Implement conversion from typed array and collection to UArrays

libraries/tools/kotlin-stdlib-gen/src/templates/Arrays.kt

@@ -322,26 +322,35 @@ object ArrayOps : TemplateGroupBase() {
     }
 
     val f_toPrimitiveArray = fn("toPrimitiveArray()") {
-        include(ArraysOfObjects, PrimitiveType.defaultPrimitives)
-        include(Collections, PrimitiveType.defaultPrimitives)
+        include(ArraysOfObjects, PrimitiveType.values().toSet())
+        include(Collections, PrimitiveType.values().toSet())
     } builder {
         val primitive = checkNotNull(primitive)
         val arrayType = primitive.name + "Array"
         signature("to$arrayType()")
         returns(arrayType)
+
+        if (primitive in PrimitiveType.unsignedPrimitives) {
+            since("1.3")
+            annotation("@ExperimentalUnsignedTypes")
+        }
+
         // TODO: Use different implementations for JS
         specialFor(ArraysOfObjects) {
+            if (primitive in PrimitiveType.unsignedPrimitives) {
+                sourceFile(SourceFile.UArrays)
+            }
             doc { "Returns an array of ${primitive.name} containing all of the elements of this generic array." }
             body {
                 """
-                val result = $arrayType(size)
-                for (index in indices)
-                    result[index] = this[index]
-                return result
+                return $arrayType(size) { index -> this[index] }
                 """
             }
         }
         specialFor(Collections) {
+            if (primitive in PrimitiveType.unsignedPrimitives) {
+                sourceFile(SourceFile.UCollections)
+            }
             doc { "Returns an array of ${primitive.name} containing all of the elements of this collection." }
             body {
                 """

libraries/tools/kotlin-stdlib-gen/src/templates/dsl/SourceFile.kt

@@ -10,6 +10,7 @@ enum class SourceFile(jvmClassName: String? = null, val multifile: Boolean = tru
     Arrays(packageName = "kotlin.collections"),
     UArrays(packageName = "kotlin.collections"),
     Collections(packageName = "kotlin.collections"),
+    UCollections(packageName = "kotlin.collections"),
     Sets(packageName = "kotlin.collections"),
     Maps(packageName = "kotlin.collections"),
     Sequences(packageName = "kotlin.sequences"),