Starting an InPrivate instance of Internet Explorer in CodedUI

Mario Majcica March 20, 2015 1 Comments

During the preparation of one of my CodedUI tests I came in situation in which I needed to start Internet Explorer with InPrivate Browsing set to active. There is no such a property on BrowserWindow object that can be set, probably because this is a specific Internet Explorer option (although present as functionality with a different name on other browsers). So how do we do it?

A quick search on Google, surprisingly, didn’t gave any results. So I dug into this small challenge.

In order to start Internet Explorer with InPrivate Browsing set to active it is necessary to pass the -private argument to the call of the executable. So how to pass an argument to the BrowserWindow instance that we are creating?

It’s not obvious as not often used but, BrowserWindow.Launch static method has, aside the usual signature accepting an Uri object as a parameter, an overload that accepts a variable number of string  arguments (params string[]). The string arguments specified in the call of this method, will be passed as arguments to the process that is going to be started by invoking the BrowserWindow.Launch, in this case to the process of Internet Explorer. This is quite handy as we can pass our URL and and the necessary -private argument to Internet Explorer and achieve the desired result.

BrowserWindow.Launch("http://www.google.com/", "-private");

How does it work?

If you peek inside the BrowserWindow class, you will see that underneath it is starting a process and it passes all of the parameters as an array of string to the Arguments property.

Process process = 
    new Process {StartInfo = {FileName = "iexplore.exe"}};
StringBuilder commandLine = new StringBuilder();
Array.ForEach(
    arguments, 
    str => commandLine.AppendFormat(
        CultureInfo.InvariantCulture, 
        "{0} ", 
        new object[] { str }));
process.StartInfo.Arguments = commandLine.ToString();
process.Start();

The same can be achieved also by using the following approach:

Process ieInPrivate = new Process();
ieInPrivate.StartInfo.FileName = "iexplore";
ieInPrivate.StartInfo.Arguments = "http://www.google.com/ -private";
ieInPrivate.StartInfo.WindowStyle = ProcessWindowStyle.Maximized;
ieInPrivate.Start();

BrowserWindow browser = BrowserWindow.FromProcess(ieInPrivate);

At the end the result will be a successfully launched Internet Explorer with InPrivate Browsing set to active.

There are also some other handy option that you can pass to Internet Explorer like -extoff that will start Internet Explorer in No Add-ons mode. For a complete list of options check the following page on MSDN.

Happy coding!

Installing VSIX package via WiX installer

Mario Majcica February 4, 2015 0 Comments

Introduction

WiX Toolset is a powerful set of tools used to create Windows installations packages. Unfortunately it’s learning curve is quite steep and the documentation is not it’s strong point. That’s why I decided to show you, step by step, how to create an installer for your VSIX packages. I will not cover all of the WiX features as this is not intended to be an exhaustive WiX guide but I will describe in detail what is necessary to deploy a VSIX package. Also I will add some interesting details that can be useful more in general when creating WiX installers. The end result should be a MSI installation file that will correctly install and uninstall your VSIX package. Let’s start.

It’s true that VSIX leverages an installer on it’s own. Still you should consider this approach if your installation is more complex and/or requires other components to be installed.

Prerequisites

In order to follow this example you will need any version of Visual Studio starting from 2010 till the most recent 2015. Also any sku except the Express is fine. You will need a Visual Studio SDK and WiX Toolset installed. The examples you will find are made w Visual Studio 2013 and WiX 3.9 R2. You can download them from here (SDK and WiX).

Creating the necessary projects

In order to start our practical example, let’s first create the necessary project that we are going to use by our installer later. Create a new project in Visual Studio and choose a “VSIX Project”.
I will name it MyAwesomeExtension.

Once the project is created you will be presented by the vsixmanifest designer. You can leave all the defaults. Make sure only that the Product ID is set in the unique way and that, for commodity, it doesn’t contain spaces.

This should be it for what concerns our extension. I will not focus on creating Visual Studio extensions and this is just enough to have an extension registered and working. If you hit F5 you should start another instance of Visual Studio, by default in Experimental Mode, and if you check inside Tools > Extensions and Updates menu you should find your newly created extension.

