From 648330da501bd1b2f5f5508508679a189e1127f1 Mon Sep 17 00:00:00 2001
From: Roman Golyshev <roman.golyshev@jetbrains.com>
Date: Mon, 16 Oct 2023 17:42:08 +0200
Subject: [PATCH] [kotlin] Make `SmartSet` implement `MutableSet` for more
 type-safety

`AbstractSet` is a java class, and it brings flexible types with it.
Because of it, it was possible to write the following code:

```kt
fun usage() {
  val mySet = SmartSet.create<String>() // should not contain nulls
  mySet += null // compiles because of flexible types
}
```

Using `AbstractMutableSet`
as a base class does not change the implementation,
but explicitly adds a proper kotlin `MutableSet`
interface to the class, making it more type-safe
---
 core/util.runtime/src/org/jetbrains/kotlin/utils/SmartSet.kt | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/core/util.runtime/src/org/jetbrains/kotlin/utils/SmartSet.kt b/core/util.runtime/src/org/jetbrains/kotlin/utils/SmartSet.kt
index 64a71eca352..71f8657dd82 100644
--- a/core/util.runtime/src/org/jetbrains/kotlin/utils/SmartSet.kt
+++ b/core/util.runtime/src/org/jetbrains/kotlin/utils/SmartSet.kt
@@ -25,7 +25,7 @@ import java.util.*
  * Also, [iterator] returns an iterator which does not support [MutableIterator.remove].
  */
 @Suppress("UNCHECKED_CAST")
-class SmartSet<T> private constructor() : AbstractSet<T>() {
+class SmartSet<T> private constructor() : AbstractMutableSet<T>() {
     companion object {
         private const val ARRAY_THRESHOLD = 5