Change Signature: Fix implicit receiver ->argument convertion in recusrive calls

#KT-8744 In Progress

idea/src/org/jetbrains/kotlin/idea/refactoring/changeSignature/KotlinChangeSignatureProcessor.kt

@@ -30,6 +30,8 @@ import com.intellij.refactoring.rename.UnresolvableCollisionUsageInfo
 import com.intellij.usageView.UsageInfo
 import com.intellij.usageView.UsageViewDescriptor
 import com.intellij.util.containers.MultiMap
+import org.jetbrains.kotlin.idea.refactoring.changeSignature.usages.KotlinFunctionCallUsage
+import org.jetbrains.kotlin.idea.refactoring.changeSignature.usages.KotlinImplicitReceiverUsage
 import org.jetbrains.kotlin.idea.refactoring.changeSignature.usages.KotlinUsageInfo
 import org.jetbrains.kotlin.idea.refactoring.changeSignature.usages.KotlinWrapperForJavaUsageInfos
 import java.util.*
@@ -87,6 +89,8 @@ class KotlinChangeSignatureProcessor(project: Project,
 
         val usageArray = usagesSet.toTypedArray()
         Arrays.sort(usageArray) { u1, u2 ->
+            if (u1 is KotlinImplicitReceiverUsage && u2 is KotlinFunctionCallUsage) return@sort -1
+            if (u2 is KotlinImplicitReceiverUsage && u1 is KotlinFunctionCallUsage) return@sort 1
             val element1 = u1.element
             val element2 = u2.element
             val rank1 = if (element1 != null) element1.textOffset else -1

idea/src/org/jetbrains/kotlin/idea/refactoring/changeSignature/usages/KotlinFunctionCallUsage.kt

@@ -298,6 +298,12 @@ class KotlinFunctionCallUsage(
         }
     }
 
+    private fun ExpressionReceiver.wrapInvalidated(element: KtCallElement): ExpressionReceiver {
+        return object: ExpressionReceiver by this {
+            override val expression = element.getQualifiedExpressionForSelector()!!.receiverExpression
+        }
+    }
+
     private fun updateArgumentsAndReceiver(changeInfo: KotlinChangeInfo, element: KtCallElement, allUsages: Array<out UsageInfo>) {
         if (isPropertyJavaUsage) return updateJavaPropertyCall(changeInfo, element)
 
@@ -321,7 +327,12 @@ class KotlinFunctionCallUsage(
             val (index, param) = it
             val oldIndex = param.oldIndex
             val resolvedArgument = if (oldIndex >= 0) getResolvedValueArgument(oldIndex) else null
-            val receiverValue = if (param == originalReceiverInfo) extensionReceiver else null
+            var receiverValue = if (param == originalReceiverInfo) extensionReceiver else null
+            // Workaround for recursive calls where implicit extension receiver is transformed into ordinary value argument
+            // Receiver expression retained in the original resolved call is no longer valid at this point
+            if (receiverValue is ExpressionReceiver && !receiverValue.expression.isValid) {
+                receiverValue = receiverValue.wrapInvalidated(element)
+            }
             ArgumentInfo(param, index, resolvedArgument, receiverValue as? ReceiverValue)
         }
 

idea/testData/refactoring/changeSignature/ImplicitReceiverInRecursiveCallAfter.kt

@@ -0,0 +1,5 @@
+interface A {
+    val parent: A
+}
+
+fun ext(a: A): Int = 1 + ext(a.parent)

idea/testData/refactoring/changeSignature/ImplicitReceiverInRecursiveCallBefore.kt

@@ -0,0 +1,5 @@
+interface A {
+    val parent: A
+}
+
+fun A.<caret>ext(): Int = 1 + parent.ext()

idea/tests/org/jetbrains/kotlin/idea/refactoring/changeSignature/KotlinChangeSignatureTest.kt

@@ -944,4 +944,9 @@ class KotlinChangeSignatureTest : KotlinCodeInsightTestCase() {
                                             psiFactory.createExpression("5"),
                                             KotlinValVar.Val))
     }
+
+    fun testImplicitReceiverInRecursiveCall() = doTest {
+        receiverParameterInfo = null
+        newParameters[0].name = "a"
+    }
 }