js/src/dropdown.js - external/github.com/twbs/bootstrap - Git at Google

 /**
  * --------------------------------------------------------------------------
  * Bootstrap (v4.6.2): dropdown.js
  * Licensed under MIT (https://github.com/twbs/bootstrap/blob/main/LICENSE)
  * --------------------------------------------------------------------------
  */

 import $ from 'jquery'
 import Popper from 'popper.js'
 import Util from './util'

 /**
  * Constants
  */

 const NAME = 'dropdown'
 const VERSION = '4.6.2'
 const DATA_KEY = 'bs.dropdown'
 const EVENT_KEY = `.${DATA_KEY}`
 const DATA_API_KEY = '.data-api'
 const JQUERY_NO_CONFLICT = $.fn[NAME]
 const ESCAPE_KEYCODE = 27 // KeyboardEvent.which value for Escape (Esc) key
 const SPACE_KEYCODE = 32 // KeyboardEvent.which value for space key
 const TAB_KEYCODE = 9 // KeyboardEvent.which value for tab key
 const ARROW_UP_KEYCODE = 38 // KeyboardEvent.which value for up arrow key
 const ARROW_DOWN_KEYCODE = 40 // KeyboardEvent.which value for down arrow key
 const RIGHT_MOUSE_BUTTON_WHICH = 3 // MouseEvent.which value for the right button (assuming a right-handed mouse)
 const REGEXP_KEYDOWN = new RegExp(`${ARROW_UP_KEYCODE}|${ARROW_DOWN_KEYCODE}|${ESCAPE_KEYCODE}`)

 const CLASS_NAME_DISABLED = 'disabled'
 const CLASS_NAME_SHOW = 'show'
 const CLASS_NAME_DROPUP = 'dropup'
 const CLASS_NAME_DROPRIGHT = 'dropright'
 const CLASS_NAME_DROPLEFT = 'dropleft'
 const CLASS_NAME_MENURIGHT = 'dropdown-menu-right'
 const CLASS_NAME_POSITION_STATIC = 'position-static'

 const EVENT_HIDE = `hide${EVENT_KEY}`
 const EVENT_HIDDEN = `hidden${EVENT_KEY}`
 const EVENT_SHOW = `show${EVENT_KEY}`
 const EVENT_SHOWN = `shown${EVENT_KEY}`
 const EVENT_CLICK = `click${EVENT_KEY}`
 const EVENT_CLICK_DATA_API = `click${EVENT_KEY}${DATA_API_KEY}`
 const EVENT_KEYDOWN_DATA_API = `keydown${EVENT_KEY}${DATA_API_KEY}`
 const EVENT_KEYUP_DATA_API = `keyup${EVENT_KEY}${DATA_API_KEY}`

 const SELECTOR_DATA_TOGGLE = '[data-toggle="dropdown"]'
 const SELECTOR_FORM_CHILD = '.dropdown form'
 const SELECTOR_MENU = '.dropdown-menu'
 const SELECTOR_NAVBAR_NAV = '.navbar-nav'
 const SELECTOR_VISIBLE_ITEMS = '.dropdown-menu .dropdown-item:not(.disabled):not(:disabled)'

 const PLACEMENT_TOP = 'top-start'
 const PLACEMENT_TOPEND = 'top-end'
 const PLACEMENT_BOTTOM = 'bottom-start'
 const PLACEMENT_BOTTOMEND = 'bottom-end'
 const PLACEMENT_RIGHT = 'right-start'
 const PLACEMENT_LEFT = 'left-start'

 const Default = {
   offset: 0,
   flip: true,
   boundary: 'scrollParent',
   reference: 'toggle',
   display: 'dynamic',
   popperConfig: null
 }

 const DefaultType = {
   offset: '(number|string|function)',
   flip: 'boolean',
   boundary: '(string|element)',
   reference: '(string|element)',
   display: 'string',
   popperConfig: '(null|object)'
 }

 /**
  * Class definition
  */

 class Dropdown {
   constructor(element, config) {
     this._element = element
     this._popper = null
     this._config = this._getConfig(config)
     this._menu = this._getMenuElement()
     this._inNavbar = this._detectNavbar()

     this._addEventListeners()
   }

   // Getters
   static get VERSION() {
     return VERSION
   }

   static get Default() {
     return Default
   }

   static get DefaultType() {
     return DefaultType
   }

   // Public
   toggle() {
     if (this._element.disabled || $(this._element).hasClass(CLASS_NAME_DISABLED)) {
       return
     }

     const isActive = $(this._menu).hasClass(CLASS_NAME_SHOW)

