fix(jasminewd): allow asynchronous callbacks for jasmine tests

Closes #728, Closes #704

Author: hankduan

jasminewd/index.js

@@ -80,12 +80,25 @@ function wrapInControlFlow(globalFn, fnName) {
         }
         desc_ += ')';
 
+        // deferred object for signaling completion of asychronous function within globalFn
+        var asyncFnDone = webdriver.promise.defer();
+
+        if (fn.length == 0) {
+          // function with globalFn not asychronous
+          asyncFnDone.fulfill();
+        } else if (fn.length > 1) {
+          throw Error('Invalid # arguments (' + fn.length + ') within function "' + fnName +'"');
+        }
+
         flow.execute(function() {
-          fn.call(jasmine.getEnv().currentSpec, function() {
-            throw new Error('Do not use a done callback with WebDriverJS tests. ' +
-                'The tests are patched to be asynchronous and will terminate when ' +
-                'the webdriver control flow is empty.');
+          fn.call(jasmine.getEnv().currentSpec, function(userError) {
+            if (userError) {
+              asyncFnDone.reject(new Error(userError));
+            } else {
+              asyncFnDone.fulfill();
+            }
           });
+          return asyncFnDone.promise;
         }, desc_).then(seal(done), function(e) {
           e.stack = e.stack + '==== async task ====\n' + driverError.stack;
           done(e);

jasminewd/spec/adapterSpec.js

@@ -186,11 +186,34 @@ describe('webdriverJS Jasmine adapter', function() {
   //   expect(fakeDriver.getValueB()).toEqual('b');
   // }, 300);
 
-  // it('should error with a warning if done callback is used', function(done) {
-  //   done();
+  // it('should pass errors from done callback', function(done) {
+  //   done('an error');
   // });
 
   it('should pass after the timed out tests', function() {
     expect(true).toEqual(true);
   });
+
+  describe('should work for both synchronous and asynchronous tests', function() {
+    var x;
+
+    beforeEach(function() {
+      x = 0;
+    });
+
+    afterEach(function() {
+      expect(x).toBe(1);
+    });
+
+    it('should execute a synchronous test', function() {
+      x = 1;
+    });
+
+    it('should execute an asynchronous test', function(done) {
+      setTimeout(function(){
+        x = 1;
+        done();
+      }, 500);
+    });
+  });
 });