throw an error on non-frozen raw templates for avoiding possible brea…

…king changes in the future

CHANGELOG.md

@@ -84,6 +84,8 @@
   - Sync version of this proposal moved to Stage 3, [November 2022 TC39 meeting](https://github.com/babel/proposals/issues/85#issuecomment-1333747094)
   - Added `/actual/` namespace entries for Stage 3 proposal
 - Added [`String.dedent` stage 2 proposal](https://github.com/tc39/proposal-string-dedent)
+  - Method `String.dedent`
+  - Throws an error on non-frozen raw templates for avoiding possible breaking changes in the future, [proposal-string-dedent/75](https://github.com/tc39/proposal-string-dedent/issues/75)
 - [Compat data targets](/packages/core-js-compat#targets-option) improvements:
   - [React Native from 0.70 shipped with Hermes as the default engine.](https://reactnative.dev/blog/2022/07/08/hermes-as-the-default) However, bundled Hermes versions differ from standalone Hermes releases. So added **`react-native`** target for React Native with bundled Hermes.
   - [According to the documentation](https://developer.oculus.com/documentation/web/browser-intro/), Oculus Browser was renamed to Meta Quest Browser, so `oculus` target was renamed to **`quest`**.

babel.config.js

@@ -41,7 +41,7 @@ module.exports = {
     constantSuper: true,
     enumerableModuleMeta: true,
     iterableIsArray: true,
-    mutableTemplateObject: true,
+    mutableTemplateObject: false,
     noClassCalls: true,
     noDocumentAll: true,
     noIncompleteNsImportDetection: true,

packages/core-js/modules/esnext.string.dedent.js

@@ -1,4 +1,5 @@
 'use strict';
+var FREEZING = require('../internals/freezing');
 var $ = require('../internals/export');
 var shared = require('../internals/shared');
 var getBuiltIn = require('../internals/get-built-in');
@@ -28,6 +29,8 @@ var $Array = Array;
 var $TypeError = TypeError;
 // eslint-disable-next-line es/no-object-freeze -- safe
 var freeze = Object.freeze || Object;
+// eslint-disable-next-line es/no-object-isfrozen -- safe
+var isFrozen = Object.isFrozen;
 var min = Math.min;
 var charAt = uncurryThis(''.charAt);
 var stringSlice = uncurryThis(''.slice);
@@ -43,6 +46,8 @@ var INVALID_CLOSING_LINE = 'Invalid closing line';
 
 var dedentTemplateStringsArray = function (template) {
   var rawInput = template.raw;
+  // https://github.com/tc39/proposal-string-dedent/issues/75
+  if (FREEZING && !isFrozen(rawInput)) throw $TypeError('Raw template should be frozen');
   if (globalDedentRegistry.has(rawInput)) return globalDedentRegistry.get(rawInput);
   var raw = dedentStringsArray(rawInput);
   var cookedArr = cookStrings(raw);

tests/helpers/qunit-helpers.js

@@ -1,9 +1,14 @@
 import { DESCRIPTORS } from './constants';
 import assign from 'core-js-pure/es/object/assign';
+import defineProperties from 'core-js-pure/es/object/define-properties';
 import isIterable from 'core-js-pure/es/is-iterable';
 import ASYNC_ITERATOR from 'core-js-pure/es/symbol/async-iterator';
 import { is, arrayFromArrayLike } from './helpers';
 
+// for Babel template transform
+if (!Object.freeze) Object.freeze = Object;
+if (!DESCRIPTORS) Object.defineProperties = defineProperties;
+
 const { getOwnPropertyDescriptor } = Object;
 const { toString, propertyIsEnumerable } = Object.prototype;
 
@@ -79,7 +84,7 @@ assign(QUnit.assert, {
     this.pushResult({
       result: /native code/.test(source),
       actual: source,
-      expected: 'The function should looks like a native',
+      expected: 'The function should look like a native',
       message,
     });
   },

tests/unit-global/esnext.string.dedent.js

@@ -1,3 +1,5 @@
+const freeze = Object.freeze || Object;
+
 QUnit.test('String.dedent', assert => {
   const { cooked, dedent } = String;
   assert.isFunction(dedent);
@@ -24,8 +26,8 @@ QUnit.test('String.dedent', assert => {
    ${ ' zxc' }
   `, ' qwe\n asd\n zxc', '#3');
 
