changectx: increase perf of walk function
When running 'hg cat -r . <file>' it was doing an expensive ctx.walk(m) which
applied the regex to every file in the manifest.
This changes changectx.walk to iterate over just the files in the regex, if no
other patterns are specified. This cuts hg cat time by 50% in our repo and
probably benefits a few other commands as well.
$ "$TESTDIR/hghave" svn svn-bindings || exit 80
$ cat >> $HGRCPATH <<EOF
> [extensions]
> convert =
> EOF
$ convert()
> {
> startrev=$1
> repopath=A-r$startrev-hg
> hg convert --config convert.svn.startrev=$startrev \
> --config convert.svn.trunk=branches/branch1 \
> --config convert.svn.branches=" " \
> --config convert.svn.tags= \
> --datesort svn-repo $repopath
> hg -R $repopath log -G \
> --template '{rev} {desc|firstline} files: {files}\n'
> echo
> }
$ svnadmin create svn-repo
$ svnadmin load -q svn-repo < "$TESTDIR/svn/startrev.svndump"
Convert before branching point
$ convert 3
initializing destination A-r3-hg repository
scanning source...
sorting...
converting...
3 removeb
2 changeaa
1 branch, changeaaa
0 addc,changeaaaa
o 3 addc,changeaaaa files: a c
|
o 2 branch, changeaaa files: a
|
o 1 changeaa files: a
|
o 0 removeb files: a
Convert before branching point
$ convert 4
initializing destination A-r4-hg repository
scanning source...
sorting...
converting...
2 changeaa
1 branch, changeaaa
0 addc,changeaaaa
o 2 addc,changeaaaa files: a c
|
o 1 branch, changeaaa files: a
|
o 0 changeaa files: a
Convert at branching point
$ convert 5
initializing destination A-r5-hg repository
scanning source...
sorting...
converting...
1 branch, changeaaa
0 addc,changeaaaa
o 1 addc,changeaaaa files: a c
|
o 0 branch, changeaaa files: a
Convert last revision only
$ convert 6
initializing destination A-r6-hg repository
scanning source...
sorting...
converting...
0 addc,changeaaaa
o 0 addc,changeaaaa files: a c