Resharper on the fly code analysis from Jetbrains

What is Resharper?

ReSharper is a popular developer productivity extension for Microsoft Visual Studio. It automates most of what can be automated in your coding routines. It finds compiler errors, runtime errors, redundancies, code smells, and possible improvements right as you type, suggesting intelligent corrections for them. ReSharper helps explore code by visualizing the structure of files, type and style hierarchies, call and value chains, project dependencies. It allows instantly traversing your entire solution and jumping right to the exact file and line that we are looking for, decompiling library code if necessary. Dozens of solution-wide refactoring’s are available to help safely change code base. Code formatting and cleanup features allow to get rid of unused code and help your entire team to ensure compliance to coding standards.

Why Resharper?

With unparalleled support for C#, VB.NET, XAML, JavaScript, XML, HTML, CSS, ASP.NET, ASP.NET MVC, NAnt and MSBuild scripts including comprehensive cross-language functionality, ReSharper will help any Visual Studio user write better code, easily examine and refactor existing code bases.We can spend less time on routine, repetitive manual work and instead focus on the task at hand. A robust set of features for automatic error-checking and code correction cuts development time and increases your efficiency. We'll find that ReSharper quickly pays back its cost in increased developer productivity and improved code quality. With ReSharper, .NET developers can truly experience what we mean when we say "Develop with pleasure!"

Resharper Advantages

1. No need to In-depth Analysis of C# Code.
2. Advanced Coding Assistance.
3. Numerous Code Refactoring’s.
4. Navigation and Search.
5. Code Cleanup.
6. Cross-Language Functionality.
7. ASP.NET page intelligence Support.
8. XML Support.
9. XAML Support.
10. Integrated Unit Testing.
11. NAnt and MS Build Scripts Editing.
12. Find unused members of a class like Methods, Properties and Variables.
13. Suggestions like converting a LINQ expression into a Lambda expression.
14. While using String.Format method, Resharper can validate that the placeholders match the supplied values.
15. While using logical constructs like If Else it can suggest better options.
16. When using multiple if statements it can refactor into a Switch case loop.
17. With methods which return values, and if we are using If Else construct to return two different values based on certain conditions then Resharper can suggest changes to redundant else conditions.
18. Based on the usage of methods, Reshaper can suggest changing the methods to static methods or even the variables to read-only variable.

Comparison among Resharper, FxCop and Stylecop

S. No.	Feature	Resharper	FxCop	StyleCop
1	Analyzes managed code assemblies	No	Yes	No
2	Localization	Yes	Yes	Yes
3	Detecting performance issues	Yes	Yes	Yes
4	Security improvements	Yes	No	No
5	Design rules set	Yes	Yes	Yes
4	Design Guidelines for Class Library	Yes	Yes	Yes
5	Execute on	Windows and command line both	Windows and command line both	Windows and command line both
6	Work with	C#/VB.Net/Linq/Asp.net/ EJB/ JSP/ JSF/CSS/JavaScript	Complied DLL	Only C# File
7	Works With Assemblies	No	Yes	No
8	Handel Exception	Yes	Yes	No
9	Unit Testing	Yes	No	No
10	Checks Code on fly	Yes	No	No
11	Create Class File	Yes	No	No
12	Licensee	Required	Free	Free
14	Code Analysis format	XML	XML	XML
15	Locating the “Dead” Code	Yes	No	No
16	Analyzing Code Dependencies	Yes	No	No
17	Suppressing inspections for the code	Yes	No	No
18	Value Tracking	Yes	No	No
19	Call Tracking	Yes	No	No
20	Navigating Between Highlighted Code	Yes	No	No
21	Quick-Fixes errors	Yes	No	No
22	Code Refactoring	Yes	No	No
23	MVC Support	Yes	No	No
24	Dynamic Language support	Yes	No	No
25	Code Cleanup	Yes	No	No
26	Cross-language functionality	Yes	No	No

FxCop:

FxCop is an application that analyzes managed code assemblies (code that targets the .NET Framework common language runtime) and reports information about the assemblies, such as possible design, localization, performance, and security improvements. Many of the issues concern violations of the programming and design rules set forth in the Design Guidelines for Class Library Developers, which are the Microsoft guidelines for writing robust and easily maintainable code by using the .NET Framework.
FxCop is very similar to Visual Studio Code Analysis. FxCop can be run as either a Windows application or at the command line.

StyleCop:

StyleCop is similar to FxCop, but it provides a different function and is, in fact, complementary to either FxCop or Code Analysis. (Note that it only works on C# source files.) It is mostly concerned with coding style and formatting. As such, it is run against source files, not assemblies like the other two analysis tools.

