view tests/test-merge-closedheads.out @ 8849:80cc4b1a62d0

compare grep result between target and its parent

I found that typical case is that grep target is added at (*) revision
in the tree shown below.

     +--- 1(*) --- 3
     0
     +--- 2 ------ 4

Now, I expect 'hg grep --all' to show only rev:1 which is first
appearance of target line.

But 'hg grep --all' will tell:

  target line dis-appeared at 3 => 4
  target line     appeared at 2 => 3
  target line dis-appeared at 1 => 2
  target line     appeared at 0 => 1

because current 'hg grep' implementation compares not between target
revision and its parent, but between neighbor revisions in walkthrough
order.

I checked performance of this patch by "hg grep --follow --all
walkchangerevs" on whole Mercurial repo, and patched version could
complete as fast as un-patched one.

adding foo
adding bar
adding baz
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
created new head
0 files updated, 0 files merged, 1 files removed, 0 files unresolved
created new head
% fail with three heads
0 files updated, 0 files merged, 0 files removed, 0 files unresolved
abort: branch 'default' has 3 heads - please merge with an explicit rev
% close one of the heads
1 files updated, 0 files merged, 1 files removed, 0 files unresolved
% succeed with two open heads
1 files updated, 0 files merged, 1 files removed, 0 files unresolved
0 files updated, 0 files merged, 0 files removed, 0 files unresolved
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
(branch merge, don't forget to commit)