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Test Info: Warnings
- This test has a WPT meta file that expects 6 subtest issues.
- This WPT test may be referenced by the following Test IDs:
- /webrtc/simulcast/negotiation-encodings.https.html - WPT Dashboard Interop Dashboard
<!doctype html>
<meta charset=utf-8>
<title>RTCPeerConnection Simulcast Tests - negotiation/encodings</title>
<meta name="timeout" content="long">
<script src="../third_party/sdp/sdp.js"></script>
<script src="simulcast.js"></script>
<script src="../RTCPeerConnection-helper.js"></script>
<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="../../mediacapture-streams/permission-helper.js"></script>
<script>
promise_test(async t => {
const pc1 = new RTCPeerConnection();
t.add_cleanup(() => pc1.close());
const pc2 = new RTCPeerConnection();
t.add_cleanup(() => pc2.close());
const stream = await getNoiseStream({video: true});
t.add_cleanup(() => stream.getTracks().forEach(track => track.stop()));
const sender = pc1.addTrack(stream.getTracks()[0]);
// pc1 is unicast right now
pc2.addTrack(stream.getTracks()[0]);
await doOfferToRecvSimulcastAndAnswer(pc2, pc1, ["foo", "bar"]);
assert_equals(pc1.getTransceivers().length, 1);
const {encodings} = sender.getParameters();
const rids = encodings.map(({rid}) => rid);
assert_array_equals(rids, ["foo", "bar"]);
}, 'addTrack, then sRD(simulcast recv offer) results in simulcast');
promise_test(async t => {
const pc1 = new RTCPeerConnection();
t.add_cleanup(() => pc1.close());
const pc2 = new RTCPeerConnection();
t.add_cleanup(() => pc2.close());
const stream = await getNoiseStream({audio: true});
t.add_cleanup(() => stream.getTracks().forEach(track => track.stop()));
const sender = pc1.addTrack(stream.getTracks()[0]);
// pc1 is unicast right now
pc2.addTrack(stream.getTracks()[0]);
await doOfferToRecvSimulcastAndAnswer(pc2, pc1, ["foo", "bar"]);
assert_equals(pc1.getTransceivers().length, 1);
const {encodings} = sender.getParameters();
const rids = encodings.map(({rid}) => rid);
assert_array_equals(rids, [undefined]);
}, 'simulcast is not supported for audio');
// We do not have a test case for sRD(offer) narrowing a simulcast envelope
// from addTransceiver, since that transceiver cannot be paired up with a remote
// offer m-section
promise_test(async t => {
const pc1 = new RTCPeerConnection();
t.add_cleanup(() => pc1.close());
const pc2 = new RTCPeerConnection();
t.add_cleanup(() => pc2.close());
const {sender} = pc1.addTransceiver("video", {sendEncodings: [{rid: "foo"}, {rid: "bar"}]});
let {encodings} = sender.getParameters();
await doOfferToSendSimulcastAndAnswer(pc1, pc2, ["foo"]);
assert_equals(pc1.getTransceivers().length, 1);
encodings = sender.getParameters().encodings;
const rids = encodings.map(({rid}) => rid);
assert_array_equals(rids, ["foo"]);
const scaleDownByValues = encodings.map(({scaleResolutionDownBy}) => scaleResolutionDownBy);
assert_array_equals(scaleDownByValues, [2]);
}, 'sRD(recv simulcast answer) can narrow the simulcast envelope specified by addTransceiver');
promise_test(async t => {
const pc1 = new RTCPeerConnection();
t.add_cleanup(() => pc1.close());
const pc2 = new RTCPeerConnection();
t.add_cleanup(() => pc2.close());
const {sender} = pc1.addTransceiver("video", {sendEncodings: [{rid: "foo"}, {rid: "bar"}]});
let {encodings} = sender.getParameters();
await doOfferToSendSimulcastAndAnswer(pc1, pc2, ["foo", "bar"]);
assert_equals(pc1.getTransceivers().length, 1);
