IR JS: support findAssociatedObject feature (KT-37418 fixed)

js/js.frontend/src/org/jetbrains/kotlin/js/resolve/diagnostics/JsReflectionAPICallChecker.kt

@@ -18,11 +18,20 @@ package org.jetbrains.kotlin.js.resolve.diagnostics
 
 import com.intellij.psi.PsiElement
 import org.jetbrains.kotlin.builtins.ReflectionTypes
+import org.jetbrains.kotlin.descriptors.CallableDescriptor
+import org.jetbrains.kotlin.descriptors.ClassDescriptor
 import org.jetbrains.kotlin.diagnostics.Errors.UNSUPPORTED
+import org.jetbrains.kotlin.name.FqName
 import org.jetbrains.kotlin.resolve.calls.checkers.AbstractReflectionApiCallChecker
 import org.jetbrains.kotlin.resolve.calls.checkers.CallCheckerContext
+import org.jetbrains.kotlin.resolve.descriptorUtil.fqNameSafe
 import org.jetbrains.kotlin.storage.StorageManager
 
+private val ADDITIONAL_ALLOWED_CLASSES = setOf(
+    FqName("kotlin.reflect.AssociatedObjectKey"),
+    FqName("kotlin.reflect.ExperimentalAssociatedObjects")
+)
+
 class JsReflectionAPICallChecker(
     reflectionTypes: ReflectionTypes,
     storageManager: StorageManager
@@ -30,6 +39,12 @@ class JsReflectionAPICallChecker(
     override val isWholeReflectionApiAvailable: Boolean
         get() = false
 
+    override fun isAllowedReflectionApi(descriptor: CallableDescriptor, containingClass: ClassDescriptor): Boolean {
+        return super.isAllowedReflectionApi(descriptor, containingClass) ||
+                containingClass.fqNameSafe in ADDITIONAL_ALLOWED_CLASSES ||
+                descriptor.name.asString() == "findAssociatedObject"
+    }
+
     override fun report(element: PsiElement, context: CallCheckerContext) {
         context.trace.report(UNSUPPORTED.on(element, "This reflection API is not supported yet in JavaScript"))
     }