mockito-kotlin で lambda を mock + @RunWith(AndroidJUnit4::class) のときは work around が必要

以下のような @RunWith(AndroidJUnit4::class) を使わない Unit Test は問題なく動くのですが、 class HogeTest { @Test fun test() { val listener = mock<(Boolean) -> Unit>() ... verify(listener)(false) } } 次のように @RunWith(AndroidJUnit4::class) をつけるとエラーが発生します。 @RunWith(AndroidJUnit4::class) class HogeTest { @Test fun test() { val listener = mock<(Boolean) -> Unit>() ... verify(listener)(false) } }
org.mockito.exceptions.base.MockitoException:
ClassCastException occurred while creating the mockito mock :
class to mock : 'kotlin.jvm.functions.Function1', loaded by classloader : 'sun.misc.Launcher$AppClassLoader@18b4aac2'
created class : 'kotlin.jvm.functions.Function1$MockitoMock$1350680399', loaded by classloader : 'net.bytebuddy.dynamic.loading.MultipleParentClassLoader@7a2a2c83'
proxy instance class : 'kotlin.jvm.functions.Function1$MockitoMock$1350680399', loaded by classloader : 'net.bytebuddy.dynamic.loading.MultipleParentClassLoader@7a2a2c83'
instance creation by : ObjenesisInstantiator


この場合クッションになる interface を定義すると動きます。 @RunWith(AndroidJUnit4::class) class HogeTest { private interface Callback : (Boolean) -> Unit @Test fun test() { val listener = mock<Callback>() ... verify(listener)(false) } }

参考 : https://github.com/nhaarman/mockito-kotlin/issues/272