<!DOCTYPE html>
<title>Document#exitFullscreen() called twice</title>
<script src="/resources/testharness.js"></script>
<script src="/resources/testharnessreport.js"></script>
<script src="/resources/testdriver.js"></script>
<script src="/resources/testdriver-vendor.js"></script>
<script src="../trusted-click.js"></script>
<div id="log"></div>
<script>
    promise_test(async (t) => {
        const once = { once: true };
        const div = document.querySelector("div");
        document.onfullscreenerror = t.unreached_func("fullscreenerror event");

        await Promise.all([
            fullScreenChange(),
            trusted_request(div),
        ]);

        // We are now in fullscreen.
        assert_equals(document.fullscreenElement, div);

        // Exit fullscreen twice.
        const firstPromise = document.exitFullscreen();
        assert_equals(
            document.fullscreenElement,
            div,
            "fullscreenElement after first exitFullscreen()"
        );

        const secondPromise = document.exitFullscreen();
        assert_equals(
            document.fullscreenElement,
            div,
            "fullscreenElement after second exitFullscreen()"
        );
        const eventChange = new Promise((resolve) => {
            document.addEventListener("fullscreenchange", resolve, once);
            document.addEventListener(
                "fullscreenchange",
                t.unreached_func("second event fired"),
                once
            );
        });

        await Promise.all([
            fullScreenChange,
            firstPromise,
            secondPromise,
            eventChange,
        ]);
        assert_equals(document.fullscreenElement, null);
    });
</script>
