如何获得Object.keys（o）的正确返回类型

Question

const o1 = { f: () => 1 }
const keys1 = Object.keys(o1) // ['f']

class C { f() {} }
const c1 = new C()
const keys2 = Object.keys(c1) // []

以下ObjectKeys返回['f']的{​​{1}}。这是我的问题。

class C

我知道TypeScript永远不会知道属性是否被隐藏。但是我想摆脱那些我们知道对于type ObjectKeys<T> = T extends object ? { [Key in keyof T]: Key }[keyof T] : never function objectKeys<T>(o: T) { if (o === undefined || o === null) { return [] } return (Object.keys(o) as any) as ReadonlyArray<ObjectKeys<T>> } const keys3 = objectKeys(o1) // Return type is ['f'] const keys4 = objectKeys(c1) // Return type is ['f'], but the value is [] 不可见的类方法名称。