The next thing is adding a WiX Setup Project into your solution. I will simply call it Installer.

This was about it. In the next paragraph I will show you how to install your VSIX package using WiX.

WiX Toolset installer

First thing first. We are going to take advantage of a standard custom action offered by WixVSExtension. In order to do so, we need to reference the WixVSExtension.dll. You can find it inside the WiX installation folder which in my case is C:\Program Files (x86)WiX Toolset v3.9bin. Be aware that the Add reference panel for the WiX setup projects is custom and it slightly differs from the default one. Aside of having the necessary to help us installing (and uninstalling) VSIX packages, it also contains many other useful properties and custom actions that will ease interacting with Visual Studio. You can find a list of the properties and custom actions here.
After the reference to the project is added we need to include the WixVSExtension namespace in our main wxs file (by default Product.wxs). In the Wix element next to the default namespace add the following xmlns:VSExtension="http://schemas.microsoft.com/wix/VSExtension". The end result should look like this:

...

Now we are going to add another reference to our Wix project and it will point to our VSIX project. This is done for commodity so that we can point Wix to the output of our VSIX project. Once this is done we need to define a component that will leverage the custom action defined in WixVSExtension that will actually install our VSIX. Inside the fragment where an example of ComponentGroup is defined, we are going to remove all of the code inside it, comprehensive of ComponentGroup itself. Define the following:

Let’s analyze what we added.
First element we added is a Component, that we called for convenience C_MyAwesomeExtension, we assigned a unique identifier to our component (so that MSI can track this element) and we specified the folder in which this component should be deployed. I will not get into details of what a component is and how it works, I do suppose you already know that and if not you can find more info here.

Inside our component we specified two elements. The simpler one to understand is for sure the File element. We gave an id to the file that we do need in order to deploy our VSIX and named it by using the name of the compiled assembly. In order to retrieve the name I used a variable that was generated by Wix because of the reference to the project we added, appending to the result the .vsix string. Now, each time you reference a project Wix will create several variables dynamically and they will be at your service. A full list of them you can find at this link. In case we were referencing a project that will output an executable or a library, we could use the TargetFileName variable and omit the .visx. However as by default Wix doesn’t know nothing about VSIX project types and outputs, we need to use TargetName property and concatenate .vsix to it in order to get a file name with the correct extension.

Same thing we did with the source attribute. With it we do specify where this file should be copied from in order to be placed inside the MSI installation file. As for the Name attribute, we are going to use some of auto generated variables to get to the correct path of our compiled VSIX.

VSExtension:VsixPackage element

Let’s focus on the main character of this article, the VSExtension:VsixPackage element. I will describe all of the attributes I used and also the one I haven’t and describe the behavior that they do produce.

File
File, as the name suggest, requires to be set to the file name that we used in our MSI tables and points to our VSIX installer. Simply said it needs to be the same as the Id attribute we used for the File element that we discussed earlier. In this way the custom action will know where is the VSIX file that we are planning to install.

PackageId
This is a very important value. Earlier I mentioned the Product ID, when we were creating our VSIX extension. Well that’s it, the unique product ID that is set inside vsixmanifest file in your extension. Make sure that it does not contain any spaces and if so add quote marks and escape them properly.

Target
You can specify one of the following values: integratedShell, professional, premium, ultimate, vbExpress, vcExpress, vcsExpress, vwdExpress. It will indicate which edition (SKU) of Visual Studio is required in order to register this extension.

TargetVersion
Specifies the version of Visual Studio for which to register the extension. Should contain a version number as at example 11.0 in case of Visual Studio 2012 or 14.0 in case of Visual Studio 2015.

Vital
In indicates if the failure of the installation of the VSIX extension will cause a rollback of the whole installation.

Permanent
Often underestimated and forgotten parameter. This is the reason of many complains about the extension not uninstalling on msi uninstall. And that’s all about it. If set to no, your extension will be uninstalled once you try to uninstall your product. If set to yes, your extension will not be removed in case the user uninstalls the product.

VsixInstallerPathProperty
As this custom action relies on VsixInstaller.exe to trigger the installation of the VSIX, it needs to know where the VsixInstaller.exe is located in order to use it. It is recommended not to set this attribute and let it be populated by the custom action itself. By default, the latest VsixInstaller.exe on the machine will be used to install the VSIX package.

