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<title>Test MediaRecorder Immediate Stop</title>
<script src="/tests/SimpleTest/SimpleTest.js"></script>
<link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css" />
<script type="text/javascript" src="manifest.js"></script>
<pre id="test">
<script class="testbody" type="text/javascript">
var manager = new MediaTestManager;
* Stops the media recorder immediately after starting the recorder. This test
* verifies whether the media recorder can handle this scenario nicely. The
* return blob size should be greater than zero, but its duration would be zero
* length when play.
function startTest(test, token) {
var element = document.createElement('audio');
var expectedMimeType = test.type;
element.token = token;
element.src =;
element.test = test; = element.mozCaptureStreamUntilEnded();
var mediaRecorder =
new MediaRecorder(, {mimeType: expectedMimeType});
var onStopFired = false;
var onDataAvailableFired = false;
mediaRecorder.onerror = function () {
ok(false, 'Unexpected onerror callback fired');
mediaRecorder.onwarning = function () {
ok(false, 'Unexpected onwarning callback fired');
// This handler verifies that only a single onstop event handler is fired.
mediaRecorder.onstop = function () {
if (onStopFired) {
ok(false, 'onstop unexpectedly fired more than once');
} else {
onStopFired = true;
// ondataavailable should always fire before onstop
if (onDataAvailableFired) {
} else {
ok(false, 'onstop fired without an ondataavailable event first');
// This handler verifies that only a single ondataavailable event handler
// is fired with the blob generated having greater than zero size
// and a correct mime type.
mediaRecorder.ondataavailable = function (evt) {
if (onDataAvailableFired) {
ok(false, 'ondataavailable unexpectedly fired more than once');
} else {
onDataAvailableFired = true;
ok(evt instanceof BlobEvent,
'Events fired from ondataavailable should be BlobEvent');
is(evt.type, 'dataavailable',
'Event type should dataavailable');
// The initialization of encoder can be cancelled.
// On some platforms, the stop method may run after media stream track
// available, so the blob can contain the header data.
is(, expectedMimeType,
'Blob data received and should have mime type');
is(mediaRecorder.mimeType, expectedMimeType,
'Media Recorder mime type in ondataavailable = ' + expectedMimeType);
ok( >= 0, 'Blob size can not be negative');
// onstop should not have fired before ondataavailable
if (onStopFired) {
ok(false, 'ondataavailable unexpectedly fired later than onstop');
// This handler completes a start and stop of recording and verifies
// respective media recorder state.
element.onloadedmetadata = function () {
element.onloadedmetadata = null;;
is(mediaRecorder.state, 'recording', 'Media recorder should be recording');
'Media recorder stream = element stream at the start of recording');
is(mediaRecorder.state, 'inactive',
'Media recorder is inactive after being stopped');
'Media recorder stream = element stream post recording');
element.preload = "metadata";
manager.runTests(gMediaRecorderTests, startTest);