// merged from next.js // https://github.com/vercel/next.js/blob/e657741b9908cf0044aaef959c0c4defb19ed6d8/packages/next/src/lib/is-error.ts // https://github.com/vercel/next.js/blob/e657741b9908cf0044aaef959c0c4defb19ed6d8/packages/next/src/shared/lib/is-plain-object.ts export default function isError(err: unknown): err is Error { return ( typeof err === 'object' && err !== null && 'name' in err && 'message' in err ) } export function getProperError(err: unknown): Error { if (isError(err)) { return err } if (process.env.NODE_ENV === 'development') { // Provide a better error message for cases where `throw undefined` // is called in development if (typeof err === 'undefined') { return new Error('`undefined` was thrown instead of a real error') } if (err === null) { return new Error('`null` was thrown instead of a real error') } } return new Error(isPlainObject(err) ? JSON.stringify(err) : err + '') } function getObjectClassLabel(value: any): string { return Object.prototype.toString.call(value) } function isPlainObject(value: any): boolean { if (getObjectClassLabel(value) !== '[object Object]') { return false } const prototype = Object.getPrototypeOf(value) /** * this used to be previously: * * `return prototype === null || prototype === Object.prototype` * * but Edge Runtime expose Object from vm, being that kind of type-checking wrongly fail. * * It was changed to the current implementation since it's resilient to serialization. */ return prototype === null || prototype.hasOwnProperty('isPrototypeOf') }