From 2de63d4e1793075903792bd04006609c5be0d460 Mon Sep 17 00:00:00 2001
From: Stephan Herrmann <stephan.herrmann@berlin.de>
Date: Sun, 14 Jul 2024 20:17:20 +0200
Subject: [PATCH] Simplification / bugfix(?) + nobody ever expected the null
 returned from TypeBinding.actualType()

---
 .../internal/compiler/lookup/ReferenceBinding.java    |  7 ++++++-
 .../eclipse/jdt/internal/compiler/lookup/Scope.java   |  4 +---
 .../internal/compiler/lookup/SourceTypeBinding.java   | 11 ++++-------
 .../jdt/internal/compiler/lookup/TypeBinding.java     |  3 ++-
 4 files changed, 13 insertions(+), 12 deletions(-)

diff --git a/org.eclipse.jdt.core.compiler.batch/src/org/eclipse/jdt/internal/compiler/lookup/ReferenceBinding.java b/org.eclipse.jdt.core.compiler.batch/src/org/eclipse/jdt/internal/compiler/lookup/ReferenceBinding.java
index f6111791de2..4ccf2411878 100644
--- a/org.eclipse.jdt.core.compiler.batch/src/org/eclipse/jdt/internal/compiler/lookup/ReferenceBinding.java
+++ b/org.eclipse.jdt.core.compiler.batch/src/org/eclipse/jdt/internal/compiler/lookup/ReferenceBinding.java
@@ -330,7 +330,7 @@ public boolean canBeSeenBy(PackageBinding invocationPackage) {
 public boolean canBeSeenBy(ReferenceBinding receiverType, ReferenceBinding invocationType) {
 	if (isPublic()) return true;
 
-	if (isStatic() && (receiverType.isRawType() || receiverType.isParameterizedType()))
+	if (isStatic())
 		receiverType = receiverType.actualType(); // outer generics are irrelevant
 
 	if (TypeBinding.equalsEquals(invocationType, this) && TypeBinding.equalsEquals(invocationType, receiverType)) return true;
@@ -1063,6 +1063,11 @@ public final ReferenceBinding enclosingTypeAt(int relativeDepth) {
 	return current;
 }
 
+@Override
+public ReferenceBinding actualType() {
+	return this;
+}
+
 public int enumConstantCount() {
 	int count = 0;
 	FieldBinding[] fields = fields();
diff --git a/org.eclipse.jdt.core.compiler.batch/src/org/eclipse/jdt/internal/compiler/lookup/Scope.java b/org.eclipse.jdt.core.compiler.batch/src/org/eclipse/jdt/internal/compiler/lookup/Scope.java
index 750709cf20f..fb712686a41 100644
--- a/org.eclipse.jdt.core.compiler.batch/src/org/eclipse/jdt/internal/compiler/lookup/Scope.java
+++ b/org.eclipse.jdt.core.compiler.batch/src/org/eclipse/jdt/internal/compiler/lookup/Scope.java
@@ -5709,9 +5709,7 @@ public TypeBinding getMatchingUninitializedType(TypeBinding targetClass, boolean
 			SourceTypeBinding enclosingType = currentEnclosing.referenceContext.binding;
 			TypeBinding currentTarget = targetClass;
 			while (currentTarget != null) {
-				if (currentTarget instanceof ParameterizedTypeBinding)
-					currentTarget = currentTarget.actualType();
-				if (TypeBinding.equalsEquals(enclosingType, currentTarget)) {
+				if (TypeBinding.equalsEquals(enclosingType, currentTarget.actualType())) {
 					if (currentEnclosing.insideEarlyConstructionContext)
 						return enclosingType;
 				}
diff --git a/org.eclipse.jdt.core.compiler.batch/src/org/eclipse/jdt/internal/compiler/lookup/SourceTypeBinding.java b/org.eclipse.jdt.core.compiler.batch/src/org/eclipse/jdt/internal/compiler/lookup/SourceTypeBinding.java
index 74f662a2dcf..d7decbf7178 100644
--- a/org.eclipse.jdt.core.compiler.batch/src/org/eclipse/jdt/internal/compiler/lookup/SourceTypeBinding.java
+++ b/org.eclipse.jdt.core.compiler.batch/src/org/eclipse/jdt/internal/compiler/lookup/SourceTypeBinding.java
@@ -1227,7 +1227,7 @@ else if (this.isInterface())
 			continue;
 		if (this.isClass()) {
 			ReferenceBinding permSuperType = permittedType.superclass();
-			permSuperType = getActualType(permSuperType);
+			permSuperType = permSuperType.actualType();
 			if (!TypeBinding.equalsEquals(this, permSuperType)) {
 				this.scope.problemReporter().sealedNotDirectSuperClass(permittedType, permittedTypeRef, this);
 				continue;
@@ -1237,7 +1237,7 @@ else if (this.isInterface())
 			boolean foundSuperInterface = false;
 			if (permSuperInterfaces != null) {
 				for (ReferenceBinding psi : permSuperInterfaces) {
-					psi = getActualType(psi);
+					psi = psi.actualType();
 					if (TypeBinding.equalsEquals(this, psi)) {
 						foundSuperInterface = true;
 						break;
@@ -1298,9 +1298,6 @@ private void reportSealedSuperTypeDoesNotPermitProblem(TypeReference superTypeRe
 	}
 }
 
-private ReferenceBinding getActualType(ReferenceBinding ref) {
-	return ref.isParameterizedType() || ref.isRawType() ? ref.actualType(): ref;
-}
 public List<SourceTypeBinding> collectAllTypeBindings(TypeDeclaration typeDecl, CompilationUnitScope unitScope) {
 	class TypeBindingsCollector extends ASTVisitor {
 		List<SourceTypeBinding> types = new ArrayList<>();
@@ -1341,10 +1338,10 @@ private boolean checkPermitsAndAdd(ReferenceBinding superType) {
 			|| !superType.isSealed())
 		return true;
 	if (superType.isSealed()) {
-		superType = getActualType(superType);
+		superType = superType.actualType();
 		ReferenceBinding[] superPermittedTypes = superType.permittedTypes();
 		for (ReferenceBinding permittedType : superPermittedTypes) {
-			permittedType = getActualType(permittedType);
+			permittedType = permittedType.actualType();
 			if (permittedType.isValidBinding() && TypeBinding.equalsEquals(this, permittedType))
 				return true;
 		}
diff --git a/org.eclipse.jdt.core.compiler.batch/src/org/eclipse/jdt/internal/compiler/lookup/TypeBinding.java b/org.eclipse.jdt.core.compiler.batch/src/org/eclipse/jdt/internal/compiler/lookup/TypeBinding.java
index ce91f97244a..3746eafca0a 100644
--- a/org.eclipse.jdt.core.compiler.batch/src/org/eclipse/jdt/internal/compiler/lookup/TypeBinding.java
+++ b/org.eclipse.jdt.core.compiler.batch/src/org/eclipse/jdt/internal/compiler/lookup/TypeBinding.java
@@ -168,7 +168,8 @@ public static final TypeBinding wellKnownBaseType(int id) {
 }
 
 public ReferenceBinding actualType() {
-	return null; // overridden in ParameterizedTypeBinding & WildcardBinding
+	assert false : "Invocation on non-ReferenceBinding not expected"; //$NON-NLS-1$
+	return null; // overridden in ReferenceBinding, ParameterizedTypeBinding & WildcardBinding
 }
 
 TypeBinding [] additionalBounds() {