Edit in JSFiddle

        // Here is a simple function for opening a dialog box.
        // This is the "system under test" (SUT)
        function displayMessage(message, title) {

            // Setup the KendoWindow as a dialog box
            var dialog = $("#message").kendoWindow({
                width: "300px",
                height: "200px",
                title: title,
                modal: true,
                visible: false,
                actions: ["Close"]
            });

            // Inject the message argument into the window
            $("#message").html(message);

            // Center and open the window
            dialog.data("kendoWindow")
                  .center()
                  .open();
        }

        // Sample usage - setting up a button that will invoke the SUT
        $("#showMessage").click(function () {
            console.log("button clicked");
            displayMessage("here's the message", "and this is the title");
        });

        // A few variables that will help us setup the tests
        var sandbox; // this will be a SinonJS sandbox - a container for mocks, stubs, and spies.
        var kendoWindowSpy // this will be a spy for the KendoWindow;
        var jQueryHtmlSpy // and this will become a spy for changing the HTML inside the window;

        // Prepare a QUnit module for testing - this is the test fixture
        module("displayMessage tests",
            {
                setup: function () {
                    sandbox = sinon.sandbox.create();

                    // Using mocks with jQuery and Kendo is very challenging, since you have to
                    // specify all behavior and returned objects. Instead, SinonJS's spies functionality
                    // is the right choice - it allows us to look at what was called, without
                    // having specify all expected behavior. In .Net testing, I prefer mocks
                    // so that we can define all expected behavior. But so far I've simply
                    // found that to be impractical in Javascript tests.
                    jQueryHtmlSpy = sandbox.spy(jQuery.fn, "html");
                    kendoWindowSpy = sandbox.spy(jQuery.fn, "kendoWindow");
                },
                teardown: function () {
                    // Restore the actual jQuery/Kendo functionality by clearing the sandbox
                    sandbox.restore();

                    // Re-close the dialog box
                    $("#message").data("kendoWindow").close();
                }
            });


        test("displayMessage opens a Kendo window and replaces the inner contents", function () {

            // ** Prepare input **
            var title = "some title";
            var message = "<p>The detailed message</p><p>with HTML in it</p>";

            // ** Call the system under test  **
            // That is, call the function "displayMessage"
            displayMessage(message, title);

            // ** Evaluate the results **

            // Were the spies used?
            ok(jQueryHtmlSpy.calledOnce, "HTML should be injected");
            ok(kendoWindowSpy.calledOnce, "dialog window should be opened");

            // Now let's dig into the details a bit... first making sure the desire message was injected
            ok(jQueryHtmlSpy.calledWithExactly(message), "desired message not passed");

            // Next, let's look at the arguments passed to the KendoWindow. I don't want to
            // look at all the arguments - that would feel like overspecification to me.
            // So let's just test that the JSON-formatted arguments include the modal setting
            // and that the input title is injected as desired.
            var args = kendoWindowSpy.firstCall.args[0];

            //var actual = JSON.parse(args);

            ok(args.modal, "modal property");
            equal(args.title, title, "title property");
        });

    <button id="showMessage">Show Message</button>
    <div id="message">this text will be replaced with a dialog box containing new text</div>
    <hr />
    <!-- Standard setup for Qunit is -->
    <h1 id="qunit-header">QUnit Test Results</h1>
    <h2 id="qunit-banner"></h2>
    <div id="qunit-testrunner-toolbar"></div>
    <h2 id="qunit-userAgent"></h2>
    <div id="qunit"></div>
    <div id="qunit-fixture"></div>