const {toString} = Object.prototype; const isError = value => toString.call(value) === '[object Error]'; export class PresentableError extends Error { constructor(message, {cause} = {}) { super(); if (message instanceof PresentableError) { return message; // eslint-disable-line no-constructor-return } if (typeof message !== 'string') { throw new TypeError('Message required.'); } this.name = 'PresentableError'; this.message = message; this.cause = cause; } get isPresentable() { return true; } } export function isPresentableError(value) { return value && isError(value) && value.isPresentable === true; } export function makePresentableError(error) { if (!isError(error)) { throw new TypeError('The value is not an error.'); } if (isPresentableError(error)) { return; } if (!Object.isExtensible(error)) { throw new Error('The error is non-extensible and cannot be edited.'); } Object.defineProperty(error, 'isPresentable', {value: true}); }