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
$ hgcommit() {
> hg commit -u user "$@"
> }
$ hg init clhead
$ cd clhead
$ touch foo && hg add && hgcommit -m 'foo'
adding foo
$ touch bar && hg add && hgcommit -m 'bar'
adding bar
$ touch baz && hg add && hgcommit -m 'baz'
adding baz
$ echo "flub" > foo
$ hgcommit -m "flub"
$ echo "nub" > foo
$ hgcommit -m "nub"
$ hg up -C 2
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ echo "c1" > c1
$ hg add c1
$ hgcommit -m "c1"
created new head
$ echo "c2" > c1
$ hgcommit -m "c2"
$ hg up -C 2
0 files updated, 0 files merged, 1 files removed, 0 files unresolved
$ echo "d1" > d1
$ hg add d1
$ hgcommit -m "d1"
created new head
$ echo "d2" > d1
$ hgcommit -m "d2"
$ hg tag -l good
fail with three heads
$ hg up -C good
0 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ hg merge
abort: branch 'default' has 3 heads - please merge with an explicit rev
(run 'hg heads .' to see heads)
[255]
close one of the heads
$ hg up -C 6
1 files updated, 0 files merged, 1 files removed, 0 files unresolved
$ hgcommit -m 'close this head' --close-branch
succeed with two open heads
$ hg up -C good
1 files updated, 0 files merged, 1 files removed, 0 files unresolved
$ hg up -C good
0 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ hg merge
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
(branch merge, don't forget to commit)
$ hgcommit -m 'merged heads'
hg update -C 8
$ hg update -C 8
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
hg branch some-branch
$ hg branch some-branch
marked working directory as branch some-branch
(branches are permanent and global, did you want a bookmark?)
hg commit
$ hgcommit -m 'started some-branch'
hg commit --close-branch
$ hgcommit --close-branch -m 'closed some-branch'
hg update default
$ hg update default
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
hg merge some-branch
$ hg merge some-branch
0 files updated, 0 files merged, 0 files removed, 0 files unresolved
(branch merge, don't forget to commit)
hg commit (no reopening of some-branch)
$ hgcommit -m 'merge with closed branch'
$ cd ..