Conclusion:

ReSharper provides continuous code quality analysis in C#, VB.NET, XAML, XML, ASP.NET, ASP.NET MVC, JavaScript, HTML, and CSS, detecting errors and problems before you even compile. 

I’ve been using Resharper since last 3 years in .NET/C#. It’s a tool with a lot of features which aids you in the average day development and after comparing all others code analysis tool recommended to use Resharper,since it gives you on the fly code analysis and instant code refactoring.

What is faking framework?

Microsoft faking is an isolation(mocking) framework that allows us to mock the static,sealed method without rewriting any implementation code. The mocking is primarily used in unit testing. An object under test may have dependencies on other (complex) objects to resolve that dependency in unit testing we need to mock. If we have dependency of other component in project, then we need to implement mocking for automated unit test cases.The benefits of MS fakes are easy to write unit tests and less refactoring time, although at the expense of maintaining tightly-coupled code.

Available frameworks for mocking.

There are lots of framework available for mocking like 

• MOQ
• Rhino
• Moles
• Faking (new in MS VS 2013)

Comparison among MOQ, Moles, Rhino and MS Faking framework

S. No.	Feature	MOQ	Moles	Rhino	MS Faking framework
1	Licensing	Free	Free(MS VS Gallery)	Free	Free(VS 2013 Ultimate and Premium)
2	Can Mock: Interface	Yes	Yes	Yes	Yes
3	Abstract class	Yes	Yes	Yes	Yes
4	Event	Yes	Yes	Yes	Yes
5	Exception	Yes	Yes	Yes	Yes
6	Concrete class virtual methods/properties	Yes	Yes	Yes	Yes
7	Concrete non virtual member	No	Yes	No	Yes
8	Static Class	No	Yes	No	Yes
9	Sealed Class	No	Yes	No	Yes
10	Protected Virtual	No	Yes	No	Yes
11	Supports callback on mock method	Yes	Yes	Yes	Yes
12	Supports multithreading exception	No	Yes	Yes	Yes
13	Supported version	3.5/4.0	2.0/3.5/4.0	1.1/2.0/3.0/3.5	4.5
14	Support Linq	Yes	Yes	Yes	Yes

Background of Faking Framework

The fake framework in VS 2013 is next generation of moles and stubs and will eventually replace the Moles features. 

• A stub replaces a class with a small substitute that implements the same interface. To use stubs, we have to re-design our application so that each component depends only on interfaces, and not on other components. By "component" we mean a class or group of classes that are designed and updated together and typically contained in an assembly.

• A shim modifies the compiled code of our application at run time so that instead of making a specified method call, it runs the shim code that our test provides. Shims can be used to replace calls to assemblies that we cannot modify, such .NET assemblies. 

Integrate VS 2013 with MS Fake Framework

Fake framework have two components

1. Stub's.
2. Shims.

When we are mock object or methods using stub's we need to design our class structure according to stub's rule,each class should inherited to interfaces.

Integration with Visual Studio

To start writing unit test cases using MS Fake we need to add Faking framework library.

Right click on Add reference of test project > click on browse tab >click on browse button > give that path to add faking dll

"C:\Program Files (x86)\Microsoft Visual Studio 12.0\Common7\IDE\PublicAssemblies\Microsoft.QualityTools.Testing.Fakes.dll". 

Note:

MS Fakes framework is only available in Ultimate and premium edition as of now.Compare chart of VS product

The integration with Fakes with Visual Studio 2013 is brilliant. To create a "fake" of an assembly, we needs to just right click on the references and click the option "Add Fake Assembly" in test project.

When we add a fakes assembly in our test project by right clicking on the reference assembly and clicking the "Add Fakes Assembly" option, visual studio adds the following files.

1. A new "Fakes" folder is created with a .fakes files created in it. For example, if we are creating fakes for "System.Configuration", a file called "System.Configuration.fakes" will be created.
2. A new "FakesAssemblies" folder is created with three files created.

1. originalAssembly.assemblyversion.Fakes.dll
2. originalAssembly.assemblyversion.Fakes.xml
3. originalAssembly.assembly.Fakes.fakesconfig. 

So, for "System.Configuration" assembly the files generated would be System.Configuration.4.0.0.0.Fakes.dll,System.Configuration.4.0.0.0.fakes.xml and System.Configuration.4.0.0.0.Fakes.fakesconfig 

Visual Studio also adds a reference to the generated assembly in the "FakesAssemblies" folder.The "FakesAssemblies" folder and all the files in it are generated whenever the project is compiled. This is important because if we are adding fakes for assembly for a changing component, the generation of FakesAssemblies will ensure that all changes are reflected in the generated assembly. 