Believe it or not this is sufficient to let the Wix install your VSIX extension. In our case we do target the Visual Studio 2013 and accepting any edition from professional above.

Behind the scene

So what’s the magic behind this custom action? The simplest way to verify what is happening is to compile our project and launch the installation. Before we are able to this there are two minor things we need to take care of. Inside our Feature element we need to change the ComponentGroupRef to ComponentRef and point the id to our C_MyAwesomeExtension component. Also to make the output a single file, we will tell Wix to integrate the cabinet inside the msi itself. To do so under the MediaTemplate element we are going to add the EmbedCab attribute and set it’s value to yes.

We can compile now our project and position our self in the build output directory. A file called Installer.msi should be there.
In order to see what is happening we can’t just double click our newly created msi. We need to launch the installation from the command prompt and request the verbose logging to be activated. To request the log file being emitted we need to launch the following command: msiexec /i Installer.msi /l*v install.log. This will tell the msi installer to install our application and output a verbose log inside the file named install.log.
If you execute this command, you will briefly see installation starting and that’s it. This is because we haven’t chosen any UI for this installation. It’s not in our scope showing how to create/choose and UI for the installer.
Let’s check our default install folder at C:\Program Files (x86)Installer. Bingo! Our extension is there. Now open your Visual Studio 2013 instance and check the Extensions and updates window. Again, MyAwesomeExtension is there!

Open the newly created log file to see what was done in order to achieve this. Open the install.log file and search for “/skuName:Pro /skuVersion:12.0”. The line you landed on is the command that was executed by our VSExtension:VsixPackage custom action. The full command is following:

C:\Program Files (x86)Microsoft Visual Studio 12.0Common7IDEVSIXInstaller.exe /q /skuName:Pro /skuVersion:12.0 “C:\Program Files (x86)InstallerMyAwesomeExtension.vsix” /admin

What happened here? Well nothing special. When you double click your vsix file, the vsix extension is associated with VSIXInstaller.exe and it will show you the following window:

Same thing with our custom action, it calls directly VSIXInstaller.exe and triggers the quite mode (so no UI is shown) and passes the necessary parameters in order for VSIXInstaller.exe to preform the installation. Do you recognize the other parameters? That’s right, the do match what we have specified with the attributes on our VSExtension:VsixPackage element. Execept the last /admin parameter. It implies that the extension will be installed to the admin extension location. If you prefer it to be installed on per user basis, you will need to create a perUser installation, thus, set the Package InstallScope to perUser.

You can get through the log file and probably you will find plenty of interesting information, like the search for the VSIXInstaller.exe and the values that are set in order to accommodate it, etc.

The same thing is done for what concerns the uninstall. We can launch the uninstall with the following command: msiexec /x Installer.msi /l*v unistall.log. As you can see it is similar to the install except that instead of /i we used a /x parameter. Once you execute it you will be prompted for the confirmation:

By confirming that, the uninstallation will be preformed.

Get inside the log file and search again for /skuName:Pro /skuVersion:12.0. You will land on line that triggers the following command:

C:\Program Files (x86)Microsoft Visual Studio 12.0Common7IDEVSIXInstaller.exe /q /skuName:Pro /skuVersion:12.0 /u:”MyAwesomeExtension.majcica.com.420d4ff9-340c-4867-9247-c85ab370ec7b” /admin

Please notice that the /u parameter is passed which will indicate to VSIXInstaller.exe to remove the extension with product Id (and not the vsix file anymore) that matches the unique ID of our extension.

Tuning the installer

There are a couple of things we could take care of. One of them is to check if the requested Visual Studio is installed. This in order to prevent an eventual exception and a consequent installation failure. As this is fairly simple I will add the necessary info to this post.

Everything we need to know about the Visual Studio been installed. WixVSExtension puts on our disposition this info in form of a property. In case Visual Studio is installed, the property will be populated, otherwise will not. Only thing we need to do is to reference the property, which in our case is called VS2013DEVENV, and create a condition that verifies if it is set.

