Seal KSNode

KSNodeDescriptorImpl, KSNodeJavaImpl and KSNodeKtImpl were removed
because they were unused but inherited from the now sealed KSNode.

Author: lukellmann

api/api.base

@@ -401,7 +401,7 @@ package com.google.devtools.ksp.symbol {
     method @NonNull public String getShortName();
   }
 
-  public interface KSNode {
+  public sealed interface KSNode {
     method public <D, R> R accept(@NonNull com.google.devtools.ksp.symbol.KSVisitor<D,R> visitor, D data);
     method @NonNull public com.google.devtools.ksp.symbol.Location getLocation();
     method @NonNull public com.google.devtools.ksp.symbol.Origin getOrigin();

api/src/main/kotlin/com/google/devtools/ksp/symbol/KSNode.kt

@@ -19,7 +19,7 @@ package com.google.devtools.ksp.symbol
 /**
  * Base class of every visitable program elements.
  */
-interface KSNode {
+sealed interface KSNode {
     val origin: Origin
     val location: Location
     val parent: KSNode?

compiler-plugin/src/main/kotlin/com/google/devtools/ksp/processing/impl/ResolverImpl.kt

@@ -627,6 +627,11 @@ class ResolverImpl(
                     resolverContext = resolverContext
                         .childForClassOrPackage(resolveJavaDeclaration(e.psi) as ClassDescriptor, JavaClassImpl(e.psi))
                 }
+                is KSClassDeclaration, is KSFunctionDeclaration, is KSPropertyDeclaration, is KSTypeAlias,
+                is KSTypeParameter, is KSFile, is KSPropertyGetter, is KSPropertySetter, is KSTypeArgument,
+                is KSTypeReference, is KSValueArgument, is KSValueParameter, is KSAnnotation, is KSCallableReference,
+                is KSClassifierReference, is KSDefNonNullReference, is KSDynamicReference, is KSParenthesizedReference,
+                -> Unit
             }
         }
         return if (javaType is JavaArrayTypeImpl)