encodings = sender.getParameters().encodings;
let rids = encodings.map(({rid}) => rid);
assert_array_equals(rids, ["foo", "bar"]);
await doOfferToSendSimulcastAndAnswer(pc1, pc2, ["foo"]);
assert_equals(pc1.getTransceivers().length, 1);
encodings = sender.getParameters().encodings;
rids = encodings.map(({rid}) => rid);
assert_array_equals(rids, ["foo"]);
const scaleDownByValues = encodings.map(({scaleResolutionDownBy}) => scaleResolutionDownBy);
assert_array_equals(scaleDownByValues, [2]);
}, 'sRD(recv simulcast answer) can narrow the simulcast envelope from a previous negotiation');
promise_test(async t => {
const pc1 = new RTCPeerConnection();
t.add_cleanup(() => pc1.close());
const pc2 = new RTCPeerConnection();
t.add_cleanup(() => pc2.close());
const {sender} = pc1.addTransceiver("video", {sendEncodings: [{rid: "foo"}, {rid: "bar"}]});
let {encodings} = sender.getParameters();
await doOfferToSendSimulcastAndAnswer(pc1, pc2, ["foo", "bar"]);
assert_equals(pc1.getTransceivers().length, 1);
encodings = sender.getParameters().encodings;
let rids = encodings.map(({rid}) => rid);
assert_array_equals(rids, ["foo", "bar"]);
// doAnswerToSendSimulcast causes pc2 to barf unless we set the direction to
// sendrecv
pc2.getTransceivers()[0].direction = "sendrecv";
pc2.getTransceivers()[1].direction = "sendrecv";
await doOfferToRecvSimulcast(pc2, pc1, ["foo"]);
assert_equals(pc1.getTransceivers().length, 1);
encodings = sender.getParameters().encodings;
rids = encodings.map(({rid}) => rid);
assert_array_equals(rids, ["foo", "bar"], "[[SendEncodings]] is not updated in have-remote-offer for reoffers");
await doAnswerToSendSimulcast(pc2, pc1);
assert_equals(pc1.getTransceivers().length, 1);
encodings = sender.getParameters().encodings;
rids = encodings.map(({rid}) => rid);
assert_array_equals(rids, ["foo"]);
const scaleDownByValues = encodings.map(({scaleResolutionDownBy}) => scaleResolutionDownBy);
assert_array_equals(scaleDownByValues, [2]);
}, 'sRD(simulcast offer) can narrow the simulcast envelope from a previous negotiation');
promise_test(async t => {
const pc1 = new RTCPeerConnection();
t.add_cleanup(() => pc1.close());
const pc2 = new RTCPeerConnection();
t.add_cleanup(() => pc2.close());
const stream = await getNoiseStream({video: true});
t.add_cleanup(() => stream.getTracks().forEach(track => track.stop()));
const sender = pc1.addTrack(stream.getTracks()[0]);
pc2.addTrack(stream.getTracks()[0]);
await doOfferToRecvSimulcastAndAnswer(pc2, pc1, ["foo", "bar", "foo"]);
assert_equals(pc1.getTransceivers().length, 1);
let {encodings} = sender.getParameters();
let rids = encodings.map(({rid}) => rid);
assert_array_equals(rids, ["foo", "bar"]);
assert_true(pc1.remoteDescription.sdp.includes("a=simulcast:recv foo;bar;foo"), "Duplicate rids should be present in offer");
assert_false(pc1.localDescription.sdp.includes("a=simulcast:send foo;bar;foo"), "Duplicate rids should not be present in answer");
assert_true(pc1.localDescription.sdp.includes("a=simulcast:send foo;bar"), "Answer should use the correct rids");
assert_equals(pc1.getTransceivers().length, 1);
encodings = sender.getParameters().encodings;
rids = encodings.map(({rid}) => rid);
assert_array_equals(rids, ["foo", "bar"]);
}, 'Duplicate rids in sRD(offer) are ignored');
promise_test(async t => {
const pc1 = new RTCPeerConnection();
t.add_cleanup(() => pc1.close());
const pc2 = new RTCPeerConnection();
t.add_cleanup(() => pc2.close());