After adding this code inside the product element, compile, and launch your installation, you will get the following message, which eventually will interrupt and prevent the installation.

Another thing I can think of is installing the extension to multiple versions of Visual Studio. You could declare several components, each one targeting the same file but different TargetVersion, and add a condition to each of them. Example:

  VS2012DEVENV
  



  VS2013DEVENV
  

Conclusion

I hope I answered all of the questions you may have regarding installing VSIX packages via Wix. If there is anything I omitted and you would like to know more about, please do not hesitate to ask in the comments.
For completeness I will now list the complete content on the Product.wxs file.

Happy coding!

moq.Callback(), The Unknown

Mario Majcica October 14, 2014 0 Comments

Introduction

More and more often I do see people having trouble testing certain type of code. As a result, code coverage is dropping down, unverified logics are shown up, lowering the quality and rising frustrations. This is what pushed me to write this post and describe this kind of situations and a decent solution to it.
This kind of situations are commonly found in all the cases in which the tested unit manipulates the arguments that are passed to our mock. In this case we need to verify that this transformation did what we expected it to do. However, it ain’t that simple and straightforward as it seems. As code speaks more than thousand words, let’s illustrate this with an example.
Consider the following class:

public class ProductService
{
    private readonly IOrderRepository m_orderRepository;

    public ProductService(IOrderRepository orderRepository)
    {
        m_orderRepository = orderRepository;
    }

    public List GetProducts(int customerId, int orderId)
    {
        OrderSearchCriteria orderSearchCriteria = new OrderSearchCriteria
        {
            OrderId = customerId // THIS IS THE PROBLEM WE ARE GOING TO SEARCH FOR

            // Set some other search criteria...
        };

        Order retrievedOrder = m_orderRepository.GetOrder(orderSearchCriteria);

        // Do something else
        return retrievedOrder.Products;
    }
}

What you can see here is a hypothetical product service that we are going to test. More precisely we are going to write unit tests for the GetProducts method. What this method does in particular is composing another object that will be passed to our dependency, the order repository. Now you can argue that this is a bad practice, that the object composition should be handled in a different manner, as usually in this cases the single responsibility principle is not met. And you are right, but we do not live in a perfect world and often we can’t easily change what is already there. However, we need to keep extending and improving our software.

Still, I do need to write a test for that method. What should I do, how do I spot this bug that we just introduced?

There are two ways of writing a unit test that will test, verify and spot our bug. Let’s start with the first one.

Shaping an expected instance

We can tackle this problem by setting up manually, in our test, an instance of OrderSearchCriteria class, as we expect it to be, base on the parameters that we are passing in, and make sure that our mock accepts only an instance that equals ours, on purpose created class.

Let’s check our unit test.

[TestMethod]
public void GetProducts_Creates_OrderSearchCriteria_Correctly()
{
    const int customerId = 56789;
    const int orderId = 12345;

    OrderSearchCriteria orderSearchCriteria = new OrderSearchCriteria
    {
        OrderId = orderId
    };

    Mock orderRepositoryMock = new Mock();
    orderRepositoryMock
        .Setup(m => m.GetOrder(orderSearchCriteria))
        .Returns(new Order());

    ProductService sut = new ProductService(orderRepositoryMock.Object);

    List result = sut.GetProducts(customerId, orderId);
}

Now, first thing first. In order this example to even work, your parameter class needs to implement the equality members. This is necessary as Moq, in order to determine equality of parameters, rightly, relays on Equals() method.

Another disadvantage of this technique is the fact that construction of our own object can sometimes be hard or even not possible. Not to even mention the maintenance problem we are going to introduce.

As Moq in the case of wrong parameter will return a null from the method call, often null value is managed and interpreted as a possible state. In that case it will be very hard or impossible to discover our bug.
Luckily there is a cleaner way to approach this kind of situations.

Extracting the parameter via Callback method

As it is not often used, many developers tend to ignore the Callback method that is provided by Moq framework. In this kind of situations it can be very handy.

Check out the following test.

