Mercurial > hg
view mercurial/manifest.py @ 17013:c8eda7bbdcab
strip: incrementally update the branchheads cache after a strip
This function augments strip to incrementally update the branchheads cache
rather than recompute it from scratch. This speeds up the performance of strip
and rebase on repos with long history. The performance optimization only
happens if the revisions stripped are all on the same branch and the parents of
the stripped revisions are also on that same branch.
This adds a few test cases, particularly one that reproduces the extra heads
that mpm observed.
author | Joshua Redstone <joshua.redstone@fb.com> |
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date | Fri, 18 May 2012 12:45:47 -0700 |
parents | 525fdb738975 |
children | 9724f8f8850b |
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# manifest.py - manifest revision 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 i18n import _ import mdiff, parsers, error, revlog, util import array, struct class manifestdict(dict): def __init__(self, mapping=None, flags=None): if mapping is None: mapping = {} if flags is None: flags = {} dict.__init__(self, mapping) self._flags = flags def flags(self, f): return self._flags.get(f, "") def withflags(self): return set(self._flags.keys()) def set(self, f, flags): self._flags[f] = flags def copy(self): return manifestdict(self, dict.copy(self._flags)) class manifest(revlog.revlog): def __init__(self, opener): self._mancache = None revlog.revlog.__init__(self, opener, "00manifest.i") def parse(self, lines): mfdict = manifestdict() parsers.parse_manifest(mfdict, mfdict._flags, lines) return mfdict def readdelta(self, node): r = self.rev(node) return self.parse(mdiff.patchtext(self.revdiff(self.deltaparent(r), r))) def readfast(self, node): '''use the faster of readdelta or read''' r = self.rev(node) deltaparent = self.deltaparent(r) if deltaparent != revlog.nullrev and deltaparent in self.parentrevs(r): return self.readdelta(node) return self.read(node) def read(self, node): if node == revlog.nullid: return manifestdict() # don't upset local cache if self._mancache and self._mancache[0] == node: return self._mancache[1] text = self.revision(node) arraytext = array.array('c', text) mapping = self.parse(text) self._mancache = (node, mapping, arraytext) return mapping def _search(self, m, s, lo=0, hi=None): '''return a tuple (start, end) that says where to find s within m. If the string is found m[start:end] are the line containing that string. If start == end the string was not found and they indicate the proper sorted insertion point. This was taken from bisect_left, and modified to find line start/end as it goes along. m should be a buffer or a string s is a string''' def advance(i, c): while i < lenm and m[i] != c: i += 1 return i if not s: return (lo, lo) lenm = len(m) if not hi: hi = lenm while lo < hi: mid = (lo + hi) // 2 start = mid while start > 0 and m[start - 1] != '\n': start -= 1 end = advance(start, '\0') if m[start:end] < s: # we know that after the null there are 40 bytes of sha1 # this translates to the bisect lo = mid + 1 lo = advance(end + 40, '\n') + 1 else: # this translates to the bisect hi = mid hi = start end = advance(lo, '\0') found = m[lo:end] if s == found: # we know that after the null there are 40 bytes of sha1 end = advance(end + 40, '\n') return (lo, end + 1) else: return (lo, lo) def find(self, node, f): '''look up entry for a single file efficiently. return (node, flags) pair if found, (None, None) if not.''' if self._mancache and self._mancache[0] == node: return self._mancache[1].get(f), self._mancache[1].flags(f) text = self.revision(node) start, end = self._search(text, f) if start == end: return None, None l = text[start:end] f, n = l.split('\0') return revlog.bin(n[:40]), n[40:-1] def add(self, map, transaction, link, p1=None, p2=None, changed=None): # apply the changes collected during the bisect loop to our addlist # return a delta suitable for addrevision def addlistdelta(addlist, x): # start from the bottom up # so changes to the offsets don't mess things up. for start, end, content in reversed(x): if content: addlist[start:end] = array.array('c', content) else: del addlist[start:end] return "".join(struct.pack(">lll", start, end, len(content)) + content for start, end, content in x) def checkforbidden(l): for f in l: if '\n' in f or '\r' in f: raise error.RevlogError( _("'\\n' and '\\r' disallowed in filenames: %r") % f) # if we're using the cache, make sure it is valid and # parented by the same node we're diffing against if not (changed and self._mancache and p1 and self._mancache[0] == p1): files = sorted(map) checkforbidden(files) # if this is changed to support newlines in filenames, # be sure to check the templates/ dir again (especially *-raw.tmpl) hex, flags = revlog.hex, map.flags text = ''.join("%s\0%s%s\n" % (f, hex(map[f]), flags(f)) for f in files) arraytext = array.array('c', text) cachedelta = None else: added, removed = changed addlist = self._mancache[2] checkforbidden(added) # combine the changed lists into one list for sorting work = [(x, False) for x in added] work.extend((x, True) for x in removed) # this could use heapq.merge() (from python2.6+) or equivalent # since the lists are already sorted work.sort() delta = [] dstart = None dend = None dline = [""] start = 0 # zero copy representation of addlist as a buffer addbuf = util.buffer(addlist) # start with a readonly loop that finds the offset of # each line and creates the deltas for f, todelete in work: # bs will either be the index of the item or the insert point start, end = self._search(addbuf, f, start) if not todelete: l = "%s\0%s%s\n" % (f, revlog.hex(map[f]), map.flags(f)) else: if start == end: # item we want to delete was not found, error out raise AssertionError( _("failed to remove %s from manifest") % f) l = "" if dstart is not None and dstart <= start and dend >= start: if dend < end: dend = end if l: dline.append(l) else: if dstart is not None: delta.append([dstart, dend, "".join(dline)]) dstart = start dend = end dline = [l] if dstart is not None: delta.append([dstart, dend, "".join(dline)]) # apply the delta to the addlist, and get a delta for addrevision cachedelta = (self.rev(p1), addlistdelta(addlist, delta)) arraytext = addlist text = util.buffer(arraytext) n = self.addrevision(text, transaction, link, p1, p2, cachedelta) self._mancache = (n, map, arraytext) return n