Hey,
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.
Thanks!
views:
118answers:
3
+2
A:
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's wonky generics.
skaffman
2010-09-02 20:47:26
I find that Hamcrest code looks much nicer if you change your syntax highlighting to make the parenthesis invisible...
skaffman
2010-09-02 20:53:32
Your second assertThat() gives me the following error: The method assertThat(T, Matcher<T>) in the type Assert is not applicable for the arguments (List<Integer>, Matcher<Collection<Object>>)
tkeE2036
2010-09-02 21:12:53
@tkeE2036: That's Hamcrest's broken generics at work. Sometimes you need to cast to make it compile, e.g. `assertThat((Collection)list, is(not(empty())));`
skaffman
2010-09-02 21:46:04
A:
Use IsEmptyCollection.empty() matcher. Here is hamcrests unit tests using this. Specifically:
List list = new ArrayList();
assertMatches("empty collection", empty(), list);
krock
2010-09-02 20:48:31
A:
For a better solution, vote for: http://code.google.com/p/hamcrest/issues/detail?id=97
Fabricio Lemos
2010-10-02 15:40:18