fullscreen/api/document-exit-fullscreen-nested-in-iframe.html

<!DOCTYPE html>
<title>Document#exitFullscreen() for nested fullscreen inside an iframe</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>
<iframe allowfullscreen></iframe>
<script>
    async function fullscreenNestedElements(t, iframe, outer, inner) {
        // First request fullscreen for the outer element.
        await Promise.all([fullScreenChange(), fullScreenChange(iframe.contentDocument), trusted_request(outer)]);
        assert_equals(document.fullscreenElement, iframe);
        assert_equals(iframe.contentDocument.fullscreenElement, outer);

        document.onfullscreenchange = t.unreached_func(
            "fullscreenchange event should not be emitted a second time for parent document."
        );

        // Then request fullscreen for the inner element.
        await Promise.all([fullScreenChange(iframe.contentDocument), trusted_request(inner)]);
        assert_equals(document.fullscreenElement, iframe);
        assert_equals(iframe.contentDocument.fullscreenElement, inner);

        document.onfullscreenchange = null;
    }

    promise_test(async (t) => {
        const iframe = document.querySelector("iframe");
        await new Promise((resolve) => {
            iframe.onload = resolve;
            iframe.srcdoc = "<div id='outer'><div id='inner'></div></div>";
        });

        const iframeDoc = iframe.contentDocument;
        const outer = iframeDoc.getElementById("outer");
        const inner = iframeDoc.getElementById("inner");

        // Fullscreen outer, then inner, 2 elements in toplayer of <iframe>
        await fullscreenNestedElements(t, iframe, outer, inner);

        // Check if iframe sees (fullscreenchange, element) as per spec
        await Promise.all([fullScreenChange(iframeDoc), iframeDoc.exitFullscreen()]);

        // First iframe.contentDocument.exitFullscreen()
        // should only remove 1 from the top layer of iframe
        assert_equals(iframeDoc.fullscreenElement, outer);
        assert_equals(document.fullscreenElement, iframe);
        // Second exitFullscreen should exit fully from fullscreen, as stated by
        // https://fullscreen.spec.whatwg.org/#collect-documents-to-unfullscreen, since
        // all documents are now simple fullscreen documents
        // https://fullscreen.spec.whatwg.org/#simple-fullscreen-document
        await Promise.all([fullScreenChange(document), iframeDoc.exitFullscreen()]);
        assert_equals(iframeDoc.fullscreenElement, null);
        assert_equals(document.fullscreenElement, null);

        await fullscreenNestedElements(t, iframe, outer, inner);

        // Exit the top level document from fullscreen - should exit all documents below it as
        // per step 13 & 15 in https://fullscreen.spec.whatwg.org/#exit-fullscreen
        await Promise.all([fullScreenChange(document), document.exitFullscreen()]);
        assert_equals(iframeDoc.fullscreenElement, null);
        assert_equals(document.fullscreenElement, null);
    }, "Exit fullscreen for nested fullscreen inside an iframe");
</script>