Bug 463728: [1.8][compiler][inference] Ternary operator in lambda

derives wrong type

Change-Id: I437fe9955a5bec0be699a66f0fc6a68b4a94f1fd

2 files changed, 43 insertions, 8 deletions

diff --git a/org.eclipse.jdt.core.tests.compiler/src/org/eclipse/jdt/core/tests/compiler/regression/GenericsRegressionTest_1_8.java b/org.eclipse.jdt.core.tests.compiler/src/org/eclipse/jdt/core/tests/compiler/regression/GenericsRegressionTest_1_8.java
index d55606d9b3..99e352b19d 100644
--- a/org.eclipse.jdt.core.tests.compiler/src/org/eclipse/jdt/core/tests/compiler/regression/GenericsRegressionTest_1_8.java
+++ b/org.eclipse.jdt.core.tests.compiler/src/org/eclipse/jdt/core/tests/compiler/regression/GenericsRegressionTest_1_8.java
@@ -5228,4 +5228,40 @@ public void testBug445231() {
 	"not anon\n" +
 	"Ok", null);
 }
+public void testBug463728() {
+	runConformTest(
+		new String[] {
+			"Main.java",
+			"import java.util.function.Function;\n" + 
+			"\n" + 
+			"\n" + 
+			"class Color {\n" + 
+			"	\n" + 
+			"}\n" + 
+			"\n" + 
+			"class TypeMapper<R> {\n" + 
+			"\n" + 
+			"	public TypeMapper() {\n" + 
+			"	}\n" + 
+			"	public R orElse(R result) {\n" + 
+			"		return result;\n" + 
+			"	}\n" + 
+			"}\n" + 
+			"\n" + 
+			"public class Main {\n" + 
+			"	Color A;\n" + 
+			"	Color B;\n" + 
+			"\n" + 
+			"	public static <T, R> TypeMapper<R> mapType(Function<T, R> mapper) {\n" + 
+			"		return new TypeMapper<R>();\n" + 
+			"	}\n" + 
+			"\n" + 
+			"	public Color getForeground(Object element) {\n" + 
+			"		return mapType(library -> {\n" + 
+			"				return (element != null ? A : B);\n" + 
+			"			}).orElse(null);\n" + 
+			"	}\n" + 
+			"}\n"
+		});
+}
 }
diff --git a/org.eclipse.jdt.core/compiler/org/eclipse/jdt/internal/compiler/ast/LambdaExpression.java b/org.eclipse.jdt.core/compiler/org/eclipse/jdt/internal/compiler/ast/LambdaExpression.java
index 8fc1d41a59..877114a78c 100644
--- a/org.eclipse.jdt.core/compiler/org/eclipse/jdt/internal/compiler/ast/LambdaExpression.java
+++ b/org.eclipse.jdt.core/compiler/org/eclipse/jdt/internal/compiler/ast/LambdaExpression.java
@@ -1,5 +1,5 @@
 /*******************************************************************************
- * Copyright (c) 2012, 2014 IBM Corporation and others.
+ * Copyright (c) 2012, 2015 IBM Corporation and others.
  * All rights reserved. This program and the accompanying materials
  * are made available under the terms of the Eclipse Public License v1.0
  * which accompanies this distribution, and is available at
@@ -36,6 +36,7 @@
  *							Bug 452788 - [1.8][compiler] Type not correctly inferred in lambda expression
  *							Bug 453483 - [compiler][null][loop] Improve null analysis for loops
  *							Bug 455723 - Nonnull argument not correctly inferred in loop
+ *							Bug 463728 - [1.8][compiler][inference] Ternary operator in lambda derives wrong type
  *     Andy Clement (GoPivotal, Inc) aclement@gopivotal.com - Contributions for
  *                          Bug 405104 - [1.8][compiler][codegen] Implement support for serializeable lambdas
  *******************************************************************************/
@@ -981,13 +982,11 @@ public class LambdaExpression extends FunctionalExpression implements IPolyExpre
 			this.returnsValue = true;
 			this.voidCompatible = false;
 			this.valueCompatible = !this.returnsVoid;
-			if (resultType != null) {
-				Expression [] returnExpressions = this.resultExpressions;
-				int resultsLength = returnExpressions.length;
-				System.arraycopy(returnExpressions, 0, returnExpressions = new Expression[resultsLength + 1], 0, resultsLength);
-				returnExpressions[resultsLength] = expression;
-				this.resultExpressions = returnExpressions;
-			}
+			Expression [] returnExpressions = this.resultExpressions;
+			int resultsLength = returnExpressions.length;
+			System.arraycopy(returnExpressions, 0, returnExpressions = new Expression[resultsLength + 1], 0, resultsLength);
+			returnExpressions[resultsLength] = expression;
+			this.resultExpressions = returnExpressions;
 		} else {
 			this.returnsVoid = true;
 			this.valueCompatible = false;