const stream = await getNoiseStream({video: true});
t.add_cleanup(() => stream.getTracks().forEach(track => track.stop()));
const sender = pc1.addTrack(stream.getTracks()[0]);
pc2.addTrack(stream.getTracks()[0]);
await doOfferToRecvSimulcastAndAnswer(pc2, pc1, ["foo,bar", "1,2"]);
assert_equals(pc1.getTransceivers().length, 1);
let {encodings} = sender.getParameters();
let rids = encodings.map(({rid}) => rid);
assert_array_equals(rids, ["foo", "1"]);
assert_true(pc1.remoteDescription.sdp.includes("a=simulcast:recv foo,bar;1,2"), "Choices of rids should be present in offer");
assert_true(pc1.localDescription.sdp.includes("a=simulcast:send foo;1\r\n"), "Choices of rids should not be present in answer");
assert_equals(pc1.getTransceivers().length, 1);
encodings = sender.getParameters().encodings;
rids = encodings.map(({rid}) => rid);
assert_array_equals(rids, ["foo", "1"]);
}, 'Choices in rids in sRD(offer) are ignored');
promise_test(async t => {
const pc1 = new RTCPeerConnection();
t.add_cleanup(() => pc1.close());
const pc2 = new RTCPeerConnection();
t.add_cleanup(() => pc2.close());
const stream = await getNoiseStream({video: true});
t.add_cleanup(() => stream.getTracks().forEach(track => track.stop()));
const sender = pc1.addTrack(stream.getTracks()[0]);
pc2.addTrack(stream.getTracks()[0]);
await doOfferToRecvSimulcast(pc2, pc1, ["foo", "bar"]);
assert_equals(pc1.getTransceivers().length, 1);
let {encodings} = sender.getParameters();
let rids = encodings.map(({rid}) => rid);
assert_array_equals(rids, ["foo", "bar"]);
await pc1.setRemoteDescription({sdp: "", type: "rollback"});
assert_equals(pc1.getTransceivers().length, 1);
encodings = sender.getParameters().encodings;
rids = encodings.map(({rid}) => rid);
assert_array_equals(rids, [undefined]);
}, 'addTrack, then rollback of sRD(simulcast offer), brings us back to having a single encoding without a rid');
promise_test(async t => {
const pc1 = new RTCPeerConnection();
t.add_cleanup(() => pc1.close());
const pc2 = new RTCPeerConnection();
t.add_cleanup(() => pc2.close());
const stream = await getNoiseStream({video: true});
t.add_cleanup(() => stream.getTracks().forEach(track => track.stop()));
pc2.addTrack(stream.getTracks()[0]);
await doOfferToRecvSimulcast(pc2, pc1, ["foo", "bar"]);
const sender = pc1.addTrack(stream.getTracks()[0]);
assert_equals(pc1.getTransceivers().length, 1);
assert_equals(pc1.getTransceivers().length, 1);
let {encodings} = sender.getParameters();
let rids = encodings.map(({rid}) => rid);
assert_array_equals(rids, ["foo", "bar"]);
await pc1.setRemoteDescription({sdp: "", type: "rollback"});
assert_equals(pc1.getTransceivers().length, 1);
encodings = sender.getParameters().encodings;
rids = encodings.map(({rid}) => rid);
assert_array_equals(rids, [undefined]);
}, 'sRD(simulcast offer), addTrack, then rollback brings us back to having a single encoding');
promise_test(async t => {
const pc1 = new RTCPeerConnection();
t.add_cleanup(() => pc1.close());
const pc2 = new RTCPeerConnection();
t.add_cleanup(() => pc2.close());
const stream = await getNoiseStream({video: true});
t.add_cleanup(() => stream.getTracks().forEach(track => track.stop()));
const {sender} = pc1.addTransceiver(stream.getTracks()[0], {sendEncodings: [{rid: "foo"}, {rid: "bar"}]});
await doOfferToSendSimulcast(pc1, pc2);
await doAnswerToRecvSimulcast(pc1, pc2, ["bar", "foo"]);
assert_true(pc1.remoteDescription.sdp.includes("a=simulcast:recv bar;foo"), "Answer should have reordered rids");
