AutoConstruct

Tool for auto inject mocks into constructors during test. Minimizes required setup code.

Rationale

If a class has many constructor dependencies, it becomes increasingly impractical to unit test the class, as each instantiation will require the setup of many mocks. It is entirely possible that a method that is being tested, does not depend on all constructor dependencies. In such cases, having the setup of all those dependencies/mocks is too impractical.

Another advantags is that if the contructor dependencies changes for a class that has many unit tests, it will still compile, enabling red/green testing without having to "fix" all constructor calls.

Usage

Remarks

Once an instance has been created of the specified type, this ConstructorContext is used, and cannot be used again. Each object needs its own ConstructorContext.

Example

This is an example of how the class may be used. Given the types:

public interface ISomeInterface {
     void SomeOperation();
}

public class Class {
    private readonly ISomeInterface m_i;

    public Class(ISomeInterface i) {
       m_i = i;
    }

    public void DoStuff() {
       m_i.SomeOperation();
    }
} 

We can write tests like this:

var context = new ConstructorContext<Class>();
var mock = context.Inject(new Mock<ISomeInterface>());

mock.Setup(m => m.SomeOperation());

var objectUnderTest = context.New();
objectUnderTest.DoStuff();

Dependencies

This project depends on Moq.