[Fix] fix correct-but-spiritually-broken `RegExp.prototype[Symbol.mat…

…chAll]` implementation in node 12/chrome See https://bugs.chromium.org/p/v8/issues/detail?id=9173 / tc39/ecma262#1517
es-shims · Apr 24, 2019 · 86ed1b7 · 86ed1b7
1 parent c645e62
commit 86ed1b7
Show file tree

Hide file tree

Showing 3 changed files with 25 additions and 3 deletions.
diff --git a/polyfill-regexp-matchall.js b/polyfill-regexp-matchall.js
@@ -7,5 +7,12 @@ module.exports = function getRegExpMatchAllPolyfill() {
 	if (!hasSymbols || typeof Symbol.matchAll !== 'symbol' || typeof RegExp.prototype[Symbol.matchAll] !== 'function') {
 		return regexpMatchAll;
 	}
-	return RegExp.prototype[Symbol.matchAll];
+	try {
+		var r = /a/g;
+		Object.defineProperty(r, 'flags', { value: undefined });
+		r[Symbol.matchAll]('a');
+		return RegExp.prototype[Symbol.matchAll];
+	} catch (e) {
+		return regexpMatchAll;
+	}
 };
diff --git a/regexp-matchall.js b/regexp-matchall.js
@@ -35,7 +35,7 @@ var constructRegexWithFlags = function constructRegex(C, R) {
 	} else {
 		matcher = new C(R, flags);
 	}
-	return { flags: flags, matcher: matcher };
+	return { flags: ES.ToString(flags), matcher: matcher };
 };
 
 var regexMatchAll = function SymbolMatchAll(string) {

diff --git a/test/tests.js b/test/tests.js
@@ -106,13 +106,28 @@ module.exports = function (matchAll, regexMatchAll, t) {
 	});
 
 	t.test('#flags', function (st) {
-		st.test('without a flags property', function (s2t) {
+		st.test('with an empty string flags property', function (s2t) {
 			var str = 'aabc';
 			var regex = /[ac]/g;
 			if (define.supportsDescriptors) {
 				Object.defineProperty(regex, 'flags', { value: '' });
 			}
 			s2t.equal(regex.flags, '', 'regex has an empty string "flags" property');
+			var expectedResults = [
+				{ value: assign(['a'], groups({ index: 0, input: str })), done: false },
+				{ value: '', done: true }
+			];
+			testResults(s2t, matchAll(str, regex), expectedResults);
+			s2t.end();
+		});
+
+		st.test('without a flags property', function (s2t) {
+			var str = 'aabc';
+			var regex = /[ac]/g;
+			if (define.supportsDescriptors) {
+				Object.defineProperty(regex, 'flags', { value: undefined });
+			}
+			s2t.equal(regex.flags, undefined, 'regex has an undefined "flags" property');
 			var expectedResults = [
 				{ value: assign(['a'], groups({ index: 0, input: str })), done: false },
 				{ value: undefined, done: true }