/** * Freezes the Promise global and prevents its reassignment. */ const deepFreeze = require('deep-freeze-strict') if ( process.env.IN_TEST !== 'true' && process.env.METAMASK_ENV !== 'test' ) { freeze(global, 'Promise') } /** * Makes a key:value pair on a target object immutable, with limitations. * The key cannot be reassigned or deleted, and the value is recursively frozen * using Object.freeze. * * Because of JavaScript language limitations, this is does not mean that the * value is completely immutable. It is, however, better than nothing. * * @param {Object} target - The target object to freeze a property on. * @param {String} key - The key to freeze. * @param {any} [value] - The value to freeze, if different from the existing value on the target. * @param {boolean} [enumerable=true] - If given a value, whether the property is enumerable. */ function freeze (target, key, value, enumerable = true) { const opts = { configurable: false, writable: false, } if (value !== undefined) { opts.value = deepFreeze(value) opts.enumerable = enumerable } else { target[key] = deepFreeze(target[key]) } Object.defineProperty(target, key, opts) }