Merge branch 'jk/diff-result-code-cleanup' into maint-2.42

"git diff --no-such-option" and other corner cases around the exit
status of the "diff" command has been corrected.

* jk/diff-result-code-cleanup:
  diff: drop useless "status" parameter from diff_result_code()
  diff: drop useless return values in git-diff helpers
  diff: drop useless return from run_diff_{files,index} functions
  diff: die when failing to read index in git-diff builtin
  diff: show usage for unknown builtin_diff_files() options
  diff-files: avoid negative exit value
  diff: spell DIFF_INDEX_CACHED out when calling run_diff_index()

1 files changed, 6 insertions, 10 deletions

diff --git a/builtin/stash.c b/builtin/stash.c
index fe64cde9ce..53e8868ba1 100644
--- a/builtin/stash.c
+++ b/builtin/stash.c
@@ -973,7 +973,7 @@ static int show_stash(int argc, const char **argv, const char *prefix)
 	}
 	log_tree_diff_flush(&rev);
 
-	ret = diff_result_code(&rev.diffopt, 0);
+	ret = diff_result_code(&rev.diffopt);
 cleanup:
 	strvec_clear(&stash_args);
 	free_stash_info(&info);
@@ -1089,7 +1089,6 @@ static int get_untracked_files(const struct pathspec *ps, int include_untracked,
  */
 static int check_changes_tracked_files(const struct pathspec *ps)
 {
-	int result;
 	struct rev_info rev;
 	struct object_id dummy;
 	int ret = 0;
@@ -1111,14 +1110,14 @@ static int check_changes_tracked_files(const struct pathspec *ps)
 	add_head_to_pending(&rev);
 	diff_setup_done(&rev.diffopt);
 
-	result = run_diff_index(&rev, 1);
-	if (diff_result_code(&rev.diffopt, result)) {
+	run_diff_index(&rev, DIFF_INDEX_CACHED);
+	if (diff_result_code(&rev.diffopt)) {
 		ret = 1;
 		goto done;
 	}
 
-	result = run_diff_files(&rev, 0);
-	if (diff_result_code(&rev.diffopt, result)) {
+	run_diff_files(&rev, 0);
+	if (diff_result_code(&rev.diffopt)) {
 		ret = 1;
 		goto done;
 	}
@@ -1309,10 +1308,7 @@ static int stash_working_tree(struct stash_info *info, const struct pathspec *ps
 
 	add_pending_object(&rev, parse_object(the_repository, &info->b_commit),
 			   "");
-	if (run_diff_index(&rev, 0)) {
-		ret = -1;
-		goto done;
-	}
+	run_diff_index(&rev, 0);
 
 	cp_upd_index.git_cmd = 1;
 	strvec_pushl(&cp_upd_index.args, "update-index",