diff --git a/mercurial/revlog.py b/mercurial/revlog.py --- a/mercurial/revlog.py +++ b/mercurial/revlog.py @@ -2188,7 +2188,6 @@ nodesorder = 'storage' frev = self.rev - fnode = self.node if nodesorder == 'nodes': revs = [frev(n) for n in nodes] @@ -2199,100 +2198,17 @@ revs = set(frev(n) for n in nodes) revs = dagop.linearize(revs, self.parentrevs) - prevrev = None - - if deltaprevious or assumehaveparentrevisions: - prevrev = self.parentrevs(revs[0])[0] - - # Set of revs available to delta against. - available = set() - - for rev in revs: - if rev == nullrev: - continue - - node = fnode(rev) - deltaparentrev = self.deltaparent(rev) - p1rev, p2rev = self.parentrevs(rev) - - # Forced delta against previous mode. - if deltaprevious: - baserev = prevrev - - # Revlog is configured to use full snapshots. Stick to that. - elif not self._storedeltachains: - baserev = nullrev - - # There is a delta in storage. We try to use that because it - # amounts to effectively copying data from storage and is - # therefore the fastest. - elif deltaparentrev != nullrev: - # Base revision was already emitted in this group. We can - # always safely use the delta. - if deltaparentrev in available: - baserev = deltaparentrev - - # Base revision is a parent that hasn't been emitted already. - # Use it if we can assume the receiver has the parent revision. - elif (assumehaveparentrevisions - and deltaparentrev in (p1rev, p2rev)): - baserev = deltaparentrev - - # No guarantee the receiver has the delta parent. Send delta - # against last revision (if possible), which in the common case - # should be similar enough to this revision that the delta is - # reasonable. - elif prevrev is not None: - baserev = prevrev - else: - baserev = nullrev - - # Storage has a fulltext revision. - - # Let's use the previous revision, which is as good a guess as any. - # There is definitely room to improve this logic. - elif prevrev is not None: - baserev = prevrev - else: - baserev = nullrev - - # But we can't actually use our chosen delta base for whatever - # reason. Reset to fulltext. - if baserev != nullrev and not self.candelta(baserev, rev): - baserev = nullrev - - revision = None - delta = None - baserevisionsize = None - - if revisiondata: - if self.iscensored(baserev) or self.iscensored(rev): - try: - revision = self.revision(node, raw=True) - except error.CensoredNodeError as e: - revision = e.tombstone - - if baserev != nullrev: - baserevisionsize = self.rawsize(baserev) - - elif baserev == nullrev and not deltaprevious: - revision = self.revision(node, raw=True) - available.add(rev) - else: - delta = self.revdiff(baserev, rev) - available.add(rev) - - yield revlogrevisiondelta( - node=node, - p1node=fnode(p1rev), - p2node=fnode(p2rev), - basenode=fnode(baserev), - flags=self.flags(rev), - baserevisionsize=baserevisionsize, - revision=revision, - delta=delta) - - prevrev = rev + return storageutil.emitrevisions( + self, revs, revlogrevisiondelta, + deltaparentfn=self.deltaparent, + candeltafn=self.candelta, + rawsizefn=self.rawsize, + revdifffn=self.revdiff, + flagsfn=self.flags, + sendfulltext=not self._storedeltachains, + revisiondata=revisiondata, + assumehaveparentrevisions=assumehaveparentrevisions, + deltaprevious=deltaprevious) DELTAREUSEALWAYS = 'always' DELTAREUSESAMEREVS = 'samerevs' diff --git a/mercurial/utils/storageutil.py b/mercurial/utils/storageutil.py --- a/mercurial/utils/storageutil.py +++ b/mercurial/utils/storageutil.py @@ -262,3 +262,149 @@ futurelargelinkrevs.add(plinkrev) return strippoint, brokenrevs + +def emitrevisions(store, revs, resultcls, deltaparentfn, candeltafn, + rawsizefn, revdifffn, flagsfn, sendfulltext=False, + revisiondata=False, assumehaveparentrevisions=False, + deltaprevious=False): + """Generic implementation of ifiledata.emitrevisions(). + + Emitting