revlog: use node tree (native code) for shortest() calculation
I want to rewrite revlog.shortest() to disambiguate only among hex
nodeids and then disambiguate the result with revnums at a higher
level (in scmutil). However, that would slow down `hg log -T
'{shortest(node,1)}\n'` from 5.0s to 6.8s, which I wasn't sure would
be acceptable. So this patch makes revlog.shortest() use the node tree
for finding the length of the shortest prefix that's unambiguous among
nodeids. Once that has been found, it makes it longer until it is also
not ambiguous with a revnum.
This speeds up `hg log -T '{shortest(node,1)}\n'` from 5.0s to 4.0s.
Differential Revision: https://phab.mercurial-scm.org/D3499
$ cat >> $HGRCPATH <<EOF
> [extensions]
> convert=
> EOF
Prepare orig repo
$ hg init orig
$ cd orig
$ echo foo > foo
$ HGUSER='user name' hg ci -qAm 'foo'
$ cd ..
Explicit --authors
$ cat > authormap.txt <<EOF
> user name = Long User Name
>
> # comment
> this line is ignored
> EOF
$ hg convert --authors authormap.txt orig new
initializing destination new repository
ignoring bad line in author map file authormap.txt: this line is ignored
scanning source...
sorting...
converting...
0 foo
writing author map file $TESTTMP/new/.hg/authormap
$ cat new/.hg/authormap
user name=Long User Name
$ hg -Rnew log
changeset: 0:d89716e88087
tag: tip
user: Long User Name
date: Thu Jan 01 00:00:00 1970 +0000
summary: foo
$ rm -rf new
Implicit .hg/authormap
$ hg init new
$ mv authormap.txt new/.hg/authormap
$ hg convert orig new
ignoring bad line in author map file $TESTTMP/new/.hg/authormap: this line is ignored
scanning source...
sorting...
converting...
0 foo
$ hg -Rnew log
changeset: 0:d89716e88087
tag: tip
user: Long User Name
date: Thu Jan 01 00:00:00 1970 +0000
summary: foo