worktree: fix a trivial leak in prune_worktrees()

We were leaking both the "struct strbuf" in prune_worktrees(), as well
as the "path" we got from should_prune_worktree(). Since these were
the only two uses of the "struct string_list" let's change it to a
"DUP" and push these to it with "string_list_append_nodup()".

For the string_list_append_nodup() we could also string_list_append()
the main_path.buf, and then strbuf_release(&main_path) right away. But
doing it this way avoids an allocation, as we already have the "struct
strbuf" prepared for appending to "kept".

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

builtin/worktree.c

@@ -173,7 +173,7 @@ static void prune_worktrees(void)
 {
 	struct strbuf reason = STRBUF_INIT;
 	struct strbuf main_path = STRBUF_INIT;
-	struct string_list kept = STRING_LIST_INIT_NODUP;
+	struct string_list kept = STRING_LIST_INIT_DUP;
 	DIR *dir = opendir(git_path("worktrees"));
 	struct dirent *d;
 	if (!dir)
@@ -184,14 +184,14 @@ static void prune_worktrees(void)
 		if (should_prune_worktree(d->d_name, &reason, &path, expire))
 			prune_worktree(d->d_name, reason.buf);
 		else if (path)
-			string_list_append(&kept, path)->util = xstrdup(d->d_name);
+			string_list_append_nodup(&kept, path)->util = xstrdup(d->d_name);
 	}
 	closedir(dir);
 
 	strbuf_add_absolute_path(&main_path, get_git_common_dir());
 	/* massage main worktree absolute path to match 'gitdir' content */
 	strbuf_strip_suffix(&main_path, "/.");
-	string_list_append(&kept, strbuf_detach(&main_path, NULL));
+	string_list_append_nodup(&kept, strbuf_detach(&main_path, NULL));
 	prune_dups(&kept);
 	string_list_clear(&kept, 1);
 

t/t2401-worktree-prune.sh

@@ -5,6 +5,7 @@ test_description='prune $GIT_DIR/worktrees'
 GIT_TEST_DEFAULT_INITIAL_BRANCH_NAME=main
 export GIT_TEST_DEFAULT_INITIAL_BRANCH_NAME
 
+TEST_PASSES_SANITIZE_LEAK=true
 . ./test-lib.sh
 
 test_expect_success initialize '

t/t2406-worktree-repair.sh

@@ -2,6 +2,7 @@
 
 test_description='test git worktree repair'
 
+TEST_PASSES_SANITIZE_LEAK=true
 . ./test-lib.sh
 
 test_expect_success setup '