t6429: remove switching aspects of fast-rebase

At the time t6429 was written, merge-ort was still under development,
did not have quite as many tests, and certainly was not widely deployed.
Since t6429 was exercising some codepaths just a little differently, we
thought having them also test the "merge_switch_to_result()" bits of
merge-ort was useful even though they weren't intrinsic to the real
point of these tests.

However, the value provided by doing extra testing of the
"merge_switch_to_result()" bits has decreased a bit over time, and it's
actively making it harder to refactor `test-tool fast-rebase` into `git
replay`, which we are going to do in following commits.  Dispense with
these bits.

Co-authored-by: Christian Couder <[email protected]>
Signed-off-by: Elijah Newren <[email protected]>
Signed-off-by: Christian Couder <[email protected]>
Signed-off-by: Junio C Hamano <[email protected]>

Author: 2 people

t/helper/test-fast-rebase.c

@@ -194,7 +194,7 @@ int cmd__fast_rebase(int argc, const char **argv)
 		last_commit = create_commit(result.tree, commit, last_commit);
 	}
 
-	merge_switch_to_result(&merge_opt, head_tree, &result, 1, !result.clean);
+	merge_finalize(&merge_opt, &result);
 
 	if (result.clean < 0)
 		exit(128);
@@ -213,9 +213,6 @@ int cmd__fast_rebase(int argc, const char **argv)
 		}
 		if (create_symref("HEAD", branch_name.buf, reflog_msg.buf) < 0)
 			die(_("unable to update HEAD"));
-
-		prime_cache_tree(the_repository, the_repository->index,
-				 result.tree);
 	} else {
 		fprintf(stderr, "\nAborting: Hit a conflict.\n");
 		strbuf_addf(&reflog_msg, "rebase progress up to %s",
@@ -228,10 +225,6 @@ int cmd__fast_rebase(int argc, const char **argv)
 			die("Failed to update %s", argv[4]);
 		}
 	}
-	if (write_locked_index(&the_index, &lock,
-			       COMMIT_LOCK | SKIP_IF_UNCHANGED))
-		die(_("unable to write %s"), get_index_file());
-
 	ret = (result.clean == 0);
 cleanup:
 	strbuf_release(&reflog_msg);

t/t6429-merge-sequence-rename-caching.sh

@@ -72,6 +72,7 @@ test_expect_success 'caching renames does not preclude finding new ones' '
 		git switch upstream &&
 
 		test-tool fast-rebase --onto HEAD upstream~1 topic &&
+		git reset --hard topic &&
 		#git cherry-pick upstream~1..topic
 
 		git ls-files >tracked-files &&
@@ -200,6 +201,7 @@ test_expect_success 'rename same file identically, then reintroduce it' '
 		export GIT_TRACE2_PERF &&
 
 		test-tool fast-rebase --onto HEAD upstream~1 topic &&
+		git reset --hard topic &&
 		#git cherry-pick upstream~1..topic &&
 
 		git ls-files >tracked &&
@@ -277,6 +279,7 @@ test_expect_success 'rename same file identically, then add file to old dir' '
 		export GIT_TRACE2_PERF &&
 
 		test-tool fast-rebase --onto HEAD upstream~1 topic &&
+		git reset --hard topic &&
 		#git cherry-pick upstream~1..topic &&
 
 		git ls-files >tracked &&
@@ -356,8 +359,6 @@ test_expect_success 'cached dir rename does not prevent noticing later conflict'
 		test_must_fail test-tool fast-rebase --onto HEAD upstream~1 topic >output &&
 		#git cherry-pick upstream..topic &&
 
-		grep CONFLICT..rename/rename output &&
-
 		grep region_enter.*diffcore_rename trace.output >calls &&
 		test_line_count = 2 calls
 	)
@@ -456,6 +457,7 @@ test_expect_success 'dir rename unneeded, then add new file to old dir' '
 		export GIT_TRACE2_PERF &&
 
 		test-tool fast-rebase --onto HEAD upstream~1 topic &&
+		git reset --hard topic &&
 		#git cherry-pick upstream..topic &&
 
 		grep region_enter.*diffcore_rename trace.output >calls &&
@@ -522,6 +524,7 @@ test_expect_success 'dir rename unneeded, then rename existing file into old dir
 		export GIT_TRACE2_PERF &&
 
 		test-tool fast-rebase --onto HEAD upstream~1 topic &&
+		git reset --hard topic &&
 		#git cherry-pick upstream..topic &&
 
 		grep region_enter.*diffcore_rename trace.output >calls &&
@@ -624,6 +627,7 @@ test_expect_success 'caching renames only on upstream side, part 1' '
 		export GIT_TRACE2_PERF &&
 
 		test-tool fast-rebase --onto HEAD upstream~1 topic &&
+		git reset --hard topic &&
 		#git cherry-pick upstream..topic &&
 
 		grep region_enter.*diffcore_rename trace.output >calls &&
@@ -682,6 +686,7 @@ test_expect_success 'caching renames only on upstream side, part 2' '
 		export GIT_TRACE2_PERF &&
 
 		test-tool fast-rebase --onto HEAD upstream~1 topic &&
+		git reset --hard topic &&
 		#git cherry-pick upstream..topic &&
 
 		grep region_enter.*diffcore_rename trace.output >calls &&