1 files changed, 50 insertions, 0 deletions
diff --git a/testing/web-platform/tests/webrtc-svc/svc-helper.js b/testing/web-platform/tests/webrtc-svc/svc-helper.js
new file mode 100644
index 0000000000..e73ccfa750
--- /dev/null
+++ b/testing/web-platform/tests/webrtc-svc/svc-helper.js
@@ -0,0 +1,50 @@
+function supportsCodec(mimeType) {
+  return RTCRtpSender.getCapabilities('video').codecs.filter(c => c.mimeType == mimeType).length() > 0;
+}
+
+async function supportsScalabilityMode(mimeType, scalabilityMode) {
+  let result = await navigator.mediaCapabilities.encodingInfo({
+    type: 'webrtc',
+    video: {
+      contentType: mimeType,
+      width: 60,
+      height: 60,
+      bitrate: 10000,
+      framerate: 30,
+      scalabilityMode: scalabilityMode
+    }
+  });
+  return result.supported;
+}
+
+function createScalabilityTest(mimeType, scalabilityModes) {
+  for (const scalabilityMode of scalabilityModes) {
+    promise_test(async t => {
+      assert_implements_optional(
+        supportsScalabilityMode(mimeType, scalabilityMode),
+        `${mimeType} supported`
+      );
+      const v = document.createElement('video');
+      v.autoplay = true;
+      const pc1 = new RTCPeerConnection();
+      const pc2 = new RTCPeerConnection();
+      t.add_cleanup(() => pc1.close());
+      t.add_cleanup(() => pc2.close());
+      const stream1 = await getNoiseStream({ video: { signal: 100, width: 60, height: 60 } });
+      const [track1] = stream1.getTracks();
+      t.add_cleanup(() => track1.stop());
+      const transceiver = pc1.addTransceiver(track1, {
+        sendEncodings: [{ scalabilityMode: scalabilityMode }],
+      });
+      transceiver.setCodecPreferences(RTCRtpSender.getCapabilities('video').codecs.filter(c => c.mimeType == mimeType));
+      const haveTrackEvent = new Promise(r => pc2.ontrack = r);
+      exchangeIceCandidates(pc1, pc2);
+      await exchangeOfferAnswer(pc1, pc2);
+      v.srcObject = new MediaStream([(await haveTrackEvent).track]);
+      await new Promise(r => v.onloadedmetadata = r);
+      await detectSignal(t, v, 100);
+      const sendParams = pc1.getSenders()[0].getParameters();
+      assert_equals(sendParams.encodings[0].scalabilityMode, scalabilityMode);
+    }, `${mimeType} - ${scalabilityMode} should produce valid video content`);
+  }
+}