diff --git a/test/test.js b/test/test.js
index 7fe9c179e..284c6ea32 100644
--- a/test/test.js
+++ b/test/test.js
@@ -2954,9 +2954,7 @@
 
       while (++index < length) {
         var other = array[index];
-        if (other === value ||
-            (_.isObject(value) && other instanceof Foo) ||
-            (other === 'x' && /[13]/.test(value))) {
+        if (other === value || (value instanceof Foo && other instanceof Foo)) {
           return index;
         }
       }
@@ -3001,17 +2999,6 @@
       }
     });
 
-    test('`_.omit` should work with a custom `_.indexOf` method', 1, function() {
-      if (!isModularize) {
-        _.indexOf = custom;
-        deepEqual(_.omit(array, ['x']), { '0': 1, '2': 3 });
-        _.indexOf = indexOf;
-      }
-      else {
-        skipTest();
-      }
-    });
-
     test('`_.uniq` should work with a custom `_.indexOf` method', 2, function() {
       if (!isModularize) {
         _.indexOf = custom;