Added a test to verify that transports that fail to parse responses w…

…hile connecting indeed do fall back.

- Also fixed some long polling logic

#2506

src/Microsoft.AspNet.SignalR.Client.JS/jquery.signalR.transports.longPolling.js

@@ -47,14 +47,14 @@
             /// <summary>Starts the long polling connection</summary>
             /// <param name="connection" type="signalR">The SignalR connection to start</param>
             var that = this,
-                initialConnectedFired = false,
                 fireConnect = function () {
-                    if (initialConnectedFired) {
-                        return;
-                    }
-                    initialConnectedFired = true;
-                    onSuccess();
+                    tryFailConnect = fireConnect = $.noop;
+
                     connection.log("Longpolling connected.");
+                    onSuccess();
+
+                    // Reset onFailed to null because it shouldn't be called again
+                    onFailed = null;
                 },
                 tryFailConnect = function () {
                     if (onFailed) {

tests/Microsoft.AspNet.SignalR.Client.JS.Tests/Tests/FunctionalTests/Common/ResponseRedirectionFacts.js

@@ -10,6 +10,28 @@
 
 QUnit.module("Response redirection facts");
 
+QUnit.asyncTimeoutTest("Transport connect fails on response redirection causing negotiate to fallback through all transports.", testUtilities.defaultTestTimeout * 4000, function (end, assert, testName) {
+    var connection = buildRedirectConnection("connect", end, assert, testName, false);
+
+    connection.start().done(function () {
+        // Dont fail if we're long polling, just stop, this is primarily because there's no init message and there's a race to determine if the tranport connected successfully
+        if (connection.transport.name === "longPolling") {
+            end();
+        }
+
+        assert.fail("Connection was started successfully.");
+        end();
+    }).fail(function () {
+        assert.comment("Connection start deferred failure was triggered.");
+        end();
+    });
+
+    // Cleanup
+    return function () {
+        connection.stop();
+    };
+});
+
 testUtilities.runWithAllTransports(function (transport) {
     QUnit.asyncTimeoutTest(transport + ": Negotiate fails on response redirection.", testUtilities.defaultTestTimeout, function (end, assert, testName) {
         var connection = buildRedirectConnection("negotiate", end, assert, testName, false);