Do not attempt to check out submodule as blob when merging a submodule modify/deltete conflict

src/checkout.c

@@ -2022,8 +2022,11 @@ static int checkout_write_entry(
 		(error = checkout_safe_for_update_only(data, fullpath->ptr, side->mode)) <= 0)
 		return error;
 
-	return checkout_write_content(data,
-		&side->id, fullpath->ptr, hint_path, side->mode, &st);
+	if (!S_ISGITLINK(side->mode))
+		return checkout_write_content(data,
+					      &side->id, fullpath->ptr, hint_path, side->mode, &st);
+
+	return 0;
 }
 
 static int checkout_write_entries(

tests/merge/workdir/submodules.c

@@ -12,6 +12,7 @@ static git_repository *repo;
 #define SUBMODULE_MAIN_BRANCH		"submodules"
 #define SUBMODULE_OTHER_BRANCH		"submodules-branch"
 #define SUBMODULE_OTHER2_BRANCH		"submodules-branch2"
+#define SUBMODULE_DELETE_BRANCH		"delete-submodule"
 
 #define TEST_INDEX_PATH TEST_REPO_PATH "/.git/index"
 
@@ -93,3 +94,38 @@ void test_merge_workdir_submodules__take_changed(void)
 	git_reference_free(their_ref);
 	git_reference_free(our_ref);
 }
+
+
+void test_merge_workdir_submodules__update_delete_conflict(void)
+{
+	git_reference *our_ref, *their_ref;
+	git_commit *our_commit;
+	git_annotated_commit *their_head;
+	git_index *index;
+
+	struct merge_index_entry merge_index_entries[] = {
+		{ 0100644, "e69de29bb2d1d6434b8b29ae775ad8c2e48c5391", 0, ".gitmodules" },
+		{ 0100644, "5887a5e516c53bd58efb0f02ec6aa031b6fe9ad7", 0, "file1.txt" },
+		{ 0100644, "4218670ab81cc219a9f94befb5c5dad90ec52648", 0, "file2.txt" },
+		{ 0160000, "d3d806a4bef96889117fd7ebac0e3cb5ec152932", 1, "submodule"},
+		{ 0160000, "297aa6cd028b3336c7802c7a6f49143da4e1602d", 3, "submodule" },
+	};
+
+	cl_git_pass(git_reference_lookup(&our_ref, repo, "refs/heads/" SUBMODULE_DELETE_BRANCH));
+	cl_git_pass(git_commit_lookup(&our_commit, repo, git_reference_target(our_ref)));
+	cl_git_pass(git_reset(repo, (git_object *)our_commit, GIT_RESET_HARD, NULL));
+
+	cl_git_pass(git_reference_lookup(&their_ref, repo, "refs/heads/" SUBMODULE_MAIN_BRANCH));
+	cl_git_pass(git_annotated_commit_from_ref(&their_head, repo, their_ref));
+
+	cl_git_pass(git_merge(repo, (const git_annotated_commit **)&their_head, 1, NULL, NULL));
+
+	cl_git_pass(git_repository_index(&index, repo));
+	cl_assert(merge_test_index(index, merge_index_entries, 5));
+
+	git_index_free(index);
+	git_annotated_commit_free(their_head);
+	git_commit_free(our_commit);
+	git_reference_free(their_ref);
+	git_reference_free(our_ref);
+}

tests/resources/merge-resolve/.gitted/objects/50/c5dc8cdfe40c688eb0a0e23be54dd57cae2e78

@@ -0,0 +1,2 @@
+x
<01>Ž]
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tests/resources/merge-resolve/.gitted/refs/heads/delete-submodule

@@ -0,0 +1 @@
+50c5dc8cdfe40c688eb0a0e23be54dd57cae2e78