Unit testing modal hide method

I've got a problem. I open new modal in my html file and close it inside angular controller with this call:

$(".modal-backdrop").hide();

And now, when it comes to unit-testing, I've got a problem, since I've got no idea how to test it. I tried to mock it in Unit testing $modal with Jasmine way, but my method doesn't really use obvious modal-id name. Can someone help me out?