<html>
<head>
<script>
function debug(str) {
    var c = document.getElementById('console')
    c.innerHTML += (str + "<br>")
}

function runTests() {
    if (window.testRunner)
        testRunner.dumpAsText();
        
    debug('document.all: ' + document.all)
    
    if (document.all) {
        debug('FAILURE: document.all should evaluate to false')
        return;
    }

    if (!document.all) {
        // Do nothing
    } else {
        debug('FAILURE: document.all should evaluate to false')
        return;
    }
    if (document.all != undefined) {
        debug('FAILURE: document.all != undefined should evaluate to false ')
        return;
    }

    if (undefined != document.all) {
        debug('FAILURE: undefined != document.all should evaluate to false ')
        return;
    }

    if (document.all != null) {
        debug('FAILURE: document.all != null should evaluate to false')
        return;
    }

    if (null != document.all) {
        debug('FAILURE: null != document.all should evaluate to false')
        return;
    }
    
    // Try replacing document.all with something else
    document.all = { 'foo': 42}
    
    if (document.all.foo == 42) {
        debug('FAILURE: document.all should be read-only');
        return;
    }

    // Delete new document.all 
    delete(document.all)
    
    if (document.all.foo != undefined) {
        debug('FAILURE: deleting replace document.all did not work')
        return;
    }
    
    // Check typeof document.all
    if (typeof document.all != 'undefined') {
        debug('FAILURE: typeof document.all should be undefined');
        return;
    }

    debug('SUCCESS!')
}
</script>
</head>
<body onload="runTests();">
This tests that document.all should be undetectable, and that it should be possible to delete document.all. If this test is successful, the text "SUCCESS" should be shown below.
<pre id="console"></pre>
</body>
</html>