Add Array.prototype.toSorted polyfill

PiperOrigin-RevId: 810668573

Author: trevorade

externs/es6.js

@@ -1786,6 +1786,19 @@ Array.prototype.flat = function(depth) {};
  */
 Array.prototype.toReversed = function() {};
 
+/**
+ * NOTE: this is an ES2023 extern.
+ * @override
+ * @param {function(T, T): number=} compareFn A function that defines the sort
+ *     order.
+ * @return {!Array<T>}
+ * @this {!IArrayLike<T>}
+ * @template VALUE
+ * @nosideeffects
+ * @see https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/toSorted
+ */
+Array.prototype.toSorted = function(compareFn) {};
+
 /**
  * NOTE: this is an ES2023 extern.
  * @override
@@ -1932,6 +1945,18 @@ ReadonlyArray.prototype.flat = function(depth) {};
  */
 ReadonlyArray.prototype.toReversed = function() {};
 
+/**
+ * NOTE: this is an ES2023 extern.
+ * @param {function(T, T): number=} compareFn A function that defines the sort
+ *     order.
+ * @return {!Array<T>}
+ * @this {!IArrayLike<T>}
+ * @template T
+ * @nosideeffects
+ * @see https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/toSorted
+ */
+ReadonlyArray.prototype.toSorted = function(compareFn) {};
+
 /**
  * NOTE: this is an ES2023 extern.
  * @param {number} start

src/com/google/javascript/jscomp/js/es6/array.js

@@ -33,5 +33,6 @@
 'require es6/array/keys';
 'require es6/array/of';
 'require es6/array/toreversed';
+'require es6/array/tosorted';
 'require es6/array/tospliced';
 'require es6/array/values';

src/com/google/javascript/jscomp/js/es6/array/tosorted.js

@@ -0,0 +1,42 @@
+/*
+ * Copyright 2025 The Closure Compiler Authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+'require es6/array/from';
+'require util/polyfill';
+
+$jscomp.polyfill('Array.prototype.toSorted', function(orig) {
+  if (orig) return orig;
+
+  /**
+   * Returns a new array with all elements sorted.
+   *
+   * Note: This polyfill purposefully is NOT spec compliant in order to minimize
+   * code size. See skipped unit tests for specific gaps.
+   *
+   * @see https://tc39.es/ecma262/multipage/indexed-collections.html#sec-array.prototype.tosorted
+   *
+   * @param {function(T, T): number=} compareFn A function that defines the sort
+   *     order.
+   * @return {!Array<T>}
+   * @this {!IArrayLike<T>}
+   * @template T
+   */
+  var polyfill = function(compareFn) {
+    return Array.from(this).sort(compareFn);
+  };
+
+  return polyfill;
+}, 'es_next', 'es3');