[PATCH 2/2] fast-export: remove now obsolete filtering of modified files

[Mark Nauwelaerts <mark.nauwelaerts@gmail.com>]

From: Mark Nauwelaerts <mnauw@users.sourceforge.net>

Revert b3e8ca8 ("fast-export: do not copy from modified file", 2017-09-20)
partially, since it is not necessary to filter out 'C' commands if the 'M'
and 'C' commands are in correct order.

The unit test that was added is kept around though, and it still passes
with this new approach.

Signed-off-by: Mark Nauwelaerts <mnauw@users.sourceforge.net>
---
 builtin/fast-export.c  | 46 ++++++++++++++--------------------------------
 t/t9350-fast-export.sh |  2 +-
 2 files changed, 15 insertions(+), 33 deletions(-)

diff --git a/builtin/fast-export.c b/builtin/fast-export.c
index 1b3e250..6aa4073 100644
--- a/builtin/fast-export.c
+++ b/builtin/fast-export.c
@@ -356,7 +356,6 @@ static void show_filemodify(struct diff_queue_struct *q,
 			    struct diff_options *options, void *data)
 {
 	int i;
-	struct string_list *changed = data;
 
 	/*
 	 * Handle files below a directory first, in case they are all deleted
@@ -372,31 +371,20 @@ static void show_filemodify(struct diff_queue_struct *q,
 		case DIFF_STATUS_DELETED:
 			printf("D ");
 			print_path(spec->path);
-			string_list_insert(changed, spec->path);
 			putchar('\n');
 			break;
 
 		case DIFF_STATUS_COPIED:
 		case DIFF_STATUS_RENAMED:
-			/*
-			 * If a change in the file corresponding to ospec->path
-			 * has been observed, we cannot trust its contents
-			 * because the diff is calculated based on the prior
-			 * contents, not the current contents.  So, declare a
-			 * copy or rename only if there was no change observed.
-			 */
-			if (!string_list_has_string(changed, ospec->path)) {
-				printf("%c ", q->queue[i]->status);
-				print_path(ospec->path);
-				putchar(' ');
-				print_path(spec->path);
-				string_list_insert(changed, spec->path);
-				putchar('\n');
-
-				if (!oidcmp(&ospec->oid, &spec->oid) &&
-				    ospec->mode == spec->mode)
-					break;
-			}
+			printf("%c ", q->queue[i]->status);
+			print_path(ospec->path);
+			putchar(' ');
+			print_path(spec->path);
+			putchar('\n');
+
+			if (!oidcmp(&ospec->oid, &spec->oid) &&
+			    ospec->mode == spec->mode)
+				break;
 			/* fallthrough */
 
 		case DIFF_STATUS_TYPE_CHANGED:
@@ -417,7 +405,6 @@ static void show_filemodify(struct diff_queue_struct *q,
 				       get_object_mark(object));
 			}
 			print_path(spec->path);
-			string_list_insert(changed, spec->path);
 			putchar('\n');
 			break;
 
@@ -553,8 +540,7 @@ static void anonymize_ident_line(const char **beg, const char **end)
 	*end = out->buf + out->len;
 }
 
-static void handle_commit(struct commit *commit, struct rev_info *rev,
-			  struct string_list *paths_of_changed_objects)
+static void handle_commit(struct commit *commit, struct rev_info *rev)
 {
 	int saved_output_format = rev->diffopt.output_format;
 	const char *commit_buffer;
@@ -641,7 +627,6 @@ static void handle_commit(struct commit *commit, struct rev_info *rev,
 	if (full_tree)
 		printf("deleteall\n");
 	log_tree_diff_flush(rev);
-	string_list_clear(paths_of_changed_objects, 0);
 	rev->diffopt.output_format = saved_output_format;
 
 	printf("\n");
@@ -657,15 +642,14 @@ static void *anonymize_tag(const void *old, size_t *len)
 	return strbuf_detach(&out, len);
 }
 
-static void handle_tail(struct object_array *commits, struct rev_info *revs,
-			struct string_list *paths_of_changed_objects)
+static void handle_tail(struct object_array *commits, struct rev_info *revs)
 {
 	struct commit *commit;
 	while (commits->nr) {
 		commit = (struct commit *)object_array_pop(commits);
 		if (has_unshown_parent(commit))
 			return;
-		handle_commit(commit, revs, paths_of_changed_objects);
+		handle_commit(commit, revs);
 	}
 }
 
@@ -1004,7 +988,6 @@ int cmd_fast_export(int argc, const char **argv, const char *prefix)
 	char *export_filename = NULL, *import_filename = NULL;
 	uint32_t lastimportid;
 	struct string_list refspecs_list = STRING_LIST_INIT_NODUP;
-	struct string_list paths_of_changed_objects = STRING_LIST_INIT_DUP;
 	struct option options[] = {
 		OPT_INTEGER(0, "progress", &progress,
 			    N_("show progress after <n> objects")),
@@ -1077,15 +1060,14 @@ int cmd_fast_export(int argc, const char **argv, const char *prefix)
 	if (prepare_revision_walk(&revs))
 		die("revision walk setup failed");
 	revs.diffopt.format_callback = show_filemodify;
-	revs.diffopt.format_callback_data = &paths_of_changed_objects;
 	DIFF_OPT_SET(&revs.diffopt, RECURSIVE);
 	while ((commit = get_revision(&revs))) {
 		if (has_unshown_parent(commit)) {
 			add_object_array(&commit->object, NULL, &commits);
 		}
 		else {
-			handle_commit(commit, &revs, &paths_of_changed_objects);
-			handle_tail(&commits, &revs, &paths_of_changed_objects);
+			handle_commit(commit, &revs);
+			handle_tail(&commits, &revs);
 		}
 	}
 
diff --git a/t/t9350-fast-export.sh b/t/t9350-fast-export.sh
index 866ddf6..06c66a1 100755
--- a/t/t9350-fast-export.sh
+++ b/t/t9350-fast-export.sh
@@ -522,7 +522,7 @@ test_expect_success 'delete refspec' '
 	test_cmp expected actual
 '
 
-test_expect_success 'when using -C, do not declare copy when source of copy is also modified' '
+test_expect_success 'when using -C, correctly order copy and modify of source of copy' '
 	test_create_repo src &&
 	echo a_line >src/file.txt &&
 	git -C src add file.txt &&
-- 
2.7.4