merge tests: expect improved directory/file conflict handling in ort

merge-recursive.c is built on the idea of running unpack_trees() and
then "doing minor touch-ups" to get the result.  Unfortunately,
unpack_trees() was run in an update-as-it-goes mode, leading
merge-recursive.c to follow suit and end up with an immediate evaluation
and fix-it-up-as-you-go design.  Some things like directory/file
conflicts are not well representable in the index data structure, and
required special extra code to handle.  But then when it was discovered
that rename/delete conflicts could also be involved in directory/file
conflicts, the special directory/file conflict handling code had to be
copied to the rename/delete codepath.  ...and then it had to be copied
for modify/delete, and for rename/rename(1to2) conflicts, ...and yet it
still missed some.  Further, when it was discovered that there were also
file/submodule conflicts and submodule/directory conflicts, we needed to
copy the special submodule handling code to all the special cases
throughout the codebase.

And then it was discovered that our handling of directory/file conflicts
was suboptimal because it would create untracked files to store the
contents of the conflicting file, which would not be cleaned up if
someone were to run a 'git merge --abort' or 'git rebase --abort'.  It
was also difficult or scary to try to add or remove the index entries
corresponding to these files given the directory/file conflict in the
index.  But changing merge-recursive.c to handle these correctly was a
royal pain because there were so many sites in the code with similar but
not identical code for handling directory/file/submodule conflicts that
would all need to be updated.

I have worked hard to push all directory/file/submodule conflict
handling in merge-ort through a single codepath, and avoid creating
untracked files for storing tracked content (it does record things at
alternate paths, but makes sure they have higher-order stages in the
index).

Since updating merge-recursive is too much work and we don't want to
destabilize it, instead update the testsuite to have different
expectations for relevant directory/file/submodule conflict tests.

Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 12 insertions, 2 deletions

diff --git a/t/t6400-merge-df.sh b/t/t6400-merge-df.sh
index f1b84617af..9da0838216 100755
--- a/t/t6400-merge-df.sh
+++ b/t/t6400-merge-df.sh
@@ -81,7 +81,12 @@ test_expect_success 'modify/delete + directory/file conflict' '
 
 	test 5 -eq $(git ls-files -s | wc -l) &&
 	test 4 -eq $(git ls-files -u | wc -l) &&
-	test 1 -eq $(git ls-files -o | wc -l) &&
+	if test "$GIT_TEST_MERGE_ALGORITHM" = ort
+	then
+		test 0 -eq $(git ls-files -o | wc -l)
+	else
+		test 1 -eq $(git ls-files -o | wc -l)
+	fi &&
 
 	test_path_is_file letters/file &&
 	test_path_is_file letters.txt &&
@@ -97,7 +102,12 @@ test_expect_success 'modify/delete + directory/file conflict; other way' '
 
 	test 5 -eq $(git ls-files -s | wc -l) &&
 	test 4 -eq $(git ls-files -u | wc -l) &&
-	test 1 -eq $(git ls-files -o | wc -l) &&
+	if test "$GIT_TEST_MERGE_ALGORITHM" = ort
+	then
+		test 0 -eq $(git ls-files -o | wc -l)
+	else
+		test 1 -eq $(git ls-files -o | wc -l)
+	fi &&
 
 	test_path_is_file letters/file &&
 	test_path_is_file letters.txt &&