[TestMethod]
public void GetProducts_Creates_OrderSearchCriteria_Correctly_2()
{
    const int customerId = 56789;
    const int orderId = 12345;

    OrderSearchCriteria recievedOrderSearchCriteria = null;

    Mock orderRepositoryMock = new Mock();
    orderRepositoryMock
        .Setup(m => m.GetOrder(It.IsAny<OrderSearchCriteria>()))
        .Returns(new Order())
        .Callback(o => recievedOrderSearchCriteria = o);

    ProductService sut = new ProductService(orderRepositoryMock.Object);

    List result = sut.GetProducts(customerId, orderId);

    Assert.IsNotNull(recievedOrderSearchCriteria);
    Assert.AreEqual(orderId, recievedOrderSearchCriteria.OrderId);
}

You can see that I’m setting up my mock and I’m specifying what the callback should do. What I’m telling him in this case is that for the parameter of type OrderSearchCriteria, once the method is invoked, copy it to the locally defined object called recievedOrderSearchCriteria. This will give me the possibility to check what came in the call of the GetOrder method, and verify that is what I expect to receive.
Once I start my assertions I do a check on the recievedOrderSearchCriteria and I do make sure that what came in, is what I do expect.

This test will fail and we will succeed in our intent. Also the message that we are receiving is far way clearer than one in the previous example. It states at this moment

Assert.AreEqual failed. Expected:<12345>. Actual:<56789>.

Beside this we are actually asserting the expected result thus specifying behavior in an explicit way.
Now, this on my opinion is much better!

Other considerations about the Callback method

For a less experienced developers, I’ll also make an example of how to get a callback working if you have more then one parameter accepted by your mocked object.
I’m going to extend our IOrderRepository interface by adding a overload of the GetOrder method that accepts two parameters. Also I will implement another method on ProductService class that uses this newly created method.

public interface IOrderRepository
{
    Order GetOrder(OrderSearchCriteria searchCriteria);

    Order GetOrder(int orderId, bool archieved);
}

public List GetProducts(int orderId)
{
    Order retrievedOrder = m_orderRepository.GetOrder(orderId, true);

    return retrievedOrder.Products;
}

In order to mock my order repository and have on callback the necessary values, the following test is used.

[TestMethod]
public void GetProducts_With_Archieved_Orders()
{
    const int orderId = 12345;

    int receivedOrderId = 0;
    bool receivedArchieved = false;

    Mock orderRepositoryMock = new Mock();
    orderRepositoryMock
        .Setup(m => m.GetOrder(It.IsAny(), It.IsAny()))
        .Returns(new Order())
        .Callback((o, a) =>
        {
            receivedOrderId = o; 
            receivedArchieved = a;
        });

    ProductService sut = new ProductService(orderRepositoryMock.Object);

    List result = sut.GetProducts(orderId);

    Assert.AreEqual(orderId, receivedOrderId);
    Assert.AreEqual(true, receivedArchieved);
}

As you can see, I just added an extra type in my generic definition and then adjusted my lambda expression accordingly. If more than two parameters are required, you can just follow the same pattern and define them as many as need. At example .Callback((o, a, i) etc.

You always need to respect the exact parameter signature of the method you are setting up. The number of parameters accepted by the mocked method need to mach in type, order and number the parameters accepted by your mocked method.

There is another way to express the same statement, just by using the lambda expression instead of generics. I can rewrite the above examples in the following way:

.Callback((OrderSearchCriteria o) => recievedOrderSearchCriteria = o);

// ...

.Callback((int o, bool a) =>
{
    receivedOrderId = o;
    receivedArchieved = a;
});

The effect is the same, it is only about your preference which of the two ways to use.

It is also possible to define it before and after the method invocation and as I can’t think of a nice example I will just provide the one from the Moq documentation:

// callbacks can be specified before and after invocation
mock.Setup(foo => foo.Execute("ping"))
    .Callback(() => Console.WriteLine("Before returns"))
    .Returns(true)
    .Callback(() => Console.WriteLine("After returns"));

Conclusion

Each time you need to check the arguments that are passed to the method you are setting up, Callback() will help you get to them. Also, if you need to execute any code before or after the method is invoked, Callback() will let you do so.
Hopefully you are not going to use it on a daily basis, but it is handy to know about it as sooner or later you are going to face a situation where a Callback() will help you achieve your goal.