[Enhanced Switch] Problem with switch and enums - incorrect duplicate

case error * Fixes eclipse-jdt#3344
srikanth-sankaran · Nov 25, 2024 · 32b09fd · 32b09fd
1 parent 2363e0f
commit 32b09fd
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Showing 2 changed files with 87 additions and 8 deletions.
diff --git a/...ipse.jdt.core.compiler.batch/src/org/eclipse/jdt/internal/compiler/ast/CaseStatement.java b/...ipse.jdt.core.compiler.batch/src/org/eclipse/jdt/internal/compiler/ast/CaseStatement.java
@@ -99,7 +99,7 @@ public String toString() {
 }
 
 private boolean essentiallyQualifiedEnumerator(Expression e, TypeBinding selectorType) { // "Essentially" as in not "superfluously" qualified.
-	return e instanceof QualifiedNameReference qnr && qnr.binding instanceof FieldBinding field
+	return e instanceof NameReference reference && reference.binding instanceof FieldBinding field
 				&& (field.modifiers & ClassFileConstants.AccEnum) != 0 && !TypeBinding.equalsEquals(e.resolvedType, selectorType); // <<-- essential qualification
 }
 
@@ -135,13 +135,12 @@ private Constant resolveConstantLabel(BlockScope scope, TypeBinding caseType, Ty
 		if (expression instanceof NameReference reference && reference.binding instanceof FieldBinding field) {
 			if ((field.modifiers & ClassFileConstants.AccEnum) == 0)
 				 scope.problemReporter().enumSwitchCannotTargetField(reference, field);
-			else if (reference instanceof QualifiedNameReference) {
-				if (options.complianceLevel < ClassFileConstants.JDK21)
-					scope.problemReporter().cannotUseQualifiedEnumConstantInCaseLabel(reference, field);
-				else if (!TypeBinding.equalsEquals(caseType, selectorType)) {
-					this.swich.switchBits |= SwitchStatement.QualifiedEnum;
-					return StringConstant.fromValue(CharOperation.toString(reference.getName()));
-				}
+			else if (reference instanceof QualifiedNameReference && options.complianceLevel < ClassFileConstants.JDK21)
+				scope.problemReporter().cannotUseQualifiedEnumConstantInCaseLabel(reference, field);
+
+			if (!TypeBinding.equalsEquals(caseType, selectorType)) {
+				this.swich.switchBits |= SwitchStatement.QualifiedEnum;
+				return StringConstant.fromValue(CharOperation.toString(reference.getName()));
 			}
 			return IntConstant.fromValue(field.original().id + 1); // (ordinal value + 1) zero should not be returned see bug 141810
 		}

diff --git a/....tests.compiler/src/org/eclipse/jdt/core/tests/compiler/regression/SwitchPatternTest.java b/....tests.compiler/src/org/eclipse/jdt/core/tests/compiler/regression/SwitchPatternTest.java
@@ -9507,4 +9507,84 @@ public static void main(String[] args) {
 				},
 				"Default");
 	}
+
+	// https://github.com/eclipse-jdt/eclipse.jdt.core/issues/3344
+	// [Enhanced Switch] Problem with switch and enums - incorrect duplicate case error
+	public void testIssue3344() {
+		runConformTest(
+				new String[] {
+						"Main.java",
+						"""
+						import static p.A.A1;
+						import static p.A.A2;
+						import static p.B.B1;
+						import static p.B.B2;
+
+						import java.util.Arrays;
+						import java.util.stream.Stream;
+
+						import p.X;
+						import p.A;
+						import p.B;
+
+						public class Main {
+
+							public static void main(String[] args) {
+								Stream.concat(Arrays.stream(A.values()), Arrays.stream(B.values())).forEach(
+									x -> { System.out.printf("%s -> %s, %s\\n", x, bad_switch(x), good_switch(x)); }
+								);
+							}
+
+						    static String bad_switch(X x) {
+						        return switch (x) {
+						            case A1 -> "A1";
+						            case A2 -> "A2";
+						            case B1 -> "B1";
+						            case B2 -> "B2";
+						            default -> "unknown";
+						        };
+						    }
+
+						    static String good_switch(X x) {
+						        return switch (x) {
+						            case A.A1 -> "A1";
+						            case A.A2 -> "A2";
+						            case B.B1 -> "B1";
+						            case B.B2 -> "B2";
+						            default -> "unknown";
+						        };
+						    }
+						}
+						""",
+						"p/A.java",
+						"""
+						package p;
+
+						public enum A implements X {
+							A1,
+							A2,
+						}
+						""",
+						"p/B.java",
+						"""
+						package p;
+
+						public enum B implements X {
+							B1,
+							B2
+						}
+						""",
+						"p/X.java",
+						"""
+						package p;
+
+						public interface X {
+						}
+						"""
+				},
+				"A1 -> A1, A1\n" +
+				"A2 -> A2, A2\n" +
+				"B1 -> B1, B1\n" +
+				"B2 -> B2, B2");
+	}
 }