JS: char boxing

js/js.libraries/src/core/builtins.kt

@@ -70,4 +70,27 @@ internal fun newThrowable(message: String?, cause: Throwable?): Throwable {
     throwable.cause = cause
     throwable.name = "Throwable"
     return throwable
+}
+
+public class BoxedChar(val c: Char) : Comparable<Char> {
+    override fun equals(other: Any?): Boolean {
+        return other is BoxedChar && c == other.c
+    }
+
+    override fun hashCode(): Int {
+        return c.toInt()
+    }
+
+    override fun toString(): String {
+        return c.toString()
+    }
+
+    override fun compareTo(other: Char): Int {
+        return c - other
+    }
+
+    @JsName("valueOf")
+    public fun valueOf(): Int {
+        return js("this.c")
+    }
 }

js/js.libraries/src/core/char.kt

@@ -20,10 +20,10 @@ package kotlin.text
 public fun Char.isWhitespace(): Boolean = toString().matches("[\\s\\xA0]")
 
 @kotlin.internal.InlineOnly
-public inline fun Char.toLowerCase(): Char = asDynamic().toLowerCase()
+public inline fun Char.toLowerCase(): Char = js("String.fromCharCode")(this).toLowerCase().charCodeAt(0)
 
 @kotlin.internal.InlineOnly
-public inline fun Char.toUpperCase(): Char = asDynamic().toUpperCase()
+public inline fun Char.toUpperCase(): Char = js("String.fromCharCode")(this).toUpperCase().charCodeAt(0)
 
 /**
  * Returns `true` if this character is a Unicode high-surrogate code unit (also known as leading-surrogate code unit).

js/js.libraries/src/core/generated/_ArraysJs.kt

@@ -12944,7 +12944,7 @@ public inline fun BooleanArray.asList(): List<Boolean> {
  * Returns a [List] that wraps the original array.
  */
 public inline fun CharArray.asList(): List<Char> {
-    return this.unsafeCast<Array<Char>>().asList()
+    return this.toTypedArray().asList()
 }
 
 /**
@@ -13072,7 +13072,7 @@ public fun BooleanArray.copyOf(newSize: Int): BooleanArray {
  * Returns new array which is a copy of the original array, resized to the given [newSize].
  */
 public fun CharArray.copyOf(newSize: Int): CharArray {
-    return arrayCopyResize(this, newSize, '\u0000')
+    return arrayCopyResize(this, newSize, 0)
 }
 
 /**
@@ -13494,7 +13494,7 @@ public fun BooleanArray.toTypedArray(): Array<Boolean> {
  * Returns a *typed* object array containing all of the elements of this primitive array.
  */
 public fun CharArray.toTypedArray(): Array<Char> {
-    return copyOf().unsafeCast<Array<Char>>()
+    return Array<Char>(size, { i -> this[i] })
 }
 
 /**

js/js.libraries/src/js/conversions.js

@@ -23,7 +23,7 @@ Kotlin.toByte = function (a) {
 };
 
 Kotlin.toChar = function (a) {
-    return String.fromCharCode((((a | 0) % 65536) & 0xFFFF) << 16 >>> 16);
+    return a & 0xFFFF;
 };
 
 Kotlin.numberToLong = function (a) {
@@ -48,4 +48,15 @@ Kotlin.numberToDouble = function (a) {
 
 Kotlin.numberToChar = function (a) {
     return Kotlin.toChar(Kotlin.numberToInt(a));
-};
+};
+
+Kotlin.toBoxedChar = function (a) {
+    if (a == null) return a;
+    if (a instanceof Kotlin.BoxedChar) return a;
+    return new Kotlin.BoxedChar(a);
+};
+
+Kotlin.unboxChar = function(a) {
+    if (a == null) return a;
+    return Kotlin.toChar(a);
+};

js/js.libraries/src/js/misc.js

@@ -34,11 +34,11 @@ Kotlin.primitiveCompareTo = function (a, b) {
 };
 
 Kotlin.charInc = function (value) {
-    return String.fromCharCode(value.charCodeAt(0)+1);
+    return Kotlin.toChar(value+1);
 };
 
 Kotlin.charDec = function (value) {
-    return String.fromCharCode(value.charCodeAt(0)-1);
+    return Kotlin.toChar(value-1);
 };
 
 Kotlin.imul = Math.imul || imul;

js/js.libraries/src/js/rtti.js

@@ -128,7 +128,7 @@ Kotlin.isNumber = function (a) {
 };
 
 Kotlin.isChar = function (value) {
-    return (typeof value) == "string" && value.length == 1;
+    return value instanceof Kotlin.BoxedChar
 };
 
 Kotlin.isComparable = function (value) {