fix: TypeError: Cannot convert a Symbol value to a string (#89)

* fix: TypeError: Cannot convert a Symbol value to a string

* Update index.js

* Update index.js

Author: erezarnon

index.js

@@ -430,19 +430,15 @@ function keysEqual(leftHandOperand, rightHandOperand, keys, options) {
  * @return {Boolean} result
  */
 function objectEqual(leftHandOperand, rightHandOperand, options) {
-  var leftHandKeys = getEnumerableKeys(leftHandOperand);
-  var rightHandKeys = getEnumerableKeys(rightHandOperand);
-  var leftHandSymbols = getNonEnumerableSymbols(leftHandOperand);
-  var rightHandSymbols = getNonEnumerableSymbols(rightHandOperand);
-  if (leftHandSymbols) {
-    leftHandKeys = leftHandKeys.concat(leftHandSymbols);
-  }
-  if (rightHandSymbols) {
-    rightHandKeys = rightHandKeys.concat(rightHandSymbols);
-  }
+  var leftHandKeys = getEnumerableKeys(leftHandOperand).sort();
+  var rightHandKeys = getEnumerableKeys(rightHandOperand).sort();
+  var leftHandSymbols = getNonEnumerableSymbols(leftHandOperand).sort();
+  var rightHandSymbols = getNonEnumerableSymbols(rightHandOperand).sort();
+
+  leftHandKeys = leftHandKeys.concat(leftHandSymbols);
+  rightHandKeys = rightHandKeys.concat(rightHandSymbols);
+
   if (leftHandKeys.length && leftHandKeys.length === rightHandKeys.length) {
-    leftHandKeys.sort();
-    rightHandKeys.sort();
     if (iterableEqual(leftHandKeys, rightHandKeys) === false) {
       return false;
     }

test/index.js

@@ -416,6 +416,13 @@ describe('Generic', function () {
       var objectB = { [symb]: { [symb]: 'a' } };
       assert(eql(objectA, objectB) === false, 'eql(obj, obj) === false');
     });
+
+    it('handles objects that have both symbol keys and string keys', function () {
+      var symb = Symbol('a');
+      var objectA = { [symb]: 'a', b: 2 };
+      var objectB = { [symb]: 'a', b: 2 };
+      assert(eql(objectA, objectB) === true, 'eql(obj, obj) === true');
+    });
   });