refactor: extract hasOwn helper

2019-09-05 20:48:14 -04:00
parent 7eed0df3c2
commit 891f21b010
5 changed files with 23 additions and 20 deletions
--- a/packages/shared/src/index.ts
+++ b/packages/shared/src/index.ts
@@ -15,6 +15,12 @@ export const extend = <T extends object, U extends object>(
  return a as any
 }

+const hasOwnProperty = Object.prototype.hasOwnProperty
+export const hasOwn = (
+  val: object,
+  key: string | symbol
+): key is keyof typeof val => hasOwnProperty.call(val, key)
+
 export const isArray = Array.isArray
 export const isFunction = (val: any): val is Function =>
  typeof val === 'function'