Used ConvertMemberToExtensionIntention in MigrateExternalExtensionFix instead of manually creating extension method

idea/src/org/jetbrains/kotlin/idea/intentions/declarations/ConvertMemberToExtensionIntention.kt

@@ -54,6 +54,27 @@ class ConvertMemberToExtensionIntention : SelfTargetingRangeIntention<KtCallable
     //TODO: local class
 
     override fun applyTo(element: KtCallableDeclaration, editor: Editor?) {
+        val (extension, bodyToSelect) = createExtensionCallableAndPrepareBodyToSelect(element)
+
+        editor?.apply {
+            unblockDocument()
+
+            if (bodyToSelect != null) {
+                val range = bodyToSelect!!.textRange
+                moveCaret(range.startOffset, ScrollType.CENTER)
+                selectionModel.setSelection(range.startOffset, range.endOffset)
+            }
+            else {
+                moveCaret(extension.textOffset, ScrollType.CENTER)
+            }
+        }
+    }
+
+    fun convert(element: KtCallableDeclaration): KtCallableDeclaration {
+        return createExtensionCallableAndPrepareBodyToSelect(element).first
+    }
+
+    private fun createExtensionCallableAndPrepareBodyToSelect(element: KtCallableDeclaration): Pair<KtCallableDeclaration, KtExpression?> {
         val descriptor = element.resolveToDescriptor()
         val containingClass = descriptor.containingDeclaration as ClassDescriptor
 
@@ -179,18 +200,7 @@ class ConvertMemberToExtensionIntention : SelfTargetingRangeIntention<KtCallable
             }
         }
 
-        editor?.apply {
+        return extension to bodyToSelect
-            unblockDocument()
-
-            if (bodyToSelect != null) {
-                val range = bodyToSelect!!.textRange
-                moveCaret(range.startOffset, ScrollType.CENTER)
-                selectionModel.setSelection(range.startOffset, range.endOffset)
-            }
-            else {
-                moveCaret(extension.textOffset, ScrollType.CENTER)
-            }
-        }
     }
 
     private fun newTypeParameterList(member: KtCallableDeclaration): KtTypeParameterList? {

idea/src/org/jetbrains/kotlin/idea/quickfix/migration/MigrateExternalExtensionFix.kt

@@ -21,19 +21,16 @@ import com.intellij.openapi.editor.Editor
 import com.intellij.openapi.project.Project
 import com.intellij.psi.PsiElement
 import org.jetbrains.kotlin.builtins.KotlinBuiltIns
-import org.jetbrains.kotlin.descriptors.ClassDescriptor
 import org.jetbrains.kotlin.descriptors.annotations.checkAnnotationName
 import org.jetbrains.kotlin.diagnostics.Diagnostic
 import org.jetbrains.kotlin.diagnostics.Errors
 import org.jetbrains.kotlin.idea.caches.resolve.analyze
-import org.jetbrains.kotlin.idea.caches.resolve.resolveToDescriptor
-import org.jetbrains.kotlin.idea.core.setReceiverType
 import org.jetbrains.kotlin.idea.intentions.SpecifyTypeExplicitlyIntention
+import org.jetbrains.kotlin.idea.intentions.declarations.ConvertMemberToExtensionIntention
 import org.jetbrains.kotlin.idea.project.builtIns
 import org.jetbrains.kotlin.idea.quickfix.CleanupFix
 import org.jetbrains.kotlin.idea.quickfix.KotlinQuickFixAction
 import org.jetbrains.kotlin.idea.quickfix.KotlinSingleIntentionActionFactory
-import org.jetbrains.kotlin.idea.quickfix.createFromUsage.callableBuilder.*
 import org.jetbrains.kotlin.idea.util.addAnnotation
 import org.jetbrains.kotlin.js.PredefinedAnnotation
 import org.jetbrains.kotlin.js.resolve.diagnostics.ErrorsJs
@@ -67,24 +64,19 @@ class MigrateExternalExtensionFix(declaration: KtNamedDeclaration)
     }
 
     private fun fixNativeClass(containingClass: KtClassOrObject, project: Project, editor: Editor?, file: KtFile) {
-        val membersToFix = containingClass.declarations.filterIsInstance<KtNamedDeclaration>().filter { isMemberDeclaration(it) }. map {
+        val membersToFix = containingClass.declarations.filterIsInstance<KtCallableDeclaration>().filter { isMemberDeclaration(it) }. map {
              it to fetchJsNativeAnnotations(it)
         }.filter {
             it.second.annotations.isNotEmpty()
         }
 
