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kotlinlang

test
```
class WeatherPresenterTest : Spek ({
	given("a weather presenter") {
		val repository 	= mock&lt;WeatherRepository&gt;()
		val view		= mock&lt;WeatherView&gt;()

		val presenter 	= WeatherPresenter(repository)

		beforeEachTest {
			presenter.attachView(view)
		}

		whenever("fetch weather") {
			then("return success") {
				repository.fetchWeather() willReturnSingle weatherData // this weatherData from fixture
				
				presenter.fetchWeather()

				verify(view).onLoadWeatherSuccess(weatherData)
				verifyNoMoreInteraction(view)
			}

			then("return error") {
				repository.fetchWeather() willReturnSingleError weatherDataError // this weatherData from fixture
				
				presenter.fetchWeather()

				verify(view).onLoadWeatherError(weatherDataError)
				verifyNoMoreInteraction(view)
			}
		}

		afterEachTest {
			presenter.detachView()
		}
	}
})
```