merge: additional test cases to show merge-halting behavior

In the previous patches, we allowed the user to specify that
a merge process should be halted when a filemerge fails.

This patch adds tests that show additional places this logic
can be utilized -- via the options to do additional post-filemerge
checks to determine if a file merge was successful.

Differential Revision: https://phab.mercurial-scm.org/D952

tests/test-merge-halt.t

@@ -1,79 +1,164 b''
   $ cat >> $HGRCPATH <<EOF
   > [extensions]
   > rebase=
   > [phases]
   > publish=False
   > [merge]
   > EOF
 
   $ hg init repo
   $ cd repo
   $ echo a > a
   $ echo b > b
   $ hg commit -qAm ab
   $ echo c >> a
   $ echo c >> b
   $ hg commit -qAm c
   $ hg up -q ".^"
   $ echo d >> a
   $ echo d >> b
   $ hg commit -qAm d
 
 Testing on-failure=continue
   $ echo on-failure=continue >> $HGRCPATH
   $ hg rebase -s 1 -d 2 --tool false
   rebasing 1:1f28a51c3c9b "c"
   merging a
   merging b
   merging a failed!
   merging b failed!
   unresolved conflicts (see hg resolve, then hg rebase --continue)
   [1]
 
   $ hg resolve --list
   U a
   U b
 
   $ hg rebase --abort
   rebase aborted
 
 Testing on-failure=halt
   $ echo on-failure=halt >> $HGRCPATH
   $ hg rebase -s 1 -d 2 --tool false
   rebasing 1:1f28a51c3c9b "c"
   merging a
   merging b
   merging a failed!
   merge halted after failed merge (see hg resolve)
   [1]
 
   $ hg resolve --list
   U a
   U b
 
   $ hg rebase --abort
   rebase aborted
 
 Testing on-failure=prompt
-  $ echo on-failure=prompt >> $HGRCPATH
-  $ cat <<EOS | hg rebase -s 1 -d 2 --tool false --config ui.interactive=1
+  $ cat <<EOS >> $HGRCPATH
+  > [merge]
+  > on-failure=prompt
+  > [ui]
+  > interactive=1
+  > EOS
+  $ cat <<EOS | hg rebase -s 1 -d 2 --tool false
   > y
   > n
   > EOS
   rebasing 1:1f28a51c3c9b "c"
   merging a
   merging b
   merging a failed!
   continue merge operation (yn)? y
   merging b failed!
   continue merge operation (yn)? n
   merge halted after failed merge (see hg resolve)
   [1]
 
   $ hg resolve --list
   U a
   U b
 
   $ hg rebase --abort
   rebase aborted
 
+Check that successful tool with failed post-check halts the merge
+  $ cat <<EOS >> $HGRCPATH
+  > [merge-tools]
+  > true.check=changed
+  > EOS
+  $ cat <<EOS | hg rebase -s 1 -d 2 --tool true
+  > y
+  > n
+  > n
+  > EOS
+  rebasing 1:1f28a51c3c9b "c"
+  merging a
+  merging b
+   output file a appears unchanged
+  was merge successful (yn)? y
+   output file b appears unchanged
+  was merge successful (yn)? n
+  merging b failed!
+  continue merge operation (yn)? n
+  merge halted after failed merge (see hg resolve)
+  [1]
+
+  $ hg resolve --list
+  R a
+  U b
+
+  $ hg rebase --abort
+  rebase aborted
+
+Check that conflicts with conflict check also halts the merge
+  $ cat <<EOS >> $HGRCPATH
+  > [merge-tools]
+  > true.check=conflicts
+  > true.premerge=keep
+  > [merge]
+  > on-failure=halt
+  > EOS
+  $ hg rebase -s 1 -d 2 --tool true
+  rebasing 1:1f28a51c3c9b "c"
+  merging a
+  merging b
+  merging a failed!
+  merge halted after failed merge (see hg resolve)
+  [1]
+
+  $ hg resolve --list
+  U a
+  U b
+
+  $ hg rebase --abort
+  rebase aborted
+
+Check that always-prompt also can halt the merge
+  $ cat <<EOS | hg rebase -s 1 -d 2 --tool true --config merge-tools.true.check=prompt
+  > y
+  > n
+  > EOS
+  rebasing 1:1f28a51c3c9b "c"
+  merging a
+  merging b
+  was merge of 'a' successful (yn)? y
+  was merge of 'b' successful (yn)? n
+  merging b failed!
+  merge halted after failed merge (see hg resolve)
+  [1]
+
+  $ hg resolve --list
+  R a
+  U b
+
+  $ hg rebase --abort
+  rebase aborted
+
+Check that successful tool otherwise allows the merge to continue
+  $ hg rebase -s 1 -d 2 --tool echo --keep --config merge-tools.echo.premerge=keep
+  rebasing 1:1f28a51c3c9b "c"
+  merging a
+  merging b
+  $TESTTMP/repo/a *a~base* *a~other* (glob)
+  $TESTTMP/repo/b *b~base* *b~other* (glob)