From 37f78a37074c4f363f19bf3005a105a92c4b44f9 Mon Sep 17 00:00:00 2001
From: Oliver Gierke <ogierke@pivotal.io>
Date: Tue, 4 Apr 2017 07:07:42 +0200
Subject: [PATCH] DATACMNS-1024 - Reinstated root object method lookup behavior
 in EvaluationContextExtensionInformation.
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The switch to Java 8 and thus to Collectors.toMap(…) to assemble the root object's methods as functions broke due to the fact that overloaded methods have the same name which causes a collision in keys when preparing the map of functions.

We now use the same approach as before, of letting later methods trump earlier ones as this fixes the original bug. Filed DATACMNS-1026 to keep track of that problem.

Related tickets: DATACMNS-1026.
---
 ...EvaluationContextExtensionInformation.java |  3 +-
 ...nContextExtensionInformationUnitTests.java | 53 +++++++++++++++++++
 2 files changed, 55 insertions(+), 1 deletion(-)
 create mode 100644 src/test/java/org/springframework/data/repository/query/EvaluationContextExtensionInformationUnitTests.java

diff --git a/src/main/java/org/springframework/data/repository/query/EvaluationContextExtensionInformation.java b/src/main/java/org/springframework/data/repository/query/EvaluationContextExtensionInformation.java
index a84b97a66..7ff54876b 100644
--- a/src/main/java/org/springframework/data/repository/query/EvaluationContextExtensionInformation.java
+++ b/src/main/java/org/springframework/data/repository/query/EvaluationContextExtensionInformation.java
@@ -250,7 +250,8 @@ class EvaluationContextExtensionInformation {
 			return target.map(it -> methods.stream()//
 					.collect(Collectors.toMap(//
 							Method::getName, //
-							method -> new Function(method, it))))
+							method -> new Function(method, it), //
+							(left, right) -> right)))
 					.orElseGet(Collections::emptyMap);
 		}
 
diff --git a/src/test/java/org/springframework/data/repository/query/EvaluationContextExtensionInformationUnitTests.java b/src/test/java/org/springframework/data/repository/query/EvaluationContextExtensionInformationUnitTests.java
new file mode 100644
index 000000000..0c912ef6c
--- /dev/null
+++ b/src/test/java/org/springframework/data/repository/query/EvaluationContextExtensionInformationUnitTests.java
@@ -0,0 +1,53 @@
+/*
+ * Copyright 2017 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.springframework.data.repository.query;
+
+import java.util.Optional;
+
+import org.junit.Test;
+import org.springframework.data.repository.query.spi.EvaluationContextExtension;
+
+/**
+ * Unit tests for {@link EvaluationContextExtensionInformation}.
+ * 
+ * @author Oliver Gierke
+ */
+public class EvaluationContextExtensionInformationUnitTests {
+
+	@Test // DATACMNS-1024
+	public void supportsMethodOverloadsOnRoot() {
+
+		EvaluationContextExtensionInformation information = new EvaluationContextExtensionInformation(
+				SampleExtension.class);
+
+		Optional<Object> target = Optional.of(new Object());
+
+		information.getRootObjectInformation(target).getFunctions(target);
+	}
+
+	interface SampleExtension extends EvaluationContextExtension {
+
+		@Override
+		SampleRoot getRootObject();
+	}
+
+	interface SampleRoot {
+
+		void someMethod();
+
+		void someMethod(String parameter);
+	}
+}