From 1c1492da3ddcdcd27c64d9eacb2e3ea12e3bd186 Mon Sep 17 00:00:00 2001
From: Abduqodiri Qurbonzoda <abduqodiri.qurbonzoda@jetbrains.com>
Date: Tue, 2 Mar 2021 10:45:00 +0300
Subject: [PATCH] Optimize K/N ArrayList.toArray #KT-42720

---
 .../kotlin/kotlin/collections/ArrayList.kt    | 20 +++++++++++++++++++
 1 file changed, 20 insertions(+)

diff --git a/kotlin-native/runtime/src/main/kotlin/kotlin/collections/ArrayList.kt b/kotlin-native/runtime/src/main/kotlin/kotlin/collections/ArrayList.kt
index 553fa452b73..bca09b4a0f7 100644
--- a/kotlin-native/runtime/src/main/kotlin/kotlin/collections/ArrayList.kt
+++ b/kotlin-native/runtime/src/main/kotlin/kotlin/collections/ArrayList.kt
@@ -164,6 +164,26 @@ actual class ArrayList<E> private constructor(
         return array.subarrayContentToString(offset, length)
     }
 
+    @Suppress("UNCHECKED_CAST")
+    override fun <T> toArray(destination: Array<T>): Array<T> {
+        if (destination.size < length) {
+            return array.copyOfRange(fromIndex = offset, toIndex = offset + length) as Array<T>
+        }
+
+        (array as Array<T>).copyInto(destination, 0, startIndex = offset, endIndex = offset + length)
+
+        if (destination.size > length) {
+            destination[length] = null as T // null-terminate
+        }
+
+        return destination
+    }
+
+    override fun toArray(): Array<Any?> {
+        @Suppress("UNCHECKED_CAST")
+        return array.copyOfRange(fromIndex = offset, toIndex = offset + length) as Array<Any?>
+    }
+
     // ---------------------------- private ----------------------------
 
     private fun checkElementIndex(index: Int) {