-  assert.same(dedent({ raw: ['\n  qwe\n  '] }), 'qwe', '#4');
-  assert.same(dedent({ raw: ['\n  qwe', '\n   '] }, 1), 'qwe1', '#5');
+  assert.same(dedent({ raw: freeze(['\n  qwe\n  ']) }), 'qwe', '#4');
+  assert.same(dedent({ raw: freeze(['\n  qwe', '\n   ']) }, 1), 'qwe1', '#5');
 
   assert.same(dedent(cooked)`
      qwe
@@ -40,15 +42,15 @@ QUnit.test('String.dedent', assert => {
   assert.same(dedent(tag), dedent(tag), '#7');
 
   if (typeof Symbol == 'function' && !Symbol.sham) {
-    assert.throws(() => dedent({ raw: ['\n', Symbol(), '\n'] }), TypeError, 'throws on symbol');
+    assert.throws(() => dedent({ raw: freeze(['\n', Symbol(), '\n']) }), TypeError, 'throws on symbol');
   }
 
   assert.throws(() => dedent([]), TypeError, '[]');
   assert.throws(() => dedent(['qwe']), TypeError, '[qwe]');
-  assert.throws(() => dedent({ raw: [] }), TypeError, 'empty tpl');
-  assert.throws(() => dedent({ raw: ['qwe'] }), TypeError, 'wrong start');
-  assert.throws(() => dedent({ raw: ['\n', 'qwe'] }), TypeError, 'wrong start');
-  assert.throws(() => dedent({ raw: ['\n  qwe', 5, '\n   '] }, 1, 2), TypeError, 'wrong part');
+  assert.throws(() => dedent({ raw: freeze([]) }), TypeError, 'empty tpl');
+  assert.throws(() => dedent({ raw: freeze(['qwe']) }), TypeError, 'wrong start');
+  assert.throws(() => dedent({ raw: freeze(['\n', 'qwe']) }), TypeError, 'wrong start');
+  assert.throws(() => dedent({ raw: freeze(['\n  qwe', 5, '\n   ']) }, 1, 2), TypeError, 'wrong part');
   assert.throws(() => dedent([undefined]), TypeError);
   assert.throws(() => dedent(null), TypeError);
 });

tests/unit-pure/esnext.string.dedent.js

@@ -1,6 +1,7 @@
 import Symbol from 'core-js-pure/es/symbol';
 import cooked from 'core-js-pure/full/string/cooked';
 import dedent from 'core-js-pure/full/string/dedent';
+import freeze from 'core-js-pure/es/object/freeze';
 
 QUnit.test('String.dedent', assert => {
   assert.isFunction(dedent);
@@ -25,8 +26,8 @@ QUnit.test('String.dedent', assert => {
    ${ ' zxc' }
   `, ' qwe\n asd\n zxc', '#3');
 
-  assert.same(dedent({ raw: ['\n  qwe\n  '] }), 'qwe', '#4');
-  assert.same(dedent({ raw: ['\n  qwe', '\n   '] }, 1), 'qwe1', '#5');
+  assert.same(dedent({ raw: freeze(['\n  qwe\n  ']) }), 'qwe', '#4');
+  assert.same(dedent({ raw: freeze(['\n  qwe', '\n   ']) }, 1), 'qwe1', '#5');
 
   assert.same(dedent(cooked)`
      qwe
@@ -41,15 +42,15 @@ QUnit.test('String.dedent', assert => {
   assert.same(dedent(tag), dedent(tag), '#7');
 
   if (typeof Symbol == 'function' && !Symbol.sham) {
-    assert.throws(() => dedent({ raw: ['\n', Symbol(), '\n'] }), TypeError, 'throws on symbol');
+    assert.throws(() => dedent({ raw: freeze(['\n', Symbol(), '\n']) }), TypeError, 'throws on symbol');
   }
 
   assert.throws(() => dedent([]), TypeError, '[]');
   assert.throws(() => dedent(['qwe']), TypeError, '[qwe]');
-  assert.throws(() => dedent({ raw: [] }), TypeError, 'empty tpl');
-  assert.throws(() => dedent({ raw: ['qwe'] }), TypeError, 'wrong start');
-  assert.throws(() => dedent({ raw: ['\n', 'qwe'] }), TypeError, 'wrong start');
-  assert.throws(() => dedent({ raw: ['\n  qwe', 5, '\n   '] }, 1, 2), TypeError, 'wrong part');
+  assert.throws(() => dedent({ raw: freeze([]) }), TypeError, 'empty tpl');
+  assert.throws(() => dedent({ raw: freeze(['qwe']) }), TypeError, 'wrong start');
+  assert.throws(() => dedent({ raw: freeze(['\n', 'qwe']) }), TypeError, 'wrong start');
+  assert.throws(() => dedent({ raw: freeze(['\n  qwe', 5, '\n   ']) }, 1, 2), TypeError, 'wrong part');
   assert.throws(() => dedent([undefined]), TypeError);
   assert.throws(() => dedent(null), TypeError);
 });