minor ObjectIntrinsics refactoring

js/js.translator/src/org/jetbrains/kotlin/js/translate/intrinsic/Intrinsics.kt

@@ -43,7 +43,7 @@ class Intrinsics {
         return functionIntrinsics.getIntrinsic(descriptor)
     }
 
-    fun getObjectIntrinsic(classDescriptor: ClassDescriptor): ObjectIntrinsic {
+    fun getObjectIntrinsic(classDescriptor: ClassDescriptor): ObjectIntrinsic? {
         return objectIntrinsics.getIntrinsic(classDescriptor)
     }
 }

js/js.translator/src/org/jetbrains/kotlin/js/translate/intrinsic/objects/objectsIntrinsics.kt

@@ -30,15 +30,21 @@ class DefaultClassObjectIntrinsic( val fqName: FqName): ObjectIntrinsic {
 }
 
 class ObjectIntrinsics {
-    private val cache = mutableMapOf<ClassDescriptor, ObjectIntrinsic>()
+    private val cache = mutableMapOf<ClassDescriptor, ObjectIntrinsic?>()
 
-    fun getIntrinsic(classDescriptor: ClassDescriptor) = cache.getOrPut(classDescriptor) { createIntrinsic(classDescriptor) }
+    fun getIntrinsic(classDescriptor: ClassDescriptor): ObjectIntrinsic? {
+        if (classDescriptor in cache) return cache[classDescriptor]
 
-    private fun createIntrinsic(classDescriptor: ClassDescriptor): ObjectIntrinsic {
+        return createIntrinsic(classDescriptor).also {
+            cache[classDescriptor] = it
+        }
+    }
+
+    private fun createIntrinsic(classDescriptor: ClassDescriptor): ObjectIntrinsic? {
         if (classDescriptor.fqNameUnsafe == KotlinBuiltIns.FQ_NAMES._enum ||
             !CompanionObjectMapping.isMappedIntrinsicCompanionObject(classDescriptor)
         ) {
-            return NO_OBJECT_INTRINSIC
+            return null
         }
 
         val containingDeclaration = classDescriptor.containingDeclaration
@@ -50,12 +56,4 @@ class ObjectIntrinsics {
 
 interface ObjectIntrinsic {
     fun apply(context: TranslationContext): JsExpression
-    fun exists(): Boolean = true
-}
-
-object NO_OBJECT_INTRINSIC : ObjectIntrinsic {
-    override fun apply(context: TranslationContext): JsExpression =
-            throw UnsupportedOperationException("ObjectIntrinsic#NO_OBJECT_INTRINSIC_#apply")
-
-    override fun exists(): Boolean = false
 }

js/js.translator/src/org/jetbrains/kotlin/js/translate/reference/CompanionObjectIntrinsicAccessTranslator.java

@@ -44,7 +44,7 @@ public class CompanionObjectIntrinsicAccessTranslator extends AbstractTranslator
             @NotNull TranslationContext context
     ) {
         DeclarationDescriptor descriptor = getDescriptorForReferenceExpression(context.bindingContext(), expression);
-        return descriptor instanceof ClassDescriptor && context.intrinsics().getObjectIntrinsic((ClassDescriptor) descriptor).exists();
+        return descriptor instanceof ClassDescriptor && context.intrinsics().getObjectIntrinsic((ClassDescriptor) descriptor) != null;
     }
 
     @NotNull