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, 38 insertions, 15 deletions

diff --git a/t/t6423-merge-rename-directories.sh b/t/t6423-merge-rename-directories.sh
index 807a424a52..5ea77564d7 100755
--- a/t/t6423-merge-rename-directories.sh
+++ b/t/t6423-merge-rename-directories.sh
@@ -1177,10 +1177,18 @@ test_expect_success '5d: Directory/file/file conflict due to directory rename' '
 		git ls-files -u >out &&
 		test_line_count = 1 out &&
 		git ls-files -o >out &&
-		test_line_count = 2 out &&
-
-		git rev-parse >actual \
-			:0:y/b :0:y/c :0:z/d :0:y/f :2:y/d :0:y/d/e &&
+		if test "$GIT_TEST_MERGE_ALGORITHM" = ort
+		then
+			test_line_count = 1 out &&
+
+			git rev-parse >actual \
+			    :0:y/b :0:y/c :0:z/d :0:y/f :2:y/d~HEAD :0:y/d/e
+		else
+			test_line_count = 2 out &&
+
+			git rev-parse >actual \
+			    :0:y/b :0:y/c :0:z/d :0:y/f :2:y/d      :0:y/d/e
+		fi &&
 		git rev-parse >expect \
 			 O:z/b  O:z/c  B:z/d  B:z/f  A:y/d  B:y/d/e &&
 		test_cmp expect actual &&
@@ -2017,17 +2025,32 @@ test_expect_success '7e: transitive rename in rename/delete AND dirs in the way'
 		test_must_fail git -c merge.directoryRenames=true merge -s recursive B^0 >out &&
 		test_i18ngrep "CONFLICT (rename/delete).*x/d.*y/d" out &&
 
-		git ls-files -s >out &&
-		test_line_count = 5 out &&
-		git ls-files -u >out &&
-		test_line_count = 1 out &&
-		git ls-files -o >out &&
-		test_line_count = 2 out &&
-
-		git rev-parse >actual \
-			:0:x/d/f :0:y/d/g :0:y/b :0:y/c :3:y/d &&
-		git rev-parse >expect \
-			 A:x/d/f  A:y/d/g  O:z/b  O:z/c  O:x/d &&
+		if test "$GIT_TEST_MERGE_ALGORITHM" = ort
+		then
+			git ls-files -s >out &&
+			test_line_count = 6 out &&
+			git ls-files -u >out &&
+			test_line_count = 2 out &&
+			git ls-files -o >out &&
+			test_line_count = 1 out &&
+
+			git rev-parse >actual \
+				:0:x/d/f :0:y/d/g :0:y/b :0:y/c :1:y/d~B^0 :3:y/d~B^0 &&
+			git rev-parse >expect \
+				 A:x/d/f  A:y/d/g  O:z/b  O:z/c  O:x/d      O:x/d
+		else
+			git ls-files -s >out &&
+			test_line_count = 5 out &&
+			git ls-files -u >out &&
+			test_line_count = 1 out &&
+			git ls-files -o >out &&
+			test_line_count = 2 out &&
+
+			git rev-parse >actual \
+				:0:x/d/f :0:y/d/g :0:y/b :0:y/c :3:y/d &&
+			git rev-parse >expect \
+				 A:x/d/f  A:y/d/g  O:z/b  O:z/c  O:x/d
+		fi &&
 		test_cmp expect actual &&
 
 		git hash-object y/d~B^0 >actual &&