-        var anchor: PsiElement = containingClass
+        membersToFix.asReversed().forEach { (memberDeclaration, annotations) ->
-        membersToFix.forEach { (memberDeclaration, annotations) ->
             if (annotations.nativeAnnotation != null && !annotations.isGetter && !annotations.isSetter && !annotations.isInvoke) {
                 convertNativeAnnotationToJsName(memberDeclaration, annotations)
                 annotations.nativeAnnotation.delete()
             } else {
-                // TODO: find references
+                val externalDeclaration = ConvertMemberToExtensionIntention().convert(memberDeclaration)
-                createExtensionDeclaration(memberDeclaration, project, anchor)?.let { externalDeclaration ->
+                fixExtensionMemberDeclaration(externalDeclaration, project, null, file)
-                    memberDeclaration.delete()
-                    fixExtensionMemberDeclaration(externalDeclaration, project, null, file)
-                    anchor = externalDeclaration
-                }
             }
         }
 
@@ -93,55 +85,6 @@ class MigrateExternalExtensionFix(declaration: KtNamedDeclaration)
         fixAnnotations(containingClass, classAnnotations, null)
     }
 
-    private fun createExtensionDeclaration(declaration: KtNamedDeclaration, project: Project, anchor: PsiElement): KtNamedDeclaration? {
-        val containingClass = declaration.containingClassOrObject ?: return null
-        val builder = KtPsiFactory.CallableBuilder(if (declaration is KtNamedFunction) KtPsiFactory.CallableBuilder.Target.FUNCTION else KtPsiFactory.CallableBuilder.Target.READ_ONLY_PROPERTY)
-
-        // modifiers
-        declaration.annotationEntries.forEach {
-            builder.modifier(it.text)
-        }
-
-        // type parameters
-        builder.typeParams(containingClass.typeParameters.union((declaration as? KtTypeParameterListOwner)?.typeParameters ?: emptyList()).map { it.text })
-
-        // receiver
-        builder.receiver(containingClass.name ?: "XXX")
-
-        // name
-        builder.name(declaration.nameAsSafeName.identifier)
-
-        // parameters
-        (declaration as? KtCallableDeclaration)?.valueParameters?.forEach {
-            builder.param(it.nameAsSafeName.identifier, it.typeReference?.text ?: "XXX", it.defaultValue?.text)
-        }
-
-        // return type
-        val returnTypeReference = declaration.getReturnTypeReference()
-        if (returnTypeReference != null)
-            builder.returnType(returnTypeReference.text)
-        else
-            builder.noReturnType()
-
-        // body
-        (declaration as? KtDeclarationWithBody)?.bodyExpression?.let {
-            builder.blockBody(it.text)
-        }
-
-        // Create function etc
-        var newFunctionText = builder.asString()
-        val psiFactory = KtPsiFactory(project)
-        val newFunction = psiFactory.createFunction(newFunctionText)
-
-        val parent = anchor.parent
-        val result = parent.addAfter(newFunction, anchor) as KtCallableDeclaration
-        parent.addBefore(psiFactory.createNewLine(2), result)
-
-        // fix receiver type
-        result.setReceiverType((containingClass.resolveToDescriptor(BodyResolveMode.PARTIAL) as ClassDescriptor).defaultType)
-        return result
-    }
-
     private data class JsNativeAnnotations(val annotations: List<KtAnnotationEntry>, val nativeAnnotation: KtAnnotationEntry?, val isGetter: Boolean, val isSetter: Boolean, val isInvoke: Boolean)
 
     private fun fetchJsNativeAnnotations(declaration: KtNamedDeclaration) : JsNativeAnnotations {

idea/testData/quickfix/migration/jsExternal/nativeMemberAll01.kt.after

@@ -20,6 +20,6 @@ inline fun B.bar(a: B) {
 }
 
 @Suppress("NOTHING_TO_INLINE")
-inline fun <T> B.exp(t: T) {
+inline fun<T> B.exp(t: T) {
     asDynamic()(t)
 }

idea/testData/quickfix/migration/jsExternal/nativeMemberAll02.kt.after

@@ -20,6 +20,6 @@ inline fun B.bar(a: B) {
 }
 
 @Suppress("NOTHING_TO_INLINE")
-inline fun <T> B.exp(t: T) {
+inline fun<T> B.exp(t: T) {
     asDynamic()(t)
 }

idea/testData/quickfix/migration/jsExternal/nativeMemberAll03.kt.after

@@ -20,6 +20,6 @@ inline fun B.bar(a: B) {
 }
 
 @Suppress("NOTHING_TO_INLINE")
-inline fun <T> B.exp(t: T) {
+inline fun<T> B.exp(t: T) {
     asDynamic()(t)
 }

idea/testData/quickfix/migration/jsExternal/nativeMemberInvokeGenericFun.kt.after

@@ -5,6 +5,6 @@ external class B {
 }
 
 @Suppress("NOTHING_TO_INLINE")
-inline fun <T> B.exp(t: T) {
+inline fun<T> B.exp(t: T) {
     asDynamic()(t)
 }