# How to stub an interface in test-case?

1. Include scalamock library dependency i.e. "org.scalamock" %% "scalamock-scalatest-support" in the project's custom.sbt

2. Extend the test-suite to implement MockFactory interface.

3. grab the stub using keyword stub

   
   
   
   

    

   
   
   
   

   import org.scalamock.scalatest.MockFactory
   
   class CreateCommandTestSuite extends FunSuite with SmilePerTest with MockFactory {
     val lotteryDomainStub = stub[LotteryDomainLogic]
   	...
   }
   

4. set the Binder for the test-case by binding the stub to the testcase name

    

   
   
   
   
   

   setBinderFor("create first lottery", bind[LotteryDomainLogic].toInstance(lotteryDomainStub))
     test("create first lottery", Tag("create"), ptest) {
     ...
     }
   

5. Inside the testcase provide the stub implementation:

   For example, in order to make the api isOpenToRun return true when you pass lottery name as "TestLottery" :

   
   

    

   
   
   
   

   test("create first lottery", Tag("create"), ptest) {
       (lotteryDomainStub.isOpenToRun _).when("TestLottery").returns(true)
       ...
   }
   

   Note: You can also use wildcards like * inside when