DATACMNS-963 - Returned type returns distinct input properties now.

We now manually filter already gathered property names in ReturnedInterface.getInputProperties() as we have to deal with duplications for properties with the same name at different levels of the inheritance hierarchy.

Author: odrotbohm

src/main/java/org/springframework/data/repository/query/ReturnedType.java

@@ -191,7 +191,9 @@ public List<String> getInputProperties() {
 			List<String> properties = new ArrayList<String>();
 
 			for (PropertyDescriptor descriptor : information.getInputProperties()) {
-				properties.add(descriptor.getName());
+				if (!properties.contains(descriptor.getName())) {
+					properties.add(descriptor.getName());
+				}
 			}
 
 			return properties;

src/test/java/org/springframework/data/repository/query/ReturnedTypeUnitTests.java

@@ -179,6 +179,20 @@ public void considersInterfaceImplementedByDomainTypeNotProjecting() throws Exce
 		assertThat(type.isProjecting(), is(false));
 	}
 
+	/**
+	 * @see DATACMNS-963
+	 */
+	@Test
+	public void detectsDistinctInputProperties() {
+
+		ReturnedType type = ReturnedType.of(Child.class, Object.class, new SpelAwareProxyProjectionFactory());
+
+		List<String> properties = type.getInputProperties();
+
+		assertThat(properties, hasSize(1));
+		assertThat(properties, contains("firstname"));
+	}
+
 	private static ReturnedType getReturnedType(String methodName, Class<?>... parameters) throws Exception {
 		return getQueryMethod(methodName, parameters).getResultProcessor().getReturnedType();
 	}
@@ -262,4 +276,12 @@ interface OpenProjection {
 		@Value("#{target.firstname + ' ' + target.lastname}")
 		String getFullName();
 	}
+
+	static interface Parent {
+		String getFirstname();
+	}
+
+	static interface Child extends Parent {
+		String getFirstname();
+	}
 }