Format symbols

harness/compareArray.js

@@ -26,6 +26,10 @@ function compareArray(a, b) {
 }
 
 assert.compareArray = function(actual, expected, message) {
+  function formatArray(array) {
+    return '[' + array.map(String).join(', ') + ']';
+  }
+
   assert(compareArray(actual, expected),
-         'Expected [' + actual.join(', ') + '] and [' + expected.join(', ') + '] to have the same contents. ' + message);
+         'Expected ' + formatArray(actual) + ' and ' + formatArray(expected) + ' to have the same contents. ' + message);
 };

test/harness/compare-array-symbol.js

@@ -0,0 +1,23 @@
+// Copyright (C) 2019 Alexey Shvayka. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+
+/*---
+description: >
+  compareArray correctly formats Symbols in error message.
+includes: [compareArray.js]
+features: [Symbol]
+---*/
+
+var threw = false;
+
+try {
+	assert.compareArray([Symbol()], [Symbol('desc')]);
+} catch (err) {
+  threw = true;
+
+  assert.sameValue(err.constructor, Test262Error);
+  assert(err.message.indexOf('[Symbol()]') !== -1);
+  assert(err.message.indexOf('[Symbol(desc)]') !== -1);
+}
+
+assert(threw);