如何在Spock单元测试Grails中测试catch块代码

Question

Hi i am having my controller action like this and i want to test the catch block of my action tst with the help of Spock Controllers Unit test in Grails

class AbcController{
       def tst(Long id) {
       Abc abc =  Abc.get(id)
          try{
            ................
            println "Try block"
            ..................
          }
          catch(DataIntegrityViolationException e){
            ........
            println "Catch block"
            ........
          }
      }    
}

My test case is like.

@TestFor(AbcController)
@Mock([Abc])
class AbcControllerSpec extends Specification {
  void 'Test action catch block'() {
    setup:
      params.id = 1
    when:
      controller.tst()
    then:
      thrown DataIntegrityViolationException
    expect:
      1==1
  }
}

But the Catch block code is not executing at all please help me in doing so.

Answer 1

You would need to throw an exception in your test case. You could something like this (not tested):

@TestFor(AbcController)
@Mock([Abc])
class AbcControllerSpec extends Specification {
  void 'Test action catch block'() {
    setup:
      this.metaClass.println = { Object value ->
         throw new DataIntegrityViolationException()
      }
    and:
      params.id = 1
    when:
      controller.tst()
    then:
      DataIntegrityViolationException dive = thrown()
  }
}

Answer 2

If you are testing DataIntegrityViolationException it means you must be inserting and updating some record in the try block.

To test catch block you need a test case which violates one of the DB constraints while inserting or updating the record.

For eg inserting record with duplicate primary key.