assert_equals(pc1.getTransceivers().length, 1);
const {encodings} = sender.getParameters();
const rids = encodings.map(({rid}) => rid);
assert_array_equals(rids, ["foo", "bar"]);
}, 'Reordering of rids in sRD(answer) is ignored');
promise_test(async t => {
const pc1 = new RTCPeerConnection();
t.add_cleanup(() => pc1.close());
const pc2 = new RTCPeerConnection();
t.add_cleanup(() => pc2.close());
const stream = await getNoiseStream({video: true});
t.add_cleanup(() => stream.getTracks().forEach(track => track.stop()));
const {sender} = pc1.addTransceiver(stream.getTracks()[0], {sendEncodings: [{rid: "foo"}, {rid: "bar"}]});
await doOfferToSendSimulcastAndAnswer(pc1, pc2, ["foo", "bar"]);
assert_equals(pc1.getTransceivers().length, 1);
let {encodings} = sender.getParameters();
let rids = encodings.map(({rid}) => rid);
assert_array_equals(rids, ["foo", "bar"]);
await doOfferToSendSimulcast(pc1, pc2);
await doAnswerToRecvSimulcast(pc1, pc2, ["bar", "foo"]);
assert_true(pc1.remoteDescription.sdp.includes("a=simulcast:recv bar;foo"), "Answer should have reordered rids");
assert_equals(pc1.getTransceivers().length, 1);
encodings = sender.getParameters().encodings;
rids = encodings.map(({rid}) => rid);
assert_array_equals(rids, ["foo", "bar"]);
}, 'Reordering of rids in sRD(reanswer) is ignored');
promise_test(async t => {
const pc1 = new RTCPeerConnection();
t.add_cleanup(() => pc1.close());
const pc2 = new RTCPeerConnection();
t.add_cleanup(() => pc2.close());
const stream = await getNoiseStream({video: true});
t.add_cleanup(() => stream.getTracks().forEach(track => track.stop()));
const {sender} = pc1.addTransceiver(stream.getTracks()[0], {sendEncodings: [{rid: "foo"}, {rid: "bar"}]});
await doOfferToSendSimulcastAndAnswer(pc1, pc2, ["foo", "bar"]);
assert_equals(pc1.getTransceivers().length, 1);
let {encodings} = sender.getParameters();
let rids = encodings.map(({rid}) => rid);
assert_array_equals(rids, ["foo", "bar"]);
// doAnswerToSendSimulcast causes pc2 to barf unless we set the direction to
// sendrecv
pc2.getTransceivers()[0].direction = "sendrecv";
pc2.getTransceivers()[1].direction = "sendrecv";
await doOfferToRecvSimulcast(pc2, pc1, ["bar", "foo"]);
await doAnswerToSendSimulcast(pc2, pc1);
assert_true(pc1.remoteDescription.sdp.includes("a=simulcast:recv bar;foo"), "Reoffer should have reordered rids");
assert_equals(pc1.getTransceivers().length, 1);
encodings = sender.getParameters().encodings;
rids = encodings.map(({rid}) => rid);
assert_array_equals(rids, ["foo", "bar"]);
}, 'Reordering of rids in sRD(reoffer) is ignored');
promise_test(async t => {
const pc1 = new RTCPeerConnection();
t.add_cleanup(() => pc1.close());
const pc2 = new RTCPeerConnection();
t.add_cleanup(() => pc2.close());
const stream = await getNoiseStream({video: true});
t.add_cleanup(() => stream.getTracks().forEach(track => track.stop()));
const {sender} = pc1.addTransceiver(stream.getTracks()[0], {sendEncodings: [{rid: "foo"}, {rid: "bar"}]});
await doOfferToSendSimulcastAndAnswer(pc1, pc2, ["foo", "bar"]);
assert_equals(pc1.getTransceivers().length, 1);
let encodings = sender.getParameters().encodings;
let rids = encodings.map(({rid}) => rid);
assert_array_equals(rids, ["foo", "bar"]);
// doAnswerToSendSimulcast causes pc2 to barf unless we set the direction to
// sendrecv
pc2.getTransceivers()[0].direction = "sendrecv";
pc2.getTransceivers()[1].direction = "sendrecv";
// Keep the second encoding!
