Add unit tests for passing WebSocket objects

tests/test.rfb.js

@@ -141,12 +141,14 @@ describe('Remote Frame Buffer Protocol Client', function () {
 
     describe('Connecting/Disconnecting', function () {
         describe('#RFB (constructor)', function () {
-            let open;
+            let open, attach;
             beforeEach(function () {
                 open = sinon.spy(Websock.prototype, 'open');
+                attach = sinon.spy(Websock.prototype, 'attach');
             });
             afterEach(function () {
                 open.restore();
+                attach.restore();
             });
 
             it('should not connect from constructor', function () {
@@ -160,6 +162,14 @@ describe('Remote Frame Buffer Protocol Client', function () {
                 this.clock.tick();
                 expect(open).to.have.been.calledOnceWithExactly('ws://HOST:8675/PATH', []);
             });
+
+            it('should handle WebSocket/RTCDataChannel objects', function () {
+                let sock = new FakeWebSocket('ws://HOST:8675/PATH', []);
+                new RFB(document.createElement('div'), sock);
+                this.clock.tick();
+                expect(open).to.not.have.been.called;
+                expect(attach).to.have.been.calledOnceWithExactly(sock);
+            });
         });
 
         describe('#disconnect', function () {

tests/test.websock.js

@@ -270,6 +270,27 @@ describe('Websock', function () {
             // it('should initialize the event handlers')?
         });
 
+        describe('attaching', function () {
+            it('should attach to an existing open websocket', function () {
+                let ws = new FakeWebSocket('ws://localhost:8675');
+                ws._open();
+                let callback = sinon.spy();
+                sock.on('open', callback);
+                sock.attach(ws);
+                expect(WebSocket).to.not.have.been.called;
+                expect(callback).to.have.been.calledOnce;
+            });
+
+            it('should attach to an existing connecting websocket', function () {
+                let ws = new FakeWebSocket('ws://localhost:8675');
+                let callback = sinon.spy();
+                sock.on('open', callback);
+                sock.attach(ws);
+                expect(WebSocket).to.not.have.been.called;
+                expect(callback).to.not.have.been.called;
+            });
+        });
+
         describe('closing', function () {
             beforeEach(function () {
                 sock.open('ws://localhost');