submodule: skip redundant active entries when pattern covers path

configure_added_submodule always writes an explicit
submodule.<name>.active entry, even when the new
path is already matched by submodule.active
patterns. This leads to unnecessary and cluttered configuration.

change the logic to centralize wildmatch-based pattern lookup,
in configure_added_submodule. Wrap the active-entry write in a conditional
that only fires when that helper reports no existing pattern covers the
submodule’s path.

Signed-off-by: K Jayatheerth <jayatheerthkulkarni2005@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

Author: jayatheerthkulkarni

builtin/submodule--helper.c

@@ -32,6 +32,8 @@
 #include "advice.h"
 #include "branch.h"
 #include "list-objects-filter-options.h"
+#include "wildmatch.h"
+#include "strbuf.h"
 
 #define OPT_QUIET (1 << 0)
 #define OPT_CACHED (1 << 1)
@@ -3329,6 +3331,9 @@ static void configure_added_submodule(struct add_data *add_data)
 	struct child_process add_submod = CHILD_PROCESS_INIT;
 	struct child_process add_gitmodules = CHILD_PROCESS_INIT;
 
+	const struct string_list *values;
+	size_t i;
+	int matched = 0;
 	key = xstrfmt("submodule.%s.url", add_data->sm_name);
 	git_config_set_gently(key, add_data->realrepo);
 	free(key);
@@ -3370,20 +3375,28 @@ static void configure_added_submodule(struct add_data *add_data)
 	 * is_submodule_active(), since that function needs to find
 	 * out the value of "submodule.active" again anyway.
 	 */
-	if (!git_config_get("submodule.active")) {
+	if (git_config_get("submodule.active") || /* key absent */
+	    git_config_get_string_multi("submodule.active", &values)) {
 		/*
 		 * If the submodule being added isn't already covered by the
 		 * current configured pathspec, set the submodule's active flag
 		 */
-		if (!is_submodule_active(the_repository, add_data->sm_path)) {
+		key = xstrfmt("submodule.%s.active", add_data->sm_name);
+		git_config_set_gently(key, "true");
+		free(key);
+	} else {
+		for (i = 0; i < values->nr; i++) {
+			const char *pat = values->items[i].string;
+			if (!wildmatch(pat, add_data->sm_path, 0)) { /* match found */
+				matched = 1;
+				break;
+			}
+		}
+		if (!matched) { /* no pattern matched -> force-enable */
 			key = xstrfmt("submodule.%s.active", add_data->sm_name);
 			git_config_set_gently(key, "true");
 			free(key);
 		}
-	} else {
-		key = xstrfmt("submodule.%s.active", add_data->sm_name);
-		git_config_set_gently(key, "true");
-		free(key);
 	}
 }
 

t/t7413-submodule-is-active.sh

@@ -124,4 +124,19 @@ test_expect_success 'is-active, submodule.active and submodule add' '
 	git -C super2 config --get submodule.mod.active
 '
 
+test_expect_success 'submodule add skips redundant active entry' '
+	git init repo &&
+	(
+		cd repo &&
+		git config submodule.active "lib/*" &&
+		git commit --allow-empty -m init &&
+
+		git init ../lib-origin &&
+		git -C ../lib-origin commit --allow-empty -m init &&
+
+		git submodule add ../lib-origin lib/foo &&
+		test_must_fail git config --get submodule.lib/foo.active
+	)
+'
+
 test_done