Triple AAA (Arrange-Act-Assert)

UserEmailStepViewModelTest.kt

@Test
fun `user email - already exists a user email`() {
    // arrange
    every { localRepository.userEmail() }.returns("[email protected]")
    val viewModel = UserEmailStepViewModel(localRepository)

    // act
    val result = viewModel.userEmail

    // assert
    Truth.assertThat(result).isEqualTo("[email protected]")
}