Provide better error for ICE Server SyntaxError (#3694)

* Provide better error for ICE Server SyntaxError

* Refactor

* Add test

spec/unit/webrtc/call.spec.ts

@@ -47,6 +47,7 @@ import {
 } from "../../test-utils/webrtc";
 import { CallFeed } from "../../../src/webrtc/callFeed";
 import { EventType, IContent, ISendEventResponse, MatrixEvent, Room } from "../../../src";
+import { emitPromise } from "../../test-utils/test-utils";
 
 const FAKE_ROOM_ID = "!foo:bar";
 const CALL_LIFETIME = 60000;
@@ -1812,4 +1813,30 @@ describe("Call", function () {
             expect(call.peerConn?.setRemoteDescription).toHaveBeenCalled();
         });
     });
+
+    it("should emit IceFailed error on the successor call if RTCPeerConnection throws", async () => {
+        // @ts-ignore - writing to window as we are simulating browser edge-cases
+        global.window = {};
+        Object.defineProperty(global.window, "RTCPeerConnection", {
+            get: () => {
+                throw Error("Secure mode, naaah!");
+            },
+        });
+
+        const call = new MatrixCall({
+            client: client.client,
+            roomId: "!room_id",
+        });
+        const successor = new MatrixCall({
+            client: client.client,
+            roomId: "!room_id",
+        });
+        call.replacedBy(successor);
+
+        const prom = emitPromise(successor, CallEvent.Error);
+        call.placeCall(true, true);
+
+        const err = await prom;
+        expect(err.code).toBe(CallErrorCode.IceFailed);
+    });
 });

src/webrtc/call.ts

@@ -2220,7 +2220,7 @@ export class MatrixCall extends TypedEventEmitter<CallEvent, CallEventHandlerMap
             CallEvent.Error,
             new CallError(
                 CallErrorCode.NoUserMedia,
-                "Couldn't start capturing media! Is your microphone set up and " + "does this app have permission?",
+                "Couldn't start capturing media! Is your microphone set up and does this app have permission?",
                 err,
             ),
             this,
@@ -2228,6 +2228,22 @@ export class MatrixCall extends TypedEventEmitter<CallEvent, CallEventHandlerMap
         this.terminate(CallParty.Local, CallErrorCode.NoUserMedia, false);
     };
 
+    private placeCallFailed = (err: Error): void => {
+        if (this.successor) {
+            this.successor.placeCallFailed(err);
+            return;
+        }
+
+        logger.warn(`Call ${this.callId} placeCallWithCallFeeds() failed - ending call`, err);
+
+        this.emit(
+            CallEvent.Error,
+            new CallError(CallErrorCode.IceFailed, "Couldn't start call! Invalid ICE server configuration.", err),
+            this,
+        );
+        this.terminate(CallParty.Local, CallErrorCode.IceFailed, false);
+    };
+
     private onIceConnectionStateChanged = (): void => {
         if (this.callHasEnded()) {
             return; // because ICE can still complete as we're ending the call
@@ -2775,6 +2791,7 @@ export class MatrixCall extends TypedEventEmitter<CallEvent, CallEventHandlerMap
         }
         this.state = CallState.WaitLocalMedia;
 
+        let callFeed: CallFeed;
         try {
             const stream = await this.client.getMediaHandler().getUserMediaStream(audio, video);
 
@@ -2783,7 +2800,7 @@ export class MatrixCall extends TypedEventEmitter<CallEvent, CallEventHandlerMap
             setTracksEnabled(stream.getAudioTracks(), true);
             setTracksEnabled(stream.getVideoTracks(), true);
 
-            const callFeed = new CallFeed({
+            callFeed = new CallFeed({
                 client: this.client,
                 roomId: this.roomId,
                 userId: this.client.getUserId()!,
@@ -2793,11 +2810,17 @@ export class MatrixCall extends TypedEventEmitter<CallEvent, CallEventHandlerMap
                 audioMuted: false,
                 videoMuted: false,
             });
-            await this.placeCallWithCallFeeds([callFeed]);
         } catch (e) {
             this.getUserMediaFailed(<Error>e);
             return;
         }
+
+        try {
+            await this.placeCallWithCallFeeds([callFeed]);
+        } catch (e) {
+            this.placeCallFailed(<Error>e);
+            return;
+        }
     }
 
     /**