improve false positive detection in `ufuzz` (#3982)

diff --git a/test/ufuzz/index.js b/test/ufuzz/index.js
index b8a09c0..006b4ca 100644 (file)
--- a/test/ufuzz/index.js
+++ b/test/ufuzz/index.js
@@ -1167,6 +1167,10 @@ function log(options) {
     }
 }
 
+function sort_globals(code) {
+    return "var " + sandbox.run_code("throw Object.keys(this).sort();" + code).join(",") + ";" + code;
+}
+
 function fuzzy_match(original, uglified) {
     uglified = uglified.split(" ");
     var i = uglified.length;
@@ -1245,14 +1249,6 @@ var fallback_options = [ JSON.stringify({
     mangle: false
 }) ];
 var minify_options = require("./options.json").map(JSON.stringify);
-var sort_globals = [
-    "Object.keys(this).sort().forEach(function(name) {",
-    "    var value = this[name];",
-    "    delete this[name];",
-    "    this[name] = value;",
-    "});",
-    "",
-].join("\n");
 var original_code, original_result, errored;
 var uglify_code, uglify_result, ok;
 for (var round = 1; round <= num_iterations; round++) {
@@ -1274,7 +1270,7 @@ for (var round = 1; round <= num_iterations; round++) {
             ok = sandbox.same_stdout(original_result, uglify_result);
             // ignore declaration order of global variables
             if (!ok && !toplevel) {
-                ok = sandbox.same_stdout(sandbox.run_code(sort_globals + original_code), sandbox.run_code(sort_globals + uglify_code));
+                ok = sandbox.same_stdout(sandbox.run_code(sort_globals(original_code)), sandbox.run_code(sort_globals(uglify_code)));
             }
             // ignore numerical imprecision caused by `unsafe_math`
             if (!ok && typeof uglify_result == "string" && o.compress && o.compress.unsafe_math) {