SimpleAliasRegistry.hasAlias properly resolves multiple chained aliases

Issue: SPR-17191

(cherry picked from commit 2ac23ba)

Author: jhoeller

Diff for: spring-core/src/main/java/org/springframework/core/SimpleAliasRegistry.java

@@ -86,7 +86,9 @@ public boolean hasAlias(String name, String alias) {
 			String registeredName = entry.getValue();
 			if (registeredName.equals(name)) {
 				String registeredAlias = entry.getKey();
-				return (registeredAlias.equals(alias) || hasAlias(registeredAlias, alias));
+				if (registeredAlias.equals(alias) || hasAlias(registeredAlias, alias)) {
+					return true;
+				}
 			}
 		}
 		return false;

Diff for: spring-core/src/test/java/org/springframework/core/SimpleAliasRegistryTests.java

@@ -0,0 +1,63 @@
+/*
+ * Copyright 2002-2018 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.core;
+
+import org.junit.Test;
+
+import static org.junit.Assert.*;
+
+/**
+ * @author Juergen Hoeller
+ */
+public class SimpleAliasRegistryTests {
+
+	@Test
+	public void testAliasChaining() {
+		SimpleAliasRegistry registry = new SimpleAliasRegistry();
+		registry.registerAlias("test", "testAlias");
+		registry.registerAlias("testAlias", "testAlias2");
+		registry.registerAlias("testAlias2", "testAlias3");
+
+		assertTrue(registry.hasAlias("test", "testAlias"));
+		assertTrue(registry.hasAlias("test", "testAlias2"));
+		assertTrue(registry.hasAlias("test", "testAlias3"));
+		assertSame("test", registry.canonicalName("testAlias"));
+		assertSame("test", registry.canonicalName("testAlias2"));
+		assertSame("test", registry.canonicalName("testAlias3"));
+	}
+
+	@Test  // SPR-17191
+	public void testAliasChainingWithMultipleAliases() {
+		SimpleAliasRegistry registry = new SimpleAliasRegistry();
+		registry.registerAlias("name", "alias_a");
+		registry.registerAlias("name", "alias_b");
+		assertTrue(registry.hasAlias("name", "alias_a"));
+		assertTrue(registry.hasAlias("name", "alias_b"));
+
+		registry.registerAlias("real_name", "name");
+		assertTrue(registry.hasAlias("real_name", "name"));
+		assertTrue(registry.hasAlias("real_name", "alias_a"));
+		assertTrue(registry.hasAlias("real_name", "alias_b"));
+
+		registry.registerAlias("name", "alias_c");
+		assertTrue(registry.hasAlias("real_name", "name"));
+		assertTrue(registry.hasAlias("real_name", "alias_a"));
+		assertTrue(registry.hasAlias("real_name", "alias_b"));
+		assertTrue(registry.hasAlias("real_name", "alias_c"));
+	}
+
+}