function testMissingUpdate() {
$starting_updates = array(
'update_test_2' => 8000,
);
$update_graph = update_resolve_dependencies($starting_updates);
$this
->assertTrue($update_graph['update_test_2_update_8000']['allowed'], "The module's first update function is allowed to run, since it does not have any missing dependencies.");
$this
->assertFalse($update_graph['update_test_2_update_8001']['allowed'], "The module's second update function is not allowed to run, since it has a direct dependency on a missing update.");
$this
->assertFalse($update_graph['update_test_2_update_8002']['allowed'], "The module's third update function is not allowed to run, since it has an indirect dependency on a missing update.");
}