     Dropdown._clearMenus()

     if (isActive) {
       return
     }

     this.show(true)
   }

   show(usePopper = false) {
     if (this._element.disabled || $(this._element).hasClass(CLASS_NAME_DISABLED) || $(this._menu).hasClass(CLASS_NAME_SHOW)) {
       return
     }

     const relatedTarget = {
       relatedTarget: this._element
     }
     const showEvent = $.Event(EVENT_SHOW, relatedTarget)
     const parent = Dropdown._getParentFromElement(this._element)

     $(parent).trigger(showEvent)

     if (showEvent.isDefaultPrevented()) {
       return
     }

     // Totally disable Popper for Dropdowns in Navbar
     if (!this._inNavbar && usePopper) {
       // Check for Popper dependency
       if (typeof Popper === 'undefined') {
         throw new TypeError('Bootstrap\'s dropdowns require Popper (https://popper.js.org)')
       }

       let referenceElement = this._element

       if (this._config.reference === 'parent') {
         referenceElement = parent
       } else if (Util.isElement(this._config.reference)) {
         referenceElement = this._config.reference

         // Check if it's jQuery element
         if (typeof this._config.reference.jquery !== 'undefined') {
           referenceElement = this._config.reference[0]
         }
       }

       // If boundary is not `scrollParent`, then set position to `static`
       // to allow the menu to "escape" the scroll parent's boundaries
       // https://github.com/twbs/bootstrap/issues/24251
       if (this._config.boundary !== 'scrollParent') {
         $(parent).addClass(CLASS_NAME_POSITION_STATIC)
       }

       this._popper = new Popper(referenceElement, this._menu, this._getPopperConfig())
     }

     // If this is a touch-enabled device we add extra
     // empty mouseover listeners to the body's immediate children;
     // only needed because of broken event delegation on iOS
     // https://www.quirksmode.org/blog/archives/2014/02/mouse_event_bub.html
     if ('ontouchstart' in document.documentElement &&
         $(parent).closest(SELECTOR_NAVBAR_NAV).length === 0) {
       $(document.body).children().on('mouseover', null, $.noop)
     }

     this._element.focus()
     this._element.setAttribute('aria-expanded', true)

     $(this._menu).toggleClass(CLASS_NAME_SHOW)
     $(parent)
       .toggleClass(CLASS_NAME_SHOW)
       .trigger($.Event(EVENT_SHOWN, relatedTarget))
   }

   hide() {
     if (this._element.disabled || $(this._element).hasClass(CLASS_NAME_DISABLED) || !$(this._menu).hasClass(CLASS_NAME_SHOW)) {
       return
     }

     const relatedTarget = {
       relatedTarget: this._element
     }
     const hideEvent = $.Event(EVENT_HIDE, relatedTarget)
     const parent = Dropdown._getParentFromElement(this._element)

     $(parent).trigger(hideEvent)

     if (hideEvent.isDefaultPrevented()) {
       return
     }

     if (this._popper) {
       this._popper.destroy()
     }

     $(this._menu).toggleClass(CLASS_NAME_SHOW)
     $(parent)
       .toggleClass(CLASS_NAME_SHOW)
       .trigger($.Event(EVENT_HIDDEN, relatedTarget))
   }

   dispose() {
     $.removeData(this._element, DATA_KEY)
     $(this._element).off(EVENT_KEY)
     this._element = null
     this._menu = null
     if (this._popper !== null) {
       this._popper.destroy()
       this._popper = null
     }
   }

   update() {
     this._inNavbar = this._detectNavbar()
     if (this._popper !== null) {
       this._popper.scheduleUpdate()
     }
   }

   // Private
   _addEventListeners() {
     $(this._element).on(EVENT_CLICK, event => {
       event.preventDefault()
       event.stopPropagation()
       this.toggle()
     })
   }

   _getConfig(config) {
     config = {
       ...this.constructor.Default,
       ...$(this._element).data(),
       ...config
     }

     Util.typeCheckConfig(
       NAME,
       config,
       this.constructor.DefaultType
     )

     return config
   }

   _getMenuElement() {
     if (!this._menu) {
       const parent = Dropdown._getParentFromElement(this._element)

       if (parent) {
         this._menu = parent.querySelector(SELECTOR_MENU)
       }
     }

     return this._menu
   }

   _getPlacement() {
     const $parentDropdown = $(this._element.parentNode)
     let placement = PLACEMENT_BOTTOM

     // Handle dropup
     if ($parentDropdown.hasClass(CLASS_NAME_DROPUP)) {
       placement = $(this._menu).hasClass(CLASS_NAME_MENURIGHT) ?
         PLACEMENT_TOPEND :
         PLACEMENT