package org.junit.internal.matchers;
   
   import static org.hamcrest.CoreMatchers.any;
   import static org.hamcrest.CoreMatchers.containsString;
   import static org.hamcrest.CoreMatchers.equalTo;
   import static org.hamcrest.CoreMatchers.notNullValue;
   import static org.junit.Assert.assertFalse;
   import static org.junit.Assert.assertThat;
   import static org.junit.Assert.assertTrue;
  import static org.junit.internal.matchers.StacktracePrintingMatcher.isException;
  import static org.junit.internal.matchers.StacktracePrintingMatcher.isThrowable;
  
  import org.junit.Test;
  
  public class StacktracePrintingMatcherTest {
  
      @Test
      public void succeedsWhenInnerMatcherSucceeds() throws Exception {
          assertTrue(isThrowable(any(Throwable.class)).matches(new Exception()));
      }
  
      @Test
      public void failsWhenInnerMatcherFails() throws Exception {
          assertFalse(isException(notNullValue(Exception.class)).matches(null));
      }
  
      @Test
      public void assertThatIncludesStacktrace() {
          Exception actual = new IllegalArgumentException("my message");
          Exception expected = new NullPointerException();
  
          try {
              assertThat(actual, isThrowable(equalTo(expected)));
          } catch (AssertionError e) {
              assertThat(e.getMessage(), containsString("Stacktrace was: java.lang.IllegalArgumentException: my message"));
          }
      }
  }