Checking that a List is not empty in Hamcrest

Ian Dallas picture Ian Dallas · Sep 2, 2010 · Viewed 117.7k times · Source

I was wondering if anyone knew of a way to check if a List is empty using assertThat() and Matchers?

Best way I could see just use JUnit:

assertFalse(list.isEmpty());

But I was hoping that there was some way to do this in Hamcrest.

Answer

skaffman picture skaffman · Sep 2, 2010

Well there's always

assertThat(list.isEmpty(), is(false));

... but I'm guessing that's not quite what you meant :)

Alternatively:

assertThat((Collection)list, is(not(empty())));

empty() is a static in the Matchers class. Note the need to cast the list to Collection, thanks to Hamcrest 1.2's wonky generics.

The following imports can be used with hamcrest 1.3

import static org.hamcrest.Matchers.empty;
import static org.hamcrest.core.Is.is;
import static org.hamcrest.core.IsNot.*;