@Test(expected = NullPointerException.class)
public void shouldThrowNullPointerExceptionIfNullMapperPassedToMapFirst() throws Exception {
// Given
Triple<Integer, String, Boolean> triple = tuple(5, "Five", true);
Mapper<Integer, String> mapper = null;
// When
triple.mapFirst(mapper);
// Then a NullPointerException is thrown
}
@Test(expected = NullPointerException.class)
public void shouldThrowNullPointerExceptionIfNullUnaryFunctionPassedToMapFirst()
throws Exception {
// Given
Triple<Integer, String, Boolean> triple = tuple(5, "Five", true);
UnaryFunction<Integer, String> function = null;
// When
triple.mapFirst(function);
// Then a NullPointerException is thrown
}
@Test
public void shouldBeMappableUsingUnaryFunctionOnFirstPosition() throws Exception {
// Given
Triple<Integer, String, Boolean> triple = tuple(5, "Five", true);
UnaryFunction<Integer, String> function =
new UnaryFunction<Integer, String>() {
@Override
public String call(Integer input) {
return String.valueOf(input);
}
};
Triple<String, String, Boolean> expected = tuple("5", "Five", true);
// When
Triple<String, String, Boolean> actual = triple.mapFirst(function);
// Then
assertThat(actual, is(expected));
}