view tests/test-import.t @ 3843:f0096db2a7b1

evolve: improve error messages when conflicts occur

This patch improves the error messages when conflicts occur.

First, we drop the line 'evolution failed', that is not the best line we can
show and evolution didn't failed, it's just interrupted by the conflicts and
when user will run `hg evolve --continue`, things will be fine. I still remember
when I first saw 'evolution failed', I got a bit scare as am I in a recoverable
position or not. So let's drop this scary line.

Second, we replace the error messages to say `resolve conflicts and see
help-topic`. The help topic was added recently and documents all the three flags
very well. Addition of tests also showed that all the three flags works fine
with all the three instability type. So we should advertise them more.

Third, we now raise the error with our error message rather than raising
MergeFailure and having evolution related text in hint or stderr above. This
increase the focus on the error message we want to show.

After this patch, I think error messages by evolve in case of conflicts will be
same in every case.

This feature requires mercurial 3.0
(and the `only()` revset is 3.0 specific)

  $ (hg help revset | grep '"only(' > /dev/null) || exit 80

Test creation of obsolescence marker by path import

  $ hg init auto-obsolete
  $ cd auto-obsolete
  $ echo '[extensions]' >> $HGRCPATH
  $ echo "evolve=$(echo $(dirname $TESTDIR))/hgext3rd/evolve/" >> $HGRCPATH
  $ echo A > a
  $ hg commit -Am A
  adding a
  $ echo B > b
  $ hg commit -Am B
  adding b
  $ hg up '.^'
  0 files updated, 0 files merged, 1 files removed, 0 files unresolved
  $ echo C > c
  $ hg commit -Am C
  adding c
  created new head
  $ hg log -G
  @  changeset:   2:eb8dd0f31b51
  |  tag:         tip
  |  parent:      0:f2bbf19cf96d
  |  user:        test
  |  date:        Thu Jan 01 00:00:00 1970 +0000
  |  summary:     C
  |
  | o  changeset:   1:95b760afef3c
  |/   user:        test
  |    date:        Thu Jan 01 00:00:00 1970 +0000
  |    summary:     B
  |
  o  changeset:   0:f2bbf19cf96d
     user:        test
     date:        Thu Jan 01 00:00:00 1970 +0000
     summary:     A
  

(actual test)

  $ hg export 'desc(B)' | hg import - --obsolete
  applying patch from stdin
  $ hg log -G
  @  changeset:   3:00c49133f17e
  |  tag:         tip
  |  user:        test
  |  date:        Thu Jan 01 00:00:00 1970 +0000
  |  summary:     B
  |
  o  changeset:   2:eb8dd0f31b51
  |  parent:      0:f2bbf19cf96d
  |  user:        test
  |  date:        Thu Jan 01 00:00:00 1970 +0000
  |  summary:     C
  |
  o  changeset:   0:f2bbf19cf96d
     user:        test
     date:        Thu Jan 01 00:00:00 1970 +0000
     summary:     A
  
  $ hg debugobsolete
  95b760afef3c234ffb3f9fd391edcb36e60921a4 00c49133f17e5e5a52b6ef1b6d516c0e90b56d8a 0 (*) {'user': 'test'} (glob)

  $ hg rollback
  repository tip rolled back to revision 2 (undo import)
  working directory now based on revision 2
  $ hg log -G
  @  changeset:   2:eb8dd0f31b51
  |  tag:         tip
  |  parent:      0:f2bbf19cf96d
  |  user:        test
  |  date:        Thu Jan 01 00:00:00 1970 +0000
  |  summary:     C
  |
  | o  changeset:   1:95b760afef3c
  |/   user:        test
  |    date:        Thu Jan 01 00:00:00 1970 +0000
  |    summary:     B
  |
  o  changeset:   0:f2bbf19cf96d
     user:        test
     date:        Thu Jan 01 00:00:00 1970 +0000
     summary:     A
  
  $ hg debugobsolete