package org.junit.tests.validation;
   
   import static org.junit.Assert.assertEquals;
   
   import org.junit.Before;
   import org.junit.Test;
   import org.junit.internal.runners.JUnit4ClassRunner;
   import org.junit.runner.JUnitCore;
   import org.junit.runner.Result;
  import org.junit.runner.RunWith;
  import org.junit.runner.notification.Failure;
  
  @SuppressWarnings("deprecation")
  public class BadlyFormedClassesTest {
      public static class FaultyConstructor {
          public FaultyConstructor() throws Exception {
              throw new Exception("Thrown during construction");
          }
  
          @Test
          public void someTest() {
              /*
                  * Empty test just to fool JUnit and IDEs into running this class as
                  * a JUnit test
                  */
          }
      }
  
      ;
  
      @RunWith(JUnit4ClassRunner.class)
      public static class BadBeforeMethodWithLegacyRunner {
          @Before
          void before() {
  
          }
  
          @Test
          public void someTest() {
          }
      }
  
      ;
  
      public static class NoTests {
          // class without tests
      }
  
      @Test
      public void constructorException() {
          String message = exceptionMessageFrom(FaultyConstructor.class);
          assertEquals("Thrown during construction", message);
      }
  
      @Test
      public void noRunnableMethods() {
          assertEquals("No runnable methods", exceptionMessageFrom(NoTests.class));
      }
  
      @Test
      public void badBeforeMethodWithLegacyRunner() {
          assertEquals("Method before should be public",
                  exceptionMessageFrom(BadBeforeMethodWithLegacyRunner.class));
      }
  
      private String exceptionMessageFrom(Class<?> testClass) {
          JUnitCore core = new JUnitCore();
          Result result = core.run(testClass);
          Failure failure = result.getFailures().get(0);
          String message = failure.getException().getMessage();
          return message;
      }
  }