await doOfferToRecvSimulcast(pc2, pc1, ["bar"]);
assert_equals(pc1.getTransceivers().length, 1);
encodings = sender.getParameters().encodings;
rids = encodings.map(({rid}) => rid);
assert_array_equals(rids, ["foo", "bar"]);
await pc1.setRemoteDescription({sdp: "", type: "rollback"});
encodings = sender.getParameters().encodings;
rids = encodings.map(({rid}) => rid);
assert_array_equals(rids, ["foo", "bar"]);
}, 'Rollback of sRD(reoffer) with a single rid results in all previous encodings');
promise_test(async t => {
const pc1 = new RTCPeerConnection();
t.add_cleanup(() => pc1.close());
const pc2 = new RTCPeerConnection();
t.add_cleanup(() => pc2.close());
const {sender} = pc1.addTransceiver("video", {sendEncodings: [{rid: "foo"}, {rid: "bar"}]});
let {encodings} = sender.getParameters();
await doOfferToSendSimulcastAndAnswer(pc1, pc2, ["bar"]);
assert_equals(pc1.getTransceivers().length, 1);
encodings = sender.getParameters().encodings;
const rids = encodings.map(({rid}) => rid);
assert_array_equals(rids, ["bar"]);
const scaleDownByValues = encodings.map(({scaleResolutionDownBy}) => scaleResolutionDownBy);
assert_array_equals(scaleDownByValues, [1]);
}, 'sRD(recv simulcast answer) can narrow the simulcast envelope specified by addTransceiver by removing the first encoding');
promise_test(async t => {
const pc1 = new RTCPeerConnection();
t.add_cleanup(() => pc1.close());
const pc2 = new RTCPeerConnection();
t.add_cleanup(() => pc2.close());
const {sender} = pc1.addTransceiver("video", {sendEncodings: [{rid: "foo"}, {rid: "bar"}]});
let {encodings} = sender.getParameters();
await doOfferToSendSimulcastAndAnswer(pc1, pc2, ["foo", "bar"]);
assert_equals(pc1.getTransceivers().length, 1);
encodings = sender.getParameters().encodings;
let rids = encodings.map(({rid}) => rid);
assert_array_equals(rids, ["foo", "bar"]);
await doOfferToSendSimulcastAndAnswer(pc1, pc2, ["bar"]);
assert_equals(pc1.getTransceivers().length, 1);
encodings = sender.getParameters().encodings;
rids = encodings.map(({rid}) => rid);
assert_array_equals(rids, ["bar"]);
const scaleDownByValues = encodings.map(({scaleResolutionDownBy}) => scaleResolutionDownBy);
assert_array_equals(scaleDownByValues, [1]);
}, 'sRD(recv simulcast answer) can narrow the simulcast envelope from a previous negotiation by removing the first encoding');
promise_test(async t => {
const pc1 = new RTCPeerConnection();
t.add_cleanup(() => pc1.close());
const pc2 = new RTCPeerConnection();
t.add_cleanup(() => pc2.close());
const {sender} = pc1.addTransceiver("video", {sendEncodings: [{rid: "foo"}, {rid: "bar"}]});
let {encodings} = sender.getParameters();
await doOfferToSendSimulcastAndAnswer(pc1, pc2, ["foo", "bar"]);
assert_equals(pc1.getTransceivers().length, 1);
encodings = sender.getParameters().encodings;
let rids = encodings.map(({rid}) => rid);
assert_array_equals(rids, ["foo", "bar"]);
// doAnswerToSendSimulcast causes pc2 to barf unless we set the direction to
// sendrecv
pc2.getTransceivers()[0].direction = "sendrecv";
pc2.getTransceivers()[1].direction = "sendrecv";
await doOfferToRecvSimulcast(pc2, pc1, ["bar"]);
assert_equals(pc1.getTransceivers().length, 1);
encodings = sender.getParameters().encodings;
rids = encodings.map(({rid}) => rid);
assert_array_equals(rids, ["foo", "bar"], "[[SendEncodings]] is not updated in have-remote-offer for reoffers");
await doAnswerToSendSimulcast(pc2, pc1);
assert_equals(pc1.getTransceivers().length, 1);
encodings = sender.getParameters().encodings;
rids = encodings.map(({rid}) => rid);
assert_array_equals(rids, ["bar"]);
const scaleDownByValues = encodings.map(({scaleResolutionDownBy}) => scaleResolutionDownBy);
assert_array_equals(scaleDownByValues, [1]);
}, 'sRD(simulcast offer) can narrow the simulcast envelope from a previous negotiation by removing the first encoding');
