Improved the naming of error values in the case where they're java enums, since those already have meaningful names we can use.

Author: pimterry

src/main/java/org/junit/experimental/theories/PotentialAssignment.java

@@ -18,9 +18,12 @@ public String toString() {
             }
 
             @Override
-            public String getDescription()
-                    throws CouldNotGenerateValueException {
-                return name;
+            public String getDescription() throws CouldNotGenerateValueException {
+            	if (value.getClass().isEnum()) {
+            		return value.toString();
+            	} else {
+            		return name;
+            	}
             }
         };
     }

src/test/java/org/junit/tests/experimental/theories/EnumDatapointNamesTest.java

@@ -0,0 +1,84 @@
+package org.junit.tests.experimental.theories;
+
+import static org.hamcrest.CoreMatchers.*;
+import org.junit.Assert;
+import org.junit.Test;
+import org.junit.experimental.theories.DataPoint;
+import org.junit.experimental.theories.DataPoints;
+import org.junit.experimental.theories.Theories;
+import org.junit.experimental.theories.Theory;
+import org.junit.runner.JUnitCore;
+import org.junit.runner.Request;
+import org.junit.runner.Result;
+import org.junit.runner.Runner;
+import org.junit.runners.model.InitializationError;
+
+public class EnumDatapointNamesTest {
+	
+	@Test
+	public void enumErrorsUseEnumNameWithSingleValues() throws InitializationError {
+		Result result = runTheoryTest(EnumTestWithBadValue.class);
+		
+		Assert.assertEquals(1, result.getFailureCount());
+		
+		Throwable ex = result.getFailures().get(0).getException();
+		Assert.assertThat(ex.getMessage(), containsString(EnumValue.BAD_VALUE.toString()));
+		return;
+	}
+	
+	@Test
+	public void enumErrorsUseEnumNameWithArrays() throws InitializationError {
+		Result result = runTheoryTest(EnumTestWithBadValueInArray.class);
+		
+		Assert.assertEquals(1, result.getFailureCount());
+		
+		Throwable ex = result.getFailures().get(0).getException();
+		Assert.assertThat(ex.getMessage(), containsString(EnumValue.BAD_VALUE.toString()));
+		return;
+	}	
+	
+	private Result runTheoryTest(Class<?> testClass) throws InitializationError {
+		JUnitCore junitRunner = new JUnitCore();
+		Runner theoryRunner = new Theories(testClass);
+		Request request = Request.runner(theoryRunner);
+		return junitRunner.run(request);
+	}
+	
+    private enum EnumValue {
+        ONE_VALUE, BAD_VALUE, ANOTHER_VALUE 
+    }
+    
+    private static void methodUnderTest(EnumValue param) {
+        if (param == EnumValue.BAD_VALUE) {
+            throw new IllegalArgumentException("Bad param");
+        }
+    }
+	
+	public static class EnumTestWithBadValue {
+		
+	    @DataPoint
+	    public static EnumValue oneValue = EnumValue.ONE_VALUE;
+	    
+	    @DataPoint 
+	    public static EnumValue badValue = EnumValue.BAD_VALUE;
+	
+	    @Theory
+	    public void theoryTest(EnumValue param) {
+	    	methodUnderTest(param);
+	    }
+	    
+	}	
+	
+	public static class EnumTestWithBadValueInArray {
+	
+	    @DataPoints
+	    public static EnumValue[] allValues = EnumValue.values();
+	
+	    @Theory
+	    public void theoryTest(EnumValue param) {
+	    	methodUnderTest(param);
+	    }
+	    
+	}
+
+}