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, 22 insertions, 8 deletions

diff --git a/t/t6422-merge-rename-corner-cases.sh b/t/t6422-merge-rename-corner-cases.sh
index 58729593ba..78bfaf17f0 100755
--- a/t/t6422-merge-rename-corner-cases.sh
+++ b/t/t6422-merge-rename-corner-cases.sh
@@ -313,15 +313,18 @@ test_expect_success 'rename/directory conflict + clean content merge' '
 		git ls-files -u >out &&
 		test_line_count = 1 out &&
 		git ls-files -o >out &&
-		test_line_count = 2 out &&
+		if test "$GIT_TEST_MERGE_ALGORITHM" = ort
+		then
+			test_line_count = 1 out
+		else
+			test_line_count = 2 out
+		fi &&
 
 		echo 0 >expect &&
 		git cat-file -p base:file >>expect &&
 		echo 7 >>expect &&
 		test_cmp expect newfile~HEAD &&
 
-		test $(git rev-parse :2:newfile) = $(git hash-object expect) &&
-
 		test_path_is_file newfile/realfile &&
 		test_path_is_file newfile~HEAD
 	)
@@ -344,7 +347,12 @@ test_expect_success 'rename/directory conflict + content merge conflict' '
 		git ls-files -u >out &&
 		test_line_count = 3 out &&
 		git ls-files -o >out &&
-		test_line_count = 2 out &&
+		if test "$GIT_TEST_MERGE_ALGORITHM" = ort
+		then
+			test_line_count = 1 out
+		else
+			test_line_count = 2 out
+		fi &&
 
 		git cat-file -p left-conflict:newfile >left &&
 		git cat-file -p base:file    >base &&
@@ -356,10 +364,16 @@ test_expect_success 'rename/directory conflict + content merge conflict' '
 			left base right &&
 		test_cmp left newfile~HEAD &&
 
-		git rev-parse >expect                                 \
-			base:file   left-conflict:newfile  right:file &&
-		git rev-parse >actual                                 \
-			:1:newfile  :2:newfile             :3:newfile &&
+		git rev-parse >expect   \
+			base:file       left-conflict:newfile right:file &&
+		if test "$GIT_TEST_MERGE_ALGORITHM" = ort
+		then
+			git rev-parse >actual \
+				:1:newfile~HEAD :2:newfile~HEAD :3:newfile~HEAD
+		else
+			git rev-parse >actual \
+				:1:newfile      :2:newfile      :3:newfile
+		fi &&
 		test_cmp expect actual &&
 
 		test_path_is_file newfile/realfile &&