commit-reach: fix memory leak in ahead_behind()

We use a priority queue in `ahead_behind()` to compute the ahead/behind
count for commits. We may not iterate through all commits part of that
queue though in case all of its entries are stale. Consequently, as we
never make the effort to release the remaining commits, we end up
leaking bit arrays that we have allocated for each of the contained
commits.

Plug this leak and mark the corresponding test as leak free.

Signed-off-by: Patrick Steinhardt <[email protected]>
Signed-off-by: Junio C Hamano <[email protected]>

Author: pks-t

commit-reach.c

@@ -1106,6 +1106,10 @@ void ahead_behind(struct repository *r,
 
 	/* STALE is used here, PARENT2 is used by insert_no_dup(). */
 	repo_clear_commit_marks(r, PARENT2 | STALE);
+	while (prio_queue_peek(&queue)) {
+		struct commit *c = prio_queue_get(&queue);
+		free_bit_array(c);
+	}
 	clear_bit_arrays(&bit_arrays);
 	clear_prio_queue(&queue);
 }

t/t3203-branch-output.sh

@@ -1,6 +1,8 @@
 #!/bin/sh
 
 test_description='git branch display tests'
+
+TEST_PASSES_SANITIZE_LEAK=true
 . ./test-lib.sh
 . "$TEST_DIRECTORY"/lib-terminal.sh