Implement fill extension function for UArrays (KT-28339)

libraries/stdlib/jvm/src/generated/_UArraysJvm.kt

@@ -142,3 +142,38 @@ public fun UShortArray.binarySearch(element: UShort, fromIndex: Int = 0, toIndex
     return -(low + 1)  // key not found
 }
 
+/**
+ * Fills original array with the provided value.
+ */
+@SinceKotlin("1.3")
+@ExperimentalUnsignedTypes
+public fun UIntArray.fill(element: UInt, fromIndex: Int = 0, toIndex: Int = size): Unit {
+    storage.fill(element.toInt(), fromIndex, toIndex)
+}
+
+/**
+ * Fills original array with the provided value.
+ */
+@SinceKotlin("1.3")
+@ExperimentalUnsignedTypes
+public fun ULongArray.fill(element: ULong, fromIndex: Int = 0, toIndex: Int = size): Unit {
+    storage.fill(element.toLong(), fromIndex, toIndex)
+}
+
+/**
+ * Fills original array with the provided value.
+ */
+@SinceKotlin("1.3")
+@ExperimentalUnsignedTypes
+public fun UByteArray.fill(element: UByte, fromIndex: Int = 0, toIndex: Int = size): Unit {
+    storage.fill(element.toByte(), fromIndex, toIndex)
+}
+
+/**
+ * Fills original array with the provided value.
+ */
+@SinceKotlin("1.3")
+@ExperimentalUnsignedTypes
+public fun UShortArray.fill(element: UShort, fromIndex: Int = 0, toIndex: Int = size): Unit {
+    storage.fill(element.toShort(), fromIndex, toIndex)
+}

libraries/stdlib/jvm/test/collections/UArrayJVMTest.kt

@@ -6,6 +6,7 @@
 package test.collections
 
 import kotlin.test.Test
+import kotlin.test.assertTrue
 import kotlin.test.assertEquals
 import kotlin.test.assertFailsWith
 
@@ -66,6 +67,55 @@ class UArrayJVMTest {
         test(array, UIntArray::binarySearch, operations, UInt::toUInt)
         test(array.toULongArray(), ULongArray::binarySearch, operations, UInt::toULong)
     }
+
+    @Test
+    fun fill() {
+        fun <A, E> testFailures(array: A, fill: A.(E, Int, Int) -> Unit, element: E, arraySize: Int) {
+            assertFailsWith<ArrayIndexOutOfBoundsException> {
+                array.fill(element, -1, arraySize)
+            }
+            assertFailsWith<ArrayIndexOutOfBoundsException> {
+                array.fill(element, 0, arraySize + 1)
+            }
+            assertFailsWith<IllegalArgumentException> {
+                array.fill(element, 1, 0)
+            }
+        }
+
+        testFailures(UByteArray(5) { it.toUByte() }, UByteArray::fill, 0u, 5)
+        testFailures(UShortArray(5) { it.toUShort() }, UShortArray::fill, 0u, 5)
+        testFailures(UIntArray(5) { it.toUInt() }, UIntArray::fill, 0u, 5)
+        testFailures(ULongArray(5) { it.toULong() }, ULongArray::fill, 0u, 5)
+
+        fun <A, E> test(
+            array: UIntArray,
+            fill: A.(E, Int, Int) -> Unit,
+            operations: List<OperationOnRange<UInt, UIntArray>>,
+            arrayTransform: UIntArray.() -> A,
+            elementTransform: UInt.() -> E,
+            contentEquals: A.(A) -> Boolean
+        ) {
+            for (o in operations) {
+                val result = array.arrayTransform()
+                result.fill(o.element.elementTransform(), o.fromIndex, o.toIndex)
+                assertTrue(o.expectedResult.arrayTransform().contentEquals(result))
+            }
+        }
+
+        val array = UIntArray(5) { it.toUInt() }
+
+        val operations = listOf(
+            OperationOnRange(5u, 1, 4, uintArrayOf(0u, 5u, 5u, 5u, 4u)),
+            OperationOnRange(1u, 0, 5, uintArrayOf(1u, 1u, 1u, 1u, 1u)),
+            OperationOnRange(2u, 0, 3, uintArrayOf(2u, 2u, 2u, 3u, 4u)),
+            OperationOnRange(3u, 2, 5, uintArrayOf(0u, 1u, 3u, 3u, 3u))
+        )
+
+        test(array, UByteArray::fill, operations, UIntArray::toUByteArray, UInt::toUByte, UByteArray::contentEquals)
+        test(array, UShortArray::fill, operations, UIntArray::toUShortArray, UInt::toUShort, UShortArray::contentEquals)
+        test(array, UIntArray::fill, operations, UIntArray::copyOf, UInt::toUInt, UIntArray::contentEquals)
+        test(array, ULongArray::fill, operations, UIntArray::toULongArray, UInt::toULong, ULongArray::contentEquals)
+    }
 }
 
 

libraries/tools/binary-compatibility-validator/reference-public-api/kotlin-stdlib-runtime-merged.txt

@@ -2307,6 +2307,14 @@ public final class kotlin/collections/UArraysKt {
 	public static final fun contentToString-GBYM_sE ([B)Ljava/lang/String;
 	public static final fun contentToString-QwZRm1k ([J)Ljava/lang/String;
 	public static final fun contentToString-rL5Bavg ([S)Ljava/lang/String;
+	public static final fun fill-2fe2U9s ([IIII)V
+	public static synthetic fun fill-2fe2U9s$default ([IIIIILjava/lang/Object;)V
+	public static final fun fill-EtDCXyQ ([SSII)V
+	public static synthetic fun fill-EtDCXyQ$default ([SSIIILjava/lang/Object;)V
+	public static final fun fill-K6DWlUc ([JJII)V
+	public static synthetic fun fill-K6DWlUc$default ([JJIIILjava/lang/Object;)V
+	public static final fun fill-WpHrYlw ([BBII)V
+	public static synthetic fun fill-WpHrYlw$default ([BBIIILjava/lang/Object;)V
 	public static final fun plus-CFIt9YE ([ILjava/util/Collection;)[I
 	public static final fun plus-kzHmqpY ([JLjava/util/Collection;)[J
 	public static final fun plus-ojwP5H8 ([SLjava/util/Collection;)[S

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

@@ -1205,7 +1205,7 @@ object ArrayOps : TemplateGroupBase() {
 
     val f_fill = fn("fill(element: T, fromIndex: Int = 0, toIndex: Int = size)") {
         platforms(Platform.JVM)
-        include(InvariantArraysOfObjects, ArraysOfPrimitives)
+        include(InvariantArraysOfObjects, ArraysOfPrimitives, ArraysOfUnsigned)
     } builder {
         doc { "Fills original array with the provided value." }
         returns("Unit")
@@ -1214,6 +1214,13 @@ object ArrayOps : TemplateGroupBase() {
             java.util.Arrays.fill(this, fromIndex, toIndex, element)
             """
         }
+
+        specialFor(ArraysOfUnsigned) {
+            val signedPrimitiveName = primitive!!.name.drop(1)
+            body {
+                "storage.fill(element.to$signedPrimitiveName(), fromIndex, toIndex)"
+            }
+        }
     }
 
     val f_binarySearch = fn("binarySearch(element: T, fromIndex: Int = 0, toIndex: Int = size)") {