diff --git a/src/utils/assignDeep.js b/src/utils/assignDeep.js
deleted file mode 100644
index ae545b6a5..000000000
--- a/src/utils/assignDeep.js
+++ /dev/null
@@ -1,38 +0,0 @@
-/**
- * Copyright 2018-present Facebook.
- * This source code is licensed under the MIT license found in the
- * LICENSE file in the root directory of this source tree.
- * @format
- */
-
-function isObject(val: mixed): boolean {
-  return (
-    Boolean(val) &&
-    typeof val === 'object' &&
-    Object.prototype.toString.call(val) === '[object Object]'
-  );
-}
-
-export default function assignDeep<T: Object>(
-  base: T,
-  ...reduces: Array<Object>
-): T {
-  base = Object.assign({}, base);
-
-  for (const reduce of reduces) {
-    for (const key in reduce) {
-      const baseVal = base[key];
-      const val = reduce[key];
-
-      if (isObject(val) && isObject(baseVal)) {
-        base[key] = assignDeep(baseVal, val);
-      } else if (typeof val === 'undefined') {
-        delete base[key];
-      } else {
-        base[key] = val;
-      }
-    }
-  }
-
-  return base;
-}