Fix compatibility check when mediaDevices is unavailable

src/utilities/HiFiUtilities.ts

@@ -195,21 +195,21 @@ export class HiFiUtilities {
     }
 
     static checkBrowserCompatibility(): Boolean {
-        let requiredFeatures: Array<string> = [
+        let requiredFeatures: Array<{ name: string, value: () => any }> = [
             // Navigator mediaDevices
-            "navigator", // Found on source code HiFiMixerSession.ts, RaviStreamController.ts
-            "navigator.mediaDevices.getUserMedia", // Found on source code HiFiMixerSession.ts (ln.590)
-            "navigator.mediaDevices.getSupportedConstraints", // Found on source code HiFiUtilities (ln. 130, 134, 138)
+            { name: "navigator", value: () => typeof navigator !== "undefined" ? navigator : undefined }, // Found on source code HiFiMixerSession.ts, RaviStreamController.ts
+            { name: "navigator.mediaDevices.getUserMedia", value: () => typeof navigator !== "undefined" && navigator.mediaDevices ? navigator.mediaDevices.getUserMedia : undefined }, // Found on source code HiFiMixerSession.ts (ln.590)
+            { name: "navigator.mediaDevices.getSupportedConstraints", value: () => typeof navigator !== "undefined" && navigator.mediaDevices ? navigator.mediaDevices.getSupportedConstraints : undefined }, // Found on source code HiFiUtilities (ln. 130, 134, 138)
             // WebRTC
-            "window.MediaStream", // Found on source code HiFiCommunicator.ts, HiFiMixerSession.ts, RaviSession.ts, RaviStreamController.ts
-            "window.RTCDataChannel", // Found on source code RaviCommandController.ts (ln.151)
-            "window.RTCPeerConnection", // Found on source code RaviSession.ts (ln.603)
-            "window.RTCSessionDescription" // Found on source code RaviSession.ts (ln.604)
+            { name: "window.MediaStream", value: () => typeof window !== "undefined" ? window.MediaStream : undefined }, // Found on source code HiFiCommunicator.ts, HiFiMixerSession.ts, RaviSession.ts, RaviStreamController.ts
+            { name: "window.RTCDataChannel", value: () => typeof window !== "undefined" ? window.RTCDataChannel : undefined }, // Found on source code RaviCommandController.ts (ln.151)
+            { name: "window.RTCPeerConnection", value: () => typeof window !== "undefined" ? window.RTCPeerConnection : undefined }, // Found on source code RaviSession.ts (ln.603)
+            { name: "window.RTCSessionDescription", value: () => typeof window !== "undefined" ? window.RTCSessionDescription : undefined } // Found on source code RaviSession.ts (ln.604)
         ]
         for (let i = 0; i < requiredFeatures.length; i++) {
-            if (typeof (eval(requiredFeatures[i])) === "undefined") {
-                HiFiLogger.error("HiFi Audio API: The browser does not support: " + requiredFeatures[i]);
-                if (requiredFeatures[i] === "navigator.mediaDevices.getUserMedia") {
+            if (typeof (requiredFeatures[i].value()) === "undefined") {
+                HiFiLogger.error("HiFi Audio API: The browser does not support: " + requiredFeatures[i].name);
+                if (requiredFeatures[i].name === "navigator.mediaDevices.getUserMedia") {
                     HiFiLogger.error("HiFi Audio API: Your browser may be preventing access to this feature if you are running in an insecure context, i.e. an `http` server.");
                 }
                 return false;

tests/unit/src/utilities/HiFiUtilities.unit.test.ts

@@ -0,0 +1,62 @@
+import { HiFiUtilities } from "../../../../src/utilities/HiFiUtilities";
+
+describe("checkBrowserCompatibility", () => {
+    let navigatorDescriptor: PropertyDescriptor | undefined;
+    let windowDescriptor: PropertyDescriptor | undefined;
+
+    beforeEach(() => {
+        navigatorDescriptor = Object.getOwnPropertyDescriptor(global, "navigator");
+        windowDescriptor = Object.getOwnPropertyDescriptor(global, "window");
+        jest.spyOn(console, "error").mockImplementation(() => {});
+    });
+
+    afterEach(() => {
+        jest.restoreAllMocks();
+
+        if (navigatorDescriptor) {
+            Object.defineProperty(global, "navigator", navigatorDescriptor);
+        } else {
+            delete (global as any).navigator;
+        }
+
+        if (windowDescriptor) {
+            Object.defineProperty(global, "window", windowDescriptor);
+        } else {
+            delete (global as any).window;
+        }
+    });
+
+    test("returns false instead of throwing when mediaDevices is unavailable", () => {
+        Object.defineProperty(global, "navigator", {
+            configurable: true,
+            value: {}
+        });
+
+        let compatibilityResult: Boolean | undefined;
+        expect(() => compatibilityResult = HiFiUtilities.checkBrowserCompatibility()).not.toThrow();
+        expect(compatibilityResult).toBe(false);
+    });
+
+    test("returns true when every required browser feature is available", () => {
+        Object.defineProperty(global, "navigator", {
+            configurable: true,
+            value: {
+                mediaDevices: {
+                    getUserMedia: (): any => undefined,
+                    getSupportedConstraints: () => ({})
+                }
+            }
+        });
+        Object.defineProperty(global, "window", {
+            configurable: true,
+            value: {
+                MediaStream: function () {},
+                RTCDataChannel: function () {},
+                RTCPeerConnection: function () {},
+                RTCSessionDescription: function () {}
+            }
+        });
+
+        expect(HiFiUtilities.checkBrowserCompatibility()).toBe(true);
+    });
+});