Mercurial > hg
view mercurial/filelog.py @ 45059:79f6f9fa18c1
documentation: add some internals documentation about bid merge
This is an important algorithm that was only documented on the wiki so far.
Some update to the algorithm (and associated doc) is to expected in the future
since the bid merge algorithm is bug-ridden when it comes to file deletion comes
to play.
Differential Revision: https://phab.mercurial-scm.org/D8711
author | Pierre-Yves David <pierre-yves.david@octobus.net> |
---|---|
date | Mon, 22 Jun 2020 13:32:20 +0200 |
parents | 687b865b95ad |
children | a5206e71c536 |
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# filelog.py - file history class for mercurial # # Copyright 2005-2007 Matt Mackall <mpm@selenic.com> # # This software may be used and distributed according to the terms of the # GNU General Public License version 2 or any later version. from __future__ import absolute_import from .i18n import _ from .node import ( nullid, nullrev, ) from . import ( error, revlog, ) from .interfaces import ( repository, util as interfaceutil, ) from .utils import storageutil @interfaceutil.implementer(repository.ifilestorage) class filelog(object): def __init__(self, opener, path): self._revlog = revlog.revlog( opener, b'/'.join((b'data', path + b'.i')), censorable=True ) # Full name of the user visible file, relative to the repository root. # Used by LFS. self._revlog.filename = path def __len__(self): return len(self._revlog) def __iter__(self): return self._revlog.__iter__() def hasnode(self, node): if node in (nullid, nullrev): return False try: self._revlog.rev(node) return True except (TypeError, ValueError, IndexError, error.LookupError): return False def revs(self, start=0, stop=None): return self._revlog.revs(start=start, stop=stop) def parents(self, node): return self._revlog.parents(node) def parentrevs(self, rev): return self._revlog.parentrevs(rev) def rev(self, node): return self._revlog.rev(node) def node(self, rev): return self._revlog.node(rev) def lookup(self, node): return storageutil.fileidlookup( self._revlog, node, self._revlog.indexfile ) def linkrev(self, rev): return self._revlog.linkrev(rev) def commonancestorsheads(self, node1, node2): return self._revlog.commonancestorsheads(node1, node2) # Used by dagop.blockdescendants(). def descendants(self, revs): return self._revlog.descendants(revs) def heads(self, start=None, stop=None): return self._revlog.heads(start, stop) # Used by hgweb, children extension. def children(self, node): return self._revlog.children(node) def iscensored(self, rev): return self._revlog.iscensored(rev) def revision(self, node, _df=None, raw=False): return self._revlog.revision(node, _df=_df, raw=raw) def rawdata(self, node, _df=None): return self._revlog.rawdata(node, _df=_df) def emitrevisions( self, nodes, nodesorder=None, revisiondata=False, assumehaveparentrevisions=False, deltamode=repository.CG_DELTAMODE_STD, ): return self._revlog.emitrevisions( nodes, nodesorder=nodesorder, revisiondata=revisiondata, assumehaveparentrevisions=assumehaveparentrevisions, deltamode=deltamode, ) def addrevision( self, revisiondata, transaction, linkrev, p1, p2, node=None, flags=revlog.REVIDX_DEFAULT_FLAGS, cachedelta=None, ): return self._revlog.addrevision( revisiondata, transaction, linkrev, p1, p2, node=node, flags=flags, cachedelta=cachedelta, ) def addgroup( self, deltas, linkmapper, transaction, addrevisioncb=None, maybemissingparents=False, ): if maybemissingparents: raise error.Abort( _( b'revlog storage does not support missing ' b'parents write mode' ) ) return self._revlog.addgroup( deltas, linkmapper, transaction, addrevisioncb=addrevisioncb ) def getstrippoint(self, minlink): return self._revlog.getstrippoint(minlink) def strip(self, minlink, transaction): return self._revlog.strip(minlink, transaction) def censorrevision(self, tr, node, tombstone=b''): return self._revlog.censorrevision(tr, node, tombstone=tombstone) def files(self): return self._revlog.files() def read(self, node): return storageutil.filtermetadata(self.revision(node)) def add(self, text, meta, transaction, link, p1=None, p2=None): if meta or text.startswith(b'\1\n'): text = storageutil.packmeta(meta, text) return self.addrevision(text, transaction, link, p1, p2) def renamed(self, node): return storageutil.filerevisioncopied(self, node) def size(self, rev): """return the size of a given revision""" # for revisions with renames, we have to go the slow way node = self.node(rev) if self.renamed(node): return len(self.read(node)) if self.iscensored(rev): return 0 # XXX if self.read(node).startswith("\1\n"), this returns (size+4) return self._revlog.size(rev) def cmp(self, node, text): """compare text with a given file revision returns True if text is different than what is stored. """ return not storageutil.filedataequivalent(self, node, text) def verifyintegrity(self, state): return self._revlog.verifyintegrity(state) def storageinfo( self, exclusivefiles=False, sharedfiles=False, revisionscount=False, trackedsize=False, storedsize=False, ): return self._revlog.storageinfo( exclusivefiles=exclusivefiles, sharedfiles=sharedfiles, revisionscount=revisionscount, trackedsize=trackedsize, storedsize=storedsize, ) # TODO these aren't part of the interface and aren't internal methods. # Callers should be fixed to not use them. # Used by bundlefilelog, unionfilelog. @property def indexfile(self): return self._revlog.indexfile @indexfile.setter def indexfile(self, value): self._revlog.indexfile = value # Used by repo upgrade. def clone(self, tr, destrevlog, **kwargs): if not isinstance(destrevlog, filelog): raise error.ProgrammingError(b'expected filelog to clone()') return self._revlog.clone(tr, destrevlog._revlog, **kwargs) class narrowfilelog(filelog): """Filelog variation to be used with narrow stores.""" def __init__(self, opener, path, narrowmatch): super(narrowfilelog, self).__init__(opener, path) self._narrowmatch = narrowmatch def renamed(self, node): res = super(narrowfilelog, self).renamed(node) # Renames that come from outside the narrowspec are problematic # because we may lack the base text for the rename. This can result # in code attempting to walk the ancestry or compute a diff # encountering a missing revision. We address this by silently # removing rename metadata if the source file is outside the # narrow spec. # # A better solution would be to see if the base revision is available, # rather than assuming it isn't. # # An even better solution would be to teach all consumers of rename # metadata that the base revision may not be available. # # TODO consider better ways of doing this. if res and not self._narrowmatch(res[0]): return None return res def size(self, rev): # Because we have a custom renamed() that may lie, we need to call # the base renamed() to report accurate results. node = self.node(rev) if super(narrowfilelog, self).renamed(node): return len(self.read(node)) else: return super(narrowfilelog, self).size(rev) def cmp(self, node, text): different = super(narrowfilelog, self).cmp(node, text) # Because renamed() may lie, we may get false positives for # different content. Check for this by comparing against the original # renamed() implementation. if different: if super(narrowfilelog, self).renamed(node): t2 = self.read(node) return t2 != text return different