promise_test(async t => {
const pc1 = new RTCPeerConnection();
t.add_cleanup(() => pc1.close());
const pc2 = new RTCPeerConnection();
t.add_cleanup(() => pc2.close());
const {sender} = pc1.addTransceiver("video", {sendEncodings: [{rid: "foo"}, {rid: "bar"}]});
let {encodings} = sender.getParameters();
await doOfferToSendSimulcastAndAnswer(pc1, pc2, ["foo", "bar"]);
assert_equals(pc1.getTransceivers().length, 1);
encodings = sender.getParameters().encodings;
let rids = encodings.map(({rid}) => rid);
assert_array_equals(rids, ["foo", "bar"]);
pc1.getTransceivers()[0].direction = "inactive";
await doOfferToSendSimulcastAndAnswer(pc1, pc2, ["foo", "bar"]);
assert_equals(pc1.getTransceivers().length, 1);
encodings = sender.getParameters().encodings;
rids = encodings.map(({rid}) => rid);
assert_array_equals(rids, ["foo", "bar"]);
}, 'sender renegotiation to inactive does not disable simulcast');
promise_test(async t => {
const pc1 = new RTCPeerConnection();
t.add_cleanup(() => pc1.close());
const pc2 = new RTCPeerConnection();
t.add_cleanup(() => pc2.close());
const {sender} = pc1.addTransceiver("video", {sendEncodings: [{rid: "foo"}, {rid: "bar"}]});
let {encodings} = sender.getParameters();
await doOfferToSendSimulcastAndAnswer(pc1, pc2, ["foo", "bar"]);
assert_equals(pc1.getTransceivers().length, 1);
encodings = sender.getParameters().encodings;
let rids = encodings.map(({rid}) => rid);
assert_array_equals(rids, ["foo", "bar"]);
pc1.getTransceivers()[0].direction = "recvonly";
await doOfferToSendSimulcastAndAnswer(pc1, pc2, ["foo", "bar"]);
assert_equals(pc1.getTransceivers().length, 1);
encodings = sender.getParameters().encodings;
rids = encodings.map(({rid}) => rid);
assert_array_equals(rids, ["foo", "bar"]);
}, 'sender renegotiation to recvonly does not disable simulcast');
promise_test(async t => {
const pc1 = new RTCPeerConnection();
t.add_cleanup(() => pc1.close());
const pc2 = new RTCPeerConnection();
t.add_cleanup(() => pc2.close());
const {sender} = pc1.addTransceiver("video", {sendEncodings: [{rid: "foo"}, {rid: "bar"}]});
let {encodings} = sender.getParameters();
await doOfferToSendSimulcastAndAnswer(pc1, pc2, ["foo", "bar"]);
assert_equals(pc1.getTransceivers().length, 1);
encodings = sender.getParameters().encodings;
let rids = encodings.map(({rid}) => rid);
assert_array_equals(rids, ["foo", "bar"]);
pc2.getTransceivers()[0].direction = "inactive";
pc2.getTransceivers()[1].direction = "inactive";
await doOfferToSendSimulcastAndAnswer(pc1, pc2, ["foo", "bar"]);
assert_equals(pc1.getTransceivers().length, 1);
encodings = sender.getParameters().encodings;
rids = encodings.map(({rid}) => rid);
assert_array_equals(rids, ["foo", "bar"]);
}, 'receiver renegotiation to inactive does not disable simulcast');
promise_test(async t => {
const pc1 = new RTCPeerConnection();
t.add_cleanup(() => pc1.close());
const pc2 = new RTCPeerConnection();
t.add_cleanup(() => pc2.close());
const {sender} = pc1.addTransceiver("video", {sendEncodings: [{rid: "foo"}, {rid: "bar"}]});
let {encodings} = sender.getParameters();
await doOfferToSendSimulcastAndAnswer(pc1, pc2, ["foo", "bar"]);
assert_equals(pc1.getTransceivers().length, 1);
encodings = sender.getParameters().encodings;
let rids = encodings.map(({rid}) => rid);
assert_array_equals(rids, ["foo", "bar"]);
pc2.getTransceivers()[0].direction = "sendonly";
pc2.getTransceivers()[1].direction = "sendonly";
await doOfferToSendSimulcastAndAnswer(pc1, pc2, ["foo", "bar"]);
assert_equals(pc1.getTransceivers().length, 1);
encodings = sender.getParameters().encodings;
rids = encodings.map(({rid}) => rid);
assert_array_equals(rids, ["foo", "bar"]);
}, 'receiver renegotiation to sendonly does not disable simulcast');
</script>