bootstrap-vue/src/utils/object.js

BootstrapVue provides one of the most comprehensive implementations of Bootstrap 4 components and grid system for Vue.js and with extensive and automated WAI-ARIA accessibility markup.

/**
 * Aliasing Object[method] allows the minifier to shorten methods to a single character variable,
 * as well as giving BV a chance to inject polyfills.
 * As long as we avoid
 * - import * as Object from "utils/object"
 * all unused exports should be removed by tree-shaking.
 */

// @link https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object/assign
if (typeof Object.assign !== 'function') {
  Object.assign = function (target, varArgs) {
    // .length of function is 2

    if (target == null) {
      // TypeError if undefined or null
      throw new TypeError('Cannot convert undefined or null to object')
    }

    let to = Object(target)

    for (let index = 1; index < arguments.length; index++) {
      const nextSource = arguments[index]

      if (nextSource != null) {
        // Skip over if undefined or null
        for (const nextKey in nextSource) {
          // Avoid bugs when hasOwnProperty is shadowed
          if (Object.prototype.hasOwnProperty.call(nextSource, nextKey)) {
            to[nextKey] = nextSource[nextKey]
          }
        }
      }
    }
    return to
  }
}

// @link https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object/is#Polyfill
if (!Object.is) {
  Object.is = function (x, y) {
    // SameValue algorithm
    if (x === y) { // Steps 1-5, 7-10
      // Steps 6.b-6.e: +0 != -0
      return x !== 0 || 1 / x === 1 / y
    } else {
      // Step 6.a: NaN == NaN
      // eslint-disable-next-line no-self-compare
      return x !== x && y !== y
    }
  }
}

export const assign = Object.assign
export const getOwnPropertyNames = Object.getOwnPropertyNames
export const keys = Object.keys
export const defineProperties = Object.defineProperties
export const defineProperty = Object.defineProperty
export const freeze = Object.freeze
export const getOwnPropertyDescriptor = Object.getOwnPropertyDescriptor
export const getOwnPropertySymbols = Object.getOwnPropertySymbols
export const getPrototypeOf = Object.getPrototypeOf
export const create = Object.create
export const isFrozen = Object.isFrozen
export const is = Object.is

export function readonlyDescriptor () {
  return { enumerable: true, configurable: false, writable: false }
}