dir.c: free removed sparse-pattern hashmap entries

In add_pattern_to_hashsets(), we remove entries from the
recursive_hashmap when adding similar ones to the parent_hashmap. I
won't pretend to understand all of what's going on here, but there's an
obvious leak: whatever we removed from recursive_hashmap is not
referenced anywhere else, and is never free()d.

We can easily fix this by asking the hashmap to return a pointer to the
old entry. This makes t7002 now completely leak-free.

Signed-off-by: Jeff King <[email protected]>
Signed-off-by: Junio C Hamano <[email protected]>

Author: peff

dir.c

@@ -810,6 +810,8 @@ static void add_pattern_to_hashsets(struct pattern_list *pl, struct path_pattern
 
 	if (given->patternlen > 2 &&
 	    !strcmp(given->pattern + given->patternlen - 2, "/*")) {
+		struct pattern_entry *old;
+
 		if (!(given->flags & PATTERN_FLAG_NEGATIVE)) {
 			/* Not a cone pattern. */
 			warning(_("unrecognized pattern: '%s'"), given->pattern);
@@ -835,7 +837,11 @@ static void add_pattern_to_hashsets(struct pattern_list *pl, struct path_pattern
 		}
 
 		hashmap_add(&pl->parent_hashmap, &translated->ent);
-		hashmap_remove(&pl->recursive_hashmap, &translated->ent, &data);
+		old = hashmap_remove_entry(&pl->recursive_hashmap, translated, ent, &data);
+		if (old) {
+			free(old->pattern);
+			free(old);
+		}
 		free(data);
 		return;
 	}

t/t7002-mv-sparse-checkout.sh

@@ -2,6 +2,7 @@
 
 test_description='git mv in sparse working trees'
 
+TEST_PASSES_SANITIZE_LEAK=true
 . ./test-lib.sh
 
 setup_sparse_checkout () {