Bug 576861 - Internal compiler error when switch expression returns aI20211101-1800I20211031-1800I20211030-1800I20211029-1800

functional interface

Change-Id: Ia88420f808bf5a164a4a8af24b0ecfcd68348ae9
Signed-off-by: Manoj Palat <manpalat@in.ibm.com>
Reviewed-on: https://git.eclipse.org/r/c/jdt/eclipse.jdt.core/+/187077

3 files changed, 30 insertions, 2 deletions

diff --git a/org.eclipse.jdt.core.tests.compiler/src/org/eclipse/jdt/core/tests/compiler/regression/SwitchExpressionsYieldTest.java b/org.eclipse.jdt.core.tests.compiler/src/org/eclipse/jdt/core/tests/compiler/regression/SwitchExpressionsYieldTest.java
index 9bfd9e196b..eb15476e8b 100644
--- a/org.eclipse.jdt.core.tests.compiler/src/org/eclipse/jdt/core/tests/compiler/regression/SwitchExpressionsYieldTest.java
+++ b/org.eclipse.jdt.core.tests.compiler/src/org/eclipse/jdt/core/tests/compiler/regression/SwitchExpressionsYieldTest.java
@@ -6115,4 +6115,25 @@ public class SwitchExpressionsYieldTest extends AbstractRegressionTest {
 				},
 				"Success");
 	}
+	public void testBug576861_001() {
+		this.runConformTest(
+				new String[] {
+				"X.java",
+				"import java.util.Comparator;\n"+
+				"\n"+
+				"public class X {\n"+
+				" public static void foo(Comparator<? super Long> comparator) {}\n"+
+				"\n"+
+				" public static void main(String[] args) {\n"+
+				"   int someSwitchCondition = 10;\n"+
+				"   X.foo(switch (someSwitchCondition) {\n"+
+				"   case 10 -> Comparator.comparingLong(Long::longValue);\n"+
+				"   default -> throw new IllegalArgumentException(\"Unsupported\");\n"+
+				" });\n"+
+				"   System.out.println(\"hello\");\n"+
+				" }\n"+
+				"}"
+				},
+				"hello");
+	}
 }
diff --git a/org.eclipse.jdt.core/compiler/org/eclipse/jdt/internal/compiler/ast/SwitchExpression.java b/org.eclipse.jdt.core/compiler/org/eclipse/jdt/internal/compiler/ast/SwitchExpression.java
index 806abac23c..f9801a9fa1 100644
--- a/org.eclipse.jdt.core/compiler/org/eclipse/jdt/internal/compiler/ast/SwitchExpression.java
+++ b/org.eclipse.jdt.core/compiler/org/eclipse/jdt/internal/compiler/ast/SwitchExpression.java
@@ -53,6 +53,8 @@ public class SwitchExpression extends SwitchStatement implements IPolyExpression
 	private boolean isPolyExpression = false;
 	private TypeBinding[] originalValueResultExpressionTypes;
 	private TypeBinding[] finalValueResultExpressionTypes;
+	/* package */ Map<Expression, TypeBinding> originalTypeMap;
+
 
 	private int nullStatus = FlowInfo.UNKNOWN;
 	public List<Expression> resultExpressions;
@@ -473,6 +475,8 @@ public class SwitchExpression extends SwitchStatement implements IPolyExpression
 					}
 				}
 
+				if (this.originalTypeMap == null)
+					this.originalTypeMap = new HashMap<>();
 				resolve(upperScope);
 
 				if (this.statements == null || this.statements.length == 0) {
@@ -512,7 +516,8 @@ public class SwitchExpression extends SwitchStatement implements IPolyExpression
 					return this.resolvedType = null; // error flagging would have been done during the earlier phase.
 				for (int i = 0; i < resultExpressionsCount; i++) {
 					Expression resultExpr = this.resultExpressions.get(i);
-					if (resultExpr.resolvedType == null || resultExpr.resolvedType.kind() == Binding.POLY_TYPE) {
+					TypeBinding origType = this.originalTypeMap.get(resultExpr);
+					if (origType == null || origType.kind() == Binding.POLY_TYPE) {
 						this.finalValueResultExpressionTypes[i] = this.originalValueResultExpressionTypes[i] =
 							resultExpr.resolveTypeExpecting(upperScope, this.expectedType);
 					}
diff --git a/org.eclipse.jdt.core/compiler/org/eclipse/jdt/internal/compiler/ast/YieldStatement.java b/org.eclipse.jdt.core/compiler/org/eclipse/jdt/internal/compiler/ast/YieldStatement.java
index f626942837..e750fd539a 100644
--- a/org.eclipse.jdt.core/compiler/org/eclipse/jdt/internal/compiler/ast/YieldStatement.java
+++ b/org.eclipse.jdt.core/compiler/org/eclipse/jdt/internal/compiler/ast/YieldStatement.java
@@ -245,7 +245,9 @@ public void resolve(BlockScope skope) {
 			this.scope.problemReporter().switchExpressionsYieldOutsideSwitchExpression(this);
 		}
 	}
-	this.expression.resolveType(this.scope);
+	TypeBinding type = this.expression.resolveType(this.scope);
+	if (this.switchExpression != null && type != null)
+		this.switchExpression.originalTypeMap.put(this.expression, type);
 }
 
 @Override