id, self.name, self.parent_id)
606
other.symlink_target = self.symlink_target
607
other.revision = self.revision
610
def detect_changes(self, old_entry):
611
"""See InventoryEntry.detect_changes."""
612
# FIXME: which _modified field should we use ? RBC 20051003
613
text_modified = (self.symlink_target != old_entry.symlink_target)
615
mutter(" symlink target changed")
616
meta_modified = False
617
return text_modified, meta_modified
619
def _diff(self, text_diff, from_label, tree, to_label, to_entry, to_tree,
620
output_to, reverse=False):
621
"""See InventoryEntry._diff."""
622
from_text = self.symlink_target
623
if to_entry is not None:
624
to_text = to_entry.symlink_target
629
print >>output_to, '=== target changed %r => %r' % (from_text, to_text)
632
print >>output_to, '=== target was %r' % self.symlink_target
634
print >>output_to, '=== target is %r' % self.symlink_target
636
def __init__(self, file_id, name, parent_id):
637
super(InventoryLink, self).__init__(file_id, name, parent_id)
638
self.kind = 'symlink'
640
def kind_character(self):
641
"""See InventoryEntry.kind_character."""
644
def _put_in_tar(self, item, tree):
645
"""See InventoryEntry._put_in_tar."""
646
iterm.type = tarfile.SYMTYPE
650
item.linkname = self.symlink_target
653
def _put_on_disk(self, fullpath, tree):
654
"""See InventoryEntry._put_on_disk."""
656
os.symlink(self.symlink_target, fullpath)
658
raise BzrError("Failed to create symlink %r -> %r, error: %s" % (fullpath, self.symlink_target, e))
660
def _read_tree_state(self, work_tree):
661
"""See InventoryEntry._read_tree_state."""
662
self.symlink_target = work_tree.get_symlink_target(self.file_id)
664
def _unchanged(self, previous_ie):
665
"""See InventoryEntry._unchanged."""
666
compatible = super(InventoryLink, self)._unchanged(previous_ie)
667
if self.symlink_target != previous_ie.symlink_target:
672
class Inventory(object):
199
673
"""Inventory of versioned files in a tree.
201
An Inventory acts like a set of InventoryEntry items. You can
202
also look files up by their file_id or name.
204
May be read from and written to a metadata file in a tree. To
205
manipulate the inventory (for example to add a file), it is read
206
in, modified, and then written back out.
675
This describes which file_id is present at each point in the tree,
676
and possibly the SHA-1 or other information about the file.
677
Entries can be looked up either by path or by file_id.
208
679
The inventory represents a typical unix file tree, with
209
680
directories containing files and subdirectories. We never store