Franklin Dattein

If you are wondering how to mock the localizaton provider in a Grails Controller, these are two example on how to do it.

The first one  (FooController) is used when you want to have an instance of MessageSource injected as a member of your controller.

class FooController {
  def messageSource

  def index = {
    def someMessage = messageSource.getMessage("some.key")
    log.debug("Localized message: " + someMessage)
    render(someMessage)
  }
}

And its test class:

class FooControllerTests extends ControllerUnitTestCase {
  void testIndex() {
    //controller.messageSource = [getMessage: { def key, def locale -> return key }]
    controller.messageSource = [getMessage: { def key -> return key }] //returns the input key
    controller.index()
    assertEquals "Should return a localized key", "some.key", controller.response.contentAsString
  }
}

The second one (BarController) is when you prefer to use the “message” closure:

class BarController {
  def index = {
    def someMessage = message(code: "some.key", default: "Some default message")
    log.debug("Localized message: " + someMessage)
    render(someMessage)
  }
}

Finally, how to mock it:

class FooControllerTests extends ControllerUnitTestCase {
  void testIndex() {
    //controller.messageSource = [getMessage: { def key, def locale -> return key }]
    controller.messageSource = [getMessage: { def key -> return key }] //returns the input key
    controller.index()
    assertEquals "Should return a localized key", "some.key", controller.response.contentAsString
  }
}

Quick and simple. I hope you enjoy these simple and useful examples.