Add toArray to IArray

Author: mpilquist

library/src/scala/IArray.scala

@@ -259,6 +259,10 @@ object opaques:
     extension [T](arr: IArray[T]) def takeWhile(p: T => Boolean): IArray[T] =
       genericArrayOps(arr).takeWhile(p)
 
+    /** Returns a mutable copy of this immutable array. */
+    extension [T](arr: IArray[T]) def toArray: Array[T] =
+      arr.clone.asInstanceOf[Array[T]]
+
     /** Converts an array of pairs into an array of first elements and an array of second elements. */
     extension [U: ClassTag, V: ClassTag](arr: IArray[(U, V)]) def unzip: (IArray[U], IArray[V]) =
       genericArrayOps(arr).unzip

tests/run/iarrays.scala

@@ -79,4 +79,8 @@ object Test extends App {
   val fs: Array[Any] = new Array[Any](10)
   ds.copyToArray(fs, 5, 2)
   assert(fs.toList == List(null, null, null, null, null, 1, 2, null, null, null))
+
+  // Check toArray
+  ds.toArray(0) = 0
+  assert(ds(0) == 1)
 }