After adding successful faking dll(s) system will add one more dll named mscorlib.4.0.0.0.Fakes.

Note that mscorlib.4.0.0.0.Fakes assembly contains a special type called Shims. Shims are strongly typed wrapper that allows to replace .NET types with delegates.

Structure of a unit test project:

Structure of Unit test project looks like below screen.

Left part of screen is test execution result.

Right part of screen is structure of test project.

Middle part of screen is actual unit test case.

To execute test cases just right click of test method and choose "Run test" or go to Test > Run >All test

Structure of Unit test case

[TestClass] public class ThingTest { // Setup // Exercise // Verify // Teardown [TestMethod] public void TestSomething() { } }

Create Bootstrap 

Create Setup ( all required db object) to execute Test case.

How to use Shims

Attributes of unit test method

MSTest Attribute	Purpose
[TestMethod]	Identifies of an individual unit test
[TestClass]	Identifies of a group of unit tests, all Tests, and Initializations/Clean Ups must appear after this declaration
[ClassInitialize]	Identifies a method which should be called a single time prior to executing any test in the Test Class/Test Fixture
[ClassCleanup]	Identifies a method in to be called a single time following the execution of the last test in a TestClass/TestFixture
[TestInitialize]	Identifies a method to be executed each time before a TestMethod/Test is executed
[TestCleanUp]	Identifies a method to be executed each time after a TestMethod/Test has executed
[AssemblyInitialize]	Identifies a method to be called a single time upon before running any tests in a Test Assembly
[AssemblyCleanUp]	Identifies a method to be called a single time upon after running all tests in a Test Assembly
[Description]	Description about test method.
[TestCategory]	Defines the category of test method, it could be positive or negative.
[DataSource]	Define the data source of test method by which method gets the data and execute the logic. It could be XML,CSV or Database
[DeploymentItem]	Specify a file or directory that should be deployed along with the assemblies before running a test. Attach this attribute to a test class or test method. We can use multiple instances.

Modifications required to Project 

If we mock the object or class by using "Shims" then no need to change anything in solution, but when we use "Stubs" then we have to re-design structure of solution inherits all the classes from interface.

Challenges/Issues and possible workarounds

• When we adds the fake assembly of main project exe/dll (which we want to write unit test case) the "Project.fakes" file add in Fakes folder into test project. Might be possible its throw an error, if an error thrown by system during build, the cause of issue could be test projects fakes gives compilation error. The exact error is given below.

"Could not resolve this reference. Could not locate the assembly "System.Configuration.4.0.0.0.Fakes". Check to make sure the assembly exists on disk."

The error would go away if I added the FakesAssemblies folder in Source control.after detailed analysis found the reason of error happened was because the “Build action” for the ".fakes" file added to the project was not set correctly. These files should have the build action set to "Fakes" instead of "None".

 before set build action ="Fakes" it was

• MS-Fakes work only Ultimate or premium edition,i have install professional edition and found it not works.
• Open AssemblyInfo.cs of main project  and add [assembly: InternalsVisibleTo("UnitTestProject")] as below screen
• 
  
• When we play with external data source like XML to execute our test case we need to add reference of "System.Data" by right click on Reference > Add reference otherwise we can not read data from xml file.
• After code was written to get the test values from external data source, I could not get the result like below screenshot. Following are the common issues that may encounter and here is the solution:
  Issue: The unit test adapter failed to connect to the data source or read the data.
• 

Solution : Go to the Solution Explorer, add new item into solution, then select "Test Settings" from the left menu, then add a new test setting.

In the "Test Settings" window, select "Deployment" from the left menu, then check the "Enable Deployment" check-box and click on apply.

If problem still persist,then go to Solution Explorer, locate  test data XML file and then open the file properties. Make sure the "Copy to Output Directory" property is NOT set to "Do not copy", make it either "Copy always" or "Copy if newer". like below screen

After doing all above steps,it works.

Conclusion

Unit testing is a major component of every project. The early feedback receive from our tests help us feel confident that we didn’t introduce new bugs, and that we gave to QA actual working code.Faking framework helps us to mock the dependent complex module like email server,database layer etc and we don't need to implement dependency injection and don't need to create fake by inheritance.Every faked instance looks and feels like an instance of the faked type.After comparing all others mocking frameworks available in market MS faking framework gave us to more feature rather than others.Hence it is highly recommended to use MS fakes into project to gave the better delivery of the code.