diff --git a/src/utils/kindOf.js b/src/utils/kindOf.js
index c5395a1df6..9c5a0ae727 100644
--- a/src/utils/kindOf.js
+++ b/src/utils/kindOf.js
@@ -1,68 +1,68 @@
-export function kindOf(val) {
-  let typeOfVal = typeof val
+// Inlined / shortened version of `kindOf` from https://github.com/jonschlinkert/kind-of
+function miniKindOf(val) {
+  if (val === void 0) return 'undefined'
+  if (val === null) return 'null'
 
-  if (process.env.NODE_ENV !== 'production') {
-    // Inlined / shortened version of `kindOf` from https://github.com/jonschlinkert/kind-of
-    function miniKindOf(val) {
-      if (val === void 0) return 'undefined'
-      if (val === null) return 'null'
+  const type = typeof val
+  switch (type) {
+    case 'boolean':
+    case 'string':
+    case 'number':
+    case 'symbol':
+    case 'function': {
+      return type
+    }
+    default:
+      break
+  }
 
-      const type = typeof val
-      switch (type) {
-        case 'boolean':
-        case 'string':
-        case 'number':
-        case 'symbol':
-        case 'function': {
-          return type
-        }
-        default:
-          break
-      }
+  if (Array.isArray(val)) return 'array'
+  if (isDate(val)) return 'date'
+  if (isError(val)) return 'error'
 
-      if (Array.isArray(val)) return 'array'
-      if (isDate(val)) return 'date'
-      if (isError(val)) return 'error'
+  const constructorName = ctorName(val)
+  switch (constructorName) {
+    case 'Symbol':
+    case 'Promise':
+    case 'WeakMap':
+    case 'WeakSet':
+    case 'Map':
+    case 'Set':
+      return constructorName
+    default:
+      break
+  }
 
-      const constructorName = ctorName(val)
-      switch (constructorName) {
-        case 'Symbol':
-        case 'Promise':
-        case 'WeakMap':
-        case 'WeakSet':
-        case 'Map':
-        case 'Set':
-          return constructorName
-        default:
-          break
-      }
+  // other
+  return type.slice(8, -1).toLowerCase().replace(/\s/g, '')
+}
 
-      // other
-      return type.slice(8, -1).toLowerCase().replace(/\s/g, '')
-    }
+function ctorName(val) {
+  return typeof val.constructor === 'function' ? val.constructor.name : null
+}
 
-    function ctorName(val) {
-      return typeof val.constructor === 'function' ? val.constructor.name : null
-    }
+function isError(val) {
+  return (
+    val instanceof Error ||
+    (typeof val.message === 'string' &&
+      val.constructor &&
+      typeof val.constructor.stackTraceLimit === 'number')
+  )
+}
 
-    function isError(val) {
-      return (
-        val instanceof Error ||
-        (typeof val.message === 'string' &&
-          val.constructor &&
-          typeof val.constructor.stackTraceLimit === 'number')
-      )
-    }
+function isDate(val) {
+  if (val instanceof Date) return true
+  return (
+    typeof val.toDateString === 'function' &&
+    typeof val.getDate === 'function' &&
+    typeof val.setDate === 'function'
+  )
+}
 
-    function isDate(val) {
-      if (val instanceof Date) return true
-      return (
-        typeof val.toDateString === 'function' &&
-        typeof val.getDate === 'function' &&
-        typeof val.setDate === 'function'
-      )
-    }
+export function kindOf(val) {
+  let typeOfVal = typeof val
 
+  if (process.env.NODE_ENV !== 'production') {
     typeOfVal = miniKindOf(val)
   }