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Differential D3502

shortest: move revnum-disambiguation out of revlog
ClosedPublic

Authored by martinvonz on May 8 2018, 2:07 PM.

Details

Reviewers
indygreg
Group Reviewers
hg-reviewers
Commits
rHG3ac950cd5978: shortest: move revnum-disambiguation out of revlog
Summary

I want to be able to change how we disambiguate and I think having
revlog.shortest() worry only about finding a prefix that's unambiguous
among nodeids makes more sense.

This slows down hg log -T '{shortest(node,1)}\n' from 4.0s to 4.1s.

Diff Detail

Repository
rHG Mercurial
Lint
Automatic diff as part of commit; lint not applicable.
Unit
Automatic diff as part of commit; unit tests not applicable.

Event Timeline

martinvonz created this revision.May 8 2018, 2:07 PM
martinvonz updated this revision to Diff 8625.May 10 2018, 12:02 PM
yuja added a subscriber: yuja.May 11 2018, 10:20 AM

+ def disambiguate(prefix):
+ """Disambiguate against revnums."""
+ hexnode = hex(node)
+ for length in range(len(prefix), 41):

Nit: range(len(prefix), len(hexnode) + 1) seems slightly better than
using a magic number outside the revlog module.

+ prefix = hexnode[:length]
+ if not isrev(prefix):
+ return prefix

Closed by commit rHG3ac950cd5978: shortest: move revnum-disambiguation out of revlog (authored by martinvonz). · Explain WhyMay 11 2018, 3:32 PM
This revision was automatically updated to reflect the committed changes.

Revision Contents
Changeset List

PathPackages
Mmercurial/revlog.py (15 lines)
Mmercurial/scmutil.py (24 lines)

Diff 8642

mercurial/revlog.py

n = self._partialmatch(id) n = self._partialmatch(id)
if n: if n:
return n return n
raise LookupError(id, self.indexfile, _('no match found')) raise LookupError(id, self.indexfile, _('no match found'))
def shortest(self, node, minlength=1): def shortest(self, node, minlength=1):
"""Find the shortest unambiguous prefix that matches node.""" """Find the shortest unambiguous prefix that matches node."""
def isrev(prefix):
try:
i = int(prefix)
# if we are a pure int, then starting with zero will not be
# confused as a rev; or, obviously, if the int is larger
# than the value of the tip rev
if prefix[0] == '0' or i > len(self):
return False
return True
except ValueError:
return False
def isvalid(prefix): def isvalid(prefix):
try: try:
node = self._partialmatch(prefix) node = self._partialmatch(prefix)
except error.RevlogError: except error.RevlogError:
return False return False
except error.WdirUnsupported: except error.WdirUnsupported:
# single 'ff...' match # single 'ff...' match
return True return True
if node is None: if node is None:
raise LookupError(node, self.indexfile, _('no node')) raise LookupError(node, self.indexfile, _('no node'))
return True return True
def maybewdir(prefix): def maybewdir(prefix):
return all(c == 'f' for c in prefix) return all(c == 'f' for c in prefix)
hexnode = hex(node) hexnode = hex(node)
def disambiguate(hexnode, minlength): def disambiguate(hexnode, minlength):
"""Disambiguate against wdirid."""
for length in range(minlength, 41): for length in range(minlength, 41):
prefix = hexnode[:length] prefix = hexnode[:length]
if not isrev(prefix) and not maybewdir(prefix): if not maybewdir(prefix):
return prefix return prefix
if not getattr(self, 'filteredrevs', None): if not getattr(self, 'filteredrevs', None):
try: try:
length = max(self.index.shortest(node), minlength) length = max(self.index.shortest(node), minlength)
return disambiguate(hexnode, length) return disambiguate(hexnode, length)
except RevlogError: except RevlogError:
if node != wdirid: if node != wdirid:

mercurial/scmutil.py

repo.changelog.rev(node) # make sure node isn't filtered repo.changelog.rev(node) # make sure node isn't filtered
return node return node
def shortesthexnodeidprefix(repo, node, minlength=1): def shortesthexnodeidprefix(repo, node, minlength=1):
"""Find the shortest unambiguous prefix that matches hexnode.""" """Find the shortest unambiguous prefix that matches hexnode."""
# _partialmatch() of filtered changelog could take O(len(repo)) time, # _partialmatch() of filtered changelog could take O(len(repo)) time,
# which would be unacceptably slow. so we look for hash collision in # which would be unacceptably slow. so we look for hash collision in
# unfiltered space, which means some hashes may be slightly longer. # unfiltered space, which means some hashes may be slightly longer.
cl = repo.unfiltered().changelog
def isrev(prefix):
try:
i = int(prefix)
# if we are a pure int, then starting with zero will not be
# confused as a rev; or, obviously, if the int is larger
# than the value of the tip rev
if prefix[0] == '0' or i > len(cl):
return False
return True
except ValueError:
return False
def disambiguate(prefix):
"""Disambiguate against revnums."""
hexnode = hex(node)
for length in range(len(prefix), 41):
prefix = hexnode[:length]
if not isrev(prefix):
return prefix
try: try:
return repo.unfiltered().changelog.shortest(node, minlength) return disambiguate(cl.shortest(node, minlength))
except error.LookupError: except error.LookupError:
raise error.RepoLookupError() raise error.RepoLookupError()
def isrevsymbol(repo, symbol): def isrevsymbol(repo, symbol):
"""Checks if a symbol exists in the repo. """Checks if a symbol exists in the repo.
See revsymbol() for details. Raises error.LookupError if the symbol is an See revsymbol() for details. Raises error.LookupError if the symbol is an
ambiguous nodeid prefix. ambiguous nodeid prefix.