package org.junit.internal.matchers;
   
   import org.junit.Test;
   
   import static org.hamcrest.CoreMatchers.is;
   import static org.junit.Assert.assertThat;
   import static org.junit.internal.matchers.ThrowableCauseMatcher.hasCause;
   
   public class ThrowableCauseMatcherTest {
  
      @Test
      public void shouldAllowCauseOfDifferentClassFromRoot() throws Exception {
          NullPointerException expectedCause = new NullPointerException("expected");
          Exception actual = new Exception(expectedCause);
  
          assertThat(actual, hasCause(is(expectedCause)));
      }
  }