dropdown.js

/**
 * --------------------------------------------------------------------------
 * Bootstrap (v4.3.1): dropdown.js
 * Licensed under MIT (https://github.com/twbs/bootstrap/blob/master/LICENSE)
 * --------------------------------------------------------------------------
 */

import Data from './dom/data'
import EventHandler from './dom/eventHandler'
import Manipulator from './dom/manipulator'
import Popper from 'popper.js'
import SelectorEngine from './dom/selectorEngine'
import Util from './util'

/**
 * ------------------------------------------------------------------------
 * Constants
 * ------------------------------------------------------------------------
 */

const NAME                     = 'dropdown'
const VERSION                  = '4.3.1'
const DATA_KEY                 = 'bs.dropdown'
const EVENT_KEY                = `.${DATA_KEY}`
const DATA_API_KEY             = '.data-api'
const ESCAPE_KEYCODE           = 27 // KeyboardEvent.which value for Escape (Esc) key
const SPACE_KEYCODE            = 32 // KeyboardEvent.which value for space key
const TAB_KEYCODE              = 9 // KeyboardEvent.which value for tab key
const ARROW_UP_KEYCODE         = 38 // KeyboardEvent.which value for up arrow key
const ARROW_DOWN_KEYCODE       = 40 // KeyboardEvent.which value for down arrow key
const RIGHT_MOUSE_BUTTON_WHICH = 3 // MouseEvent.which value for the right button (assuming a right-handed mouse)
const REGEXP_KEYDOWN           = new RegExp(`${ARROW_UP_KEYCODE}|${ARROW_DOWN_KEYCODE}|${ESCAPE_KEYCODE}`)

const Event = {
  HIDE             : `hide${EVENT_KEY}`,
  HIDDEN           : `hidden${EVENT_KEY}`,
  SHOW             : `show${EVENT_KEY}`,
  SHOWN            : `shown${EVENT_KEY}`,
  CLICK            : `click${EVENT_KEY}`,
  CLICK_DATA_API   : `click${EVENT_KEY}${DATA_API_KEY}`,
  KEYDOWN_DATA_API : `keydown${EVENT_KEY}${DATA_API_KEY}`,
  KEYUP_DATA_API   : `keyup${EVENT_KEY}${DATA_API_KEY}`
}

const ClassName = {
  DISABLED        : 'disabled',
  SHOW            : 'show',
  DROPUP          : 'dropup',
  DROPRIGHT       : 'dropright',
  DROPLEFT        : 'dropleft',
  MENURIGHT       : 'dropdown-menu-right',
  MENULEFT        : 'dropdown-menu-left',
  POSITION_STATIC : 'position-static'
}

const Selector = {
  DATA_TOGGLE   : '[data-toggle="dropdown"]',
  FORM_CHILD    : '.dropdown form',
  MENU          : '.dropdown-menu',
  NAVBAR_NAV    : '.navbar-nav',
  VISIBLE_ITEMS : '.dropdown-menu .dropdown-item:not(.disabled):not(:disabled)'
}

const AttachmentMap = {
  TOP       : 'top-start',
  TOPEND    : 'top-end',
  BOTTOM    : 'bottom-start',
  BOTTOMEND : 'bottom-end',
  RIGHT     : 'right-start',
  RIGHTEND  : 'right-end',