view tests/test-merge-default.out @ 10189:e451e599fbcf

patch: support diff data loss detection and upgrade

In worst case, generating diff in upgrade mode can be two times more expensive
than generating it in git mode directly: we may have to regenerate the whole
diff again whenever a git feature is detected. Also, the first diff attempt is
completely buffered instead of being streamed. That said, even without having
profiled it yet, I am convinced we can fast-path the upgrade mode if necessary
were it to be used in regular diff commands, and not only in mq where avoiding
data loss is worth the price.

adding a
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
created new head
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
created new head
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
% should fail because not at a head
abort: branch 'default' has 3 heads - please merge with an explicit rev
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
% should fail because > 2 heads
abort: branch 'default' has 3 heads - please merge with an explicit rev
% should succeed
0 files updated, 0 files merged, 0 files removed, 0 files unresolved
(branch merge, don't forget to commit)
% should succeed - 2 heads
changeset:   3:903c264cdf57
parent:      1:ba677d0156c1
user:        test
date:        Thu Jan 01 00:00:00 1970 +0000
summary:     d

0 files updated, 0 files merged, 0 files removed, 0 files unresolved
(branch merge, don't forget to commit)
% should fail because at tip
abort: there is nothing to merge
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
% should fail because 1 head
abort: there is nothing to merge - use "hg update" instead