How to test Grails service using Spock?

Question

I have a EncouragementService.groovy with following method

  class EncouragementService {
   def stripePaymentService 

   def encourageUsers(List&l         


        

Answer 1

Service class can be optimized as below:

class EncouragementService {
   def encourageUsers(List<User> users){
       if(users){ //Groovy truth takes care of all the checks
          for(user in users){
            //logic
          }
       }   
   }
}

Spock Unit Test:
Spock takes testing to whole another level, where you can test the behavior (adheres to BDD). The test class would look like:

import spock.lang.*

@TestFor(EncouragementService)
@Mock(User) //If you are accessing User domain object.
class EncouragementServiceSpec extends Specification{
  //def encouragementService //DO NOT NEED: mocked in @TestFor annotation

  void "test Encourage Users are properly handled"() {
      given: "List of Users"
          List<User> users = createUsers()

      when: "service is called"
          //"service" represents the grails service you are testing for
          service.encourageUsers(users) 

      then: "Expect something to happen"
          //Assertion goes here
  }

  private def createUsers(){
       return users //List<User>
  }
}

Answer 2

Use the build-test-data plugin to build the users.

@TestFor(EncouragementService)
@Build(User)
class EncouragementServiceSpec extends Specification {

  def "encourage users does x"() {
    given:
    def users = createUsers();

    when:
    service.encourageUsers(users)  

    then:
    // assert something
  }

  def createUsers(){
    [User.build(), User.build(), User.build()]
  }
}

I've also made a couple of changes to the code to make it a proper spock specification. Your test has to extend Specification and you might want to familiarize yourself with Spock's keywords.