Programming Groovy 2

18.9 Mocking Using Map

We saw an example of using ​Expando​ as a mock object. We can also use a ​Map​. A map, as we know, has keys and associated values. The values can be objects or even closures. We can take advantage of this to use a ​Map​ in place of a collaborator.

Here’s a rewrite of the example using ​Expando​ from Section 18.8, ​Mocking Using Expando​, this time using a ​Map​:

import com.agiledeveloper.ClassWithDependency

class TestUsingMap extends GroovyTestCase {
  void testMethodA() {
    def text = ''
    def fileMock = [write : { text = it }]

    def testObj = new ClassWithDependency()
    testObj.methodA(1, fileMock)

    assertEquals "The value is 1.", text
  }
}