revision data is subtly complex. This function attempts to + encapsulate all the logic for doing so in a backend-agnostic way. + + ``store`` + Object conforming to ``ifilestorage`` interface. + + ``revs`` + List of integer revision numbers whose data to emit. + + ``resultcls`` + A type implementing the ``irevisiondelta`` interface that will be + constructed and returned. + + ``deltaparentfn`` + Callable receiving a revision number and returning the revision number + of a revision that the internal delta is stored against. This delta + will be preferred over computing a new arbitrary delta. + + ``candeltafn`` + Callable receiving a pair of revision numbers that returns a bool + indicating whether a delta between them can be produced. + + ``rawsizefn`` + Callable receiving a revision number and returning the length of the + ``store.revision(rev, raw=True)``. + + ``revdifffn`` + Callable receiving a pair of revision numbers that returns a delta + between them. + + ``flagsfn`` + Callable receiving a revision number and returns the integer flags + value for it. + + ``sendfulltext`` + Whether to send fulltext revisions instead of deltas, if allowed. + + ``revisiondata`` + ``assumehaveparentrevisions`` + ``deltaprevious`` + See ``ifiledata.emitrevisions()`` interface documentation. + """ + + fnode = store.node + + prevrev = None + + if deltaprevious or assumehaveparentrevisions: + prevrev = store.parentrevs(revs[0])[0] + + # Set of revs available to delta against. + available = set() + + for rev in revs: + if rev == nullrev: + continue + + node = fnode(rev) + deltaparentrev = deltaparentfn(rev) + p1rev, p2rev = store.parentrevs(rev) + + # Forced delta against previous mode. + if deltaprevious: + baserev = prevrev + + # We're instructed to send fulltext. Honor that. + elif sendfulltext: + baserev = nullrev + + # There is a delta in storage. We try to use that because it + # amounts to effectively copying data from storage and is + # therefore the fastest. + elif deltaparentrev != nullrev: + # Base revision was already emitted in this group. We can + # always safely use the delta. + if deltaparentrev in available: + baserev = deltaparentrev + + # Base revision is a parent that hasn't been emitted already. + # Use it if we can assume the receiver has the parent revision. + elif (assumehaveparentrevisions + and deltaparentrev in (p1rev, p2rev)): + baserev = deltaparentrev + + # No guarantee the receiver has the delta parent. Send delta + # against last revision (if possible), which in the common case + # should be similar enough to this revision that the delta is + # reasonable. + elif prevrev is not None: + baserev = prevrev + else: + baserev = nullrev + + # Storage has a fulltext revision. + + # Let's use the previous revision, which is as good a guess as any. + # There is definitely room to improve this logic. + elif prevrev is not None: + baserev = prevrev + else: + baserev = nullrev + + # But we can't actually use our chosen delta base for whatever + # reason. Reset to fulltext. + if baserev != nullrev and not candeltafn(baserev, rev): + baserev = nullrev + + revision = None + delta = None + baserevisionsize = None + + if revisiondata: + if store.iscensored(baserev) or store.iscensored(rev): + try: + revision = store.revision(node, raw=True) + except error.CensoredNodeError as e: + revision = e.tombstone + + if baserev != nullrev: + baserevisionsize = rawsizefn(baserev) + + elif baserev == nullrev and not deltaprevious: + revision = store.revision(node, raw=True) + available.add(rev) + else: + delta = revdifffn(baserev, rev) + available.add(rev) + + yield resultcls( + node=node, + p1node=fnode(p1rev), + p2node=fnode(p2rev), + basenode=fnode(baserev), + flags=flagsfn(rev), + baserevisionsize=baserevisionsize, + revision=revision, + delta=delta) + + prevrev = rev