<!DOCTYPE html>

<html>
<head>
    <script src="../../../resources/js-test-pre.js"></script>
    <script>
        
        var jsTestIsAsync = true;
        
        function getAsyncTaskScript()
        {
            return `(function() {
                uiController.didEndScrollingCallback = function() { };
                uiController.didEndScrollingCallback = undefined;

                uiController.doAsyncTask(function() {
                    uiController.uiScriptComplete('async task complete');
                });
            })();`;
        }

        function getImmediateScript()
        {
            return `(function() {
                return 'immediate script complete';
            })();`;
        }
    
        var scriptResult;
        function runTest()
        {
            description('Test that a second immediate UI script returns if an earlier script registered then unregistered a callback');

            if (!window.testRunner) {
                debug('This test requires testRunner');
                return;
            }

            if (!testRunner.runUIScript) {
                debug('This test requires runUIScript');
                return;
            }

            testRunner.runUIScript(getAsyncTaskScript(), function(result) {
                scriptResult = result;
                shouldBeEqualToString('scriptResult', 'async task complete');

                testRunner.runUIScript(getImmediateScript(), function(result) {
                    scriptResult = result;
                    shouldBeEqualToString('scriptResult', 'immediate script complete');
                    finishJSTest();
                });
            });
        }
        window.addEventListener('load', runTest, false);
    </script>
</head>
<body>

<pre id="results"></pre>
<script src="../../../resources/js-test-post.js"></script>
</body>
</html>