From f22133be7ec0fdd52a967947fb2caf2b4c470f1d Mon Sep 17 00:00:00 2001
From: Toshiaki Kameyama <kmymtsak@gmail.com>
Date: Tue, 9 Oct 2018 05:46:52 +0300
Subject: [PATCH] Call chain into sequence refactoring: introduce & use
 isIterable

Related to KT-26650
---
 .../ConvertCallChainIntoSequenceInspection.kt            | 6 +-----
 .../kotlin/idea/inspections/collections/FunctionUtils.kt | 9 +++++++++
 2 files changed, 10 insertions(+), 5 deletions(-)

diff --git a/idea/src/org/jetbrains/kotlin/idea/inspections/collections/ConvertCallChainIntoSequenceInspection.kt b/idea/src/org/jetbrains/kotlin/idea/inspections/collections/ConvertCallChainIntoSequenceInspection.kt
index e240d618633..a6b45cf906a 100644
--- a/idea/src/org/jetbrains/kotlin/idea/inspections/collections/ConvertCallChainIntoSequenceInspection.kt
+++ b/idea/src/org/jetbrains/kotlin/idea/inspections/collections/ConvertCallChainIntoSequenceInspection.kt
@@ -16,7 +16,6 @@ import com.intellij.openapi.ui.LabeledComponent
 import com.intellij.psi.PsiWhiteSpace
 import com.intellij.ui.EditorTextField
 import org.jetbrains.kotlin.builtins.DefaultBuiltIns
-import org.jetbrains.kotlin.descriptors.ClassDescriptor
 import org.jetbrains.kotlin.idea.caches.resolve.analyze
 import org.jetbrains.kotlin.idea.core.replaced
 import org.jetbrains.kotlin.idea.inspections.AbstractKotlinInspection
@@ -28,11 +27,8 @@ import org.jetbrains.kotlin.psi.psiUtil.*
 import org.jetbrains.kotlin.resolve.BindingContext
 import org.jetbrains.kotlin.resolve.calls.callUtil.getResolvedCall
 import org.jetbrains.kotlin.resolve.calls.resolvedCallUtil.getImplicitReceiverValue
-import org.jetbrains.kotlin.resolve.descriptorUtil.fqNameSafe
-import org.jetbrains.kotlin.resolve.descriptorUtil.isSubclassOf
 import org.jetbrains.kotlin.resolve.lazy.BodyResolveMode
 import org.jetbrains.kotlin.resolve.scopes.receivers.ImplicitReceiver
-import org.jetbrains.kotlin.types.KotlinType
 import java.awt.BorderLayout
 import javax.swing.JPanel
 
@@ -154,7 +150,7 @@ private fun KtQualifiedExpression.findCallChain(): CallChain? {
     val receiverType =
         (lastCall.getQualifiedExpressionForSelector())?.receiverExpression?.getResolvedCall(context)?.resultingDescriptor?.returnType
             ?: lastCall.implicitReceiver(context)?.type
-    if (receiverType?.isMap(DefaultBuiltIns.Instance) == true) return null
+    if (receiverType?.isIterable(DefaultBuiltIns.Instance) != true) return null
 
     val firstCall = calls.first()
     val qualified = firstCall.getQualifiedExpressionForSelector() ?: firstCall.getQualifiedExpressionForReceiver() ?: return null
diff --git a/idea/src/org/jetbrains/kotlin/idea/inspections/collections/FunctionUtils.kt b/idea/src/org/jetbrains/kotlin/idea/inspections/collections/FunctionUtils.kt
index 441a0112ead..d35dec1e307 100644
--- a/idea/src/org/jetbrains/kotlin/idea/inspections/collections/FunctionUtils.kt
+++ b/idea/src/org/jetbrains/kotlin/idea/inspections/collections/FunctionUtils.kt
@@ -39,6 +39,15 @@ fun KotlinType?.isMap(builtIns: KotlinBuiltIns): Boolean {
     return classDescriptor.name.asString().endsWith("Map") && classDescriptor.isSubclassOf(builtIns.map)
 }
 
+fun KotlinType?.isIterable(builtIns: KotlinBuiltIns): Boolean {
+    val classDescriptor = this?.constructor?.declarationDescriptor as? ClassDescriptor ?: return false
+    val className = classDescriptor.name.asString()
+    // First two lines are just to make things faster
+    return className.endsWith("List") && classDescriptor.isSubclassOf(builtIns.list)
+            || className.endsWith("Set") && classDescriptor.isSubclassOf(builtIns.set)
+            || classDescriptor.isSubclassOf(builtIns.iterable)
+}
+
 fun KtCallExpression.isCalling(fqName: FqName, context: BindingContext = analyze(BodyResolveMode.PARTIAL)): Boolean {
     val function = fqName.asString().takeLastWhile { it != '.' }
     if (calleeExpression?.text != function) return false