manifestmerge: use dicthelpers.diff and join
This patch improves manifestmerge performance significantly.
In a repository with 170,000 files, the following results were observed on a
clean working directory. Revision '.' adds one file.
hg perfmergecalculate -r .
- before: 0.41 seconds
- after: 0.13 seconds
hg perfmergecalculate -r .^
- before: 0.53 seconds
- after: 0.24 seconds
Comparing against '.' is much faster than comparing against '.^' because with
'.', the wctx and p2 manifest strings have the same identity, so comparisons
are simply pointer equality. With '.^', the strings have different identities
so we need to perform memcmps.
Any operation that uses manifestmerge benefits.
- hg update . goes from 2.04 seconds to 1.75
- hg update .^ goes from 2.52 seconds to 2.25
- hg rebase -r . -d .~6 (involves 4 merges) goes from 11.8 seconds to 10.8
Testing cloning with the EOL extension
$ cat >> $HGRCPATH <<EOF
> [extensions]
> eol =
>
> [eol]
> native = CRLF
> EOF
setup repository
$ hg init repo
$ cd repo
$ cat > .hgeol <<EOF
> [patterns]
> **.txt = native
> EOF
$ printf "first\r\nsecond\r\nthird\r\n" > a.txt
$ hg commit --addremove -m 'checkin'
adding .hgeol
adding a.txt
Clone
$ cd ..
$ hg clone repo repo-2
updating to branch default
2 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ cd repo-2
$ cat a.txt
first\r (esc)
second\r (esc)
third\r (esc)
$ hg cat a.txt
first
second
third
$ hg remove .hgeol
$ hg commit -m 'remove eol'
$ hg push --quiet
$ cd ..
Test clone of repo with .hgeol in working dir, but no .hgeol in tip
$ hg clone repo repo-3
updating to branch default
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ cd repo-3
$ cat a.txt
first
second
third
Test clone of revision with .hgeol
$ cd ..
$ hg clone -r 0 repo repo-4
adding changesets
adding manifests
adding file changes
added 1 changesets with 2 changes to 2 files
updating to branch default
2 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ cd repo-4
$ cat .hgeol
[patterns]
**.txt = native
$ cat a.txt
first\r (esc)
second\r (esc)
third\r (esc)
$ cd ..