Throw error on unsupported broadcaster (#396)

* Throw error on unsupported broadcaster

* update CS

* fix CS

* fix cs

* fix eslint

* Removed return

* fix CS

* Update echo.ts

* Update echo.test.ts

---------

Co-authored-by: Taylor Otwell <taylor@laravel.com>

src/echo.ts

@@ -48,6 +48,10 @@ export default class Echo {
             this.connector = new NullConnector(this.options);
         } else if (typeof this.options.broadcaster == 'function') {
             this.connector = new this.options.broadcaster(this.options);
+        } else {
+            throw new Error(
+                `Broadcaster ${typeof this.options.broadcaster} ${this.options.broadcaster} is not supported.`
+            );
         }
     }
 

tests/echo.test.ts

@@ -0,0 +1,26 @@
+import Echo from '../src/echo';
+
+describe('Echo', () => {
+    test('it will not throw error for supported driver', () => {
+        expect(() => new Echo({ broadcaster: 'reverb' })).not.toThrowError(
+            'Broadcaster string reverb is not supported.'
+        );
+
+        expect(() => new Echo({ broadcaster: 'pusher' })).not.toThrowError(
+            'Broadcaster string pusher is not supported.'
+        );
+
+        expect(() => new Echo({ broadcaster: 'socket.io' })).not.toThrowError(
+            'Broadcaster string socket.io is not supported.'
+        );
+
+        expect(() => new Echo({ broadcaster: 'null' })).not.toThrowError('Broadcaster string null is not supported.');
+
+        // eslint-disable-next-line @typescript-eslint/no-empty-function
+        expect(() => new Echo({ broadcaster: () => {} })).not.toThrowError('Broadcaster function is not supported.');
+    });
+
+    test('it will throw error for unsupported driver', () => {
+        expect(() => new Echo({ broadcaster: 'foo' })).toThrowError('Broadcaster string foo is not supported.');
+    });
+});