ConvertServiceTest: add null tests

Ensure the null converter is behaving as intended.

Author: hinerm

src/test/java/org/scijava/convert/ConvertServiceTest.java

@@ -78,6 +78,37 @@ public void tearDown() {
 		convertService.getContext().dispose();
 	}
 
+	@Test
+	public void testNull() {
+		// Test convertService.supports for null parameters
+		assertTrue(convertService.supports((Object)null, Object.class));
+		assertTrue(convertService.supports((Class<Object>)null, Object.class));
+		assertTrue(convertService.supports(Object.class, (Class<Object>)null));
+		assertTrue(convertService.supports(Object.class, (Type)null));
+		assertTrue(convertService.supports(new Object(), (Class<Object>)null));
+		assertTrue(convertService.supports(new Object(), (Type)null));
+		assertTrue(convertService.supports(new ConversionRequest((Object)null, Object.class)));
+		assertTrue(convertService.supports(new ConversionRequest((Class<Object>)null, Object.class)));
+		assertTrue(convertService.supports(new ConversionRequest(Object.class, (Class<Object>)null)));
+		assertTrue(convertService.supports(new ConversionRequest(Object.class, (Type)null)));
+		assertTrue(convertService.supports(new ConversionRequest(new Object(), (Class<Object>)null)));
+		assertTrue(convertService.supports(new ConversionRequest(new Object(), (Type)null)));
+
+		// Test convertService.convert for null parameters
+		assertNull(convertService.convert((Object)null, Object.class));
+		assertNull(convertService.convert((Class<Object>)null, Object.class));
+		assertNull(convertService.convert(Object.class, (Class<Object>)null));
+		assertNull(convertService.convert(Object.class, (Type)null));
+		assertNull(convertService.convert(new Object(), (Class<Object>)null));
+		assertNull(convertService.convert(new Object(), (Type)null));
+		assertNull(convertService.convert(new ConversionRequest((Object)null, Object.class)));
+		assertNull(convertService.convert(new ConversionRequest((Class<Object>)null, Object.class)));
+		assertNull(convertService.convert(new ConversionRequest(Object.class, (Class<Object>)null)));
+		assertNull(convertService.convert(new ConversionRequest(Object.class, (Type)null)));
+		assertNull(convertService.convert(new ConversionRequest(new Object(), (Class<Object>)null)));
+		assertNull(convertService.convert(new ConversionRequest(new Object(), (Type)null)));
+	}
+
 	/** Tests {@link ConvertService#supports(Class, Class)}. */
 	@Test
 	public void testCanConvert() {