improve Dictionary performance (#5202)

- workaround `__proto__` quirks on v8
2021-12-05 06:58:52 +00:00
parent 860aa9531b
commit b0799105c2
8 changed files with 255 additions and 221 deletions
--- a/bin/uglifyjs
+++ b/bin/uglifyjs
@@ -519,7 +519,7 @@ function read_file(path, default_value) {
 }

 function parse_js(value, options, flag) {
-    if (!options || typeof options != "object") options = {};
+    if (!options || typeof options != "object") options = Object.create(null);
    if (typeof value == "string") try {
        UglifyJS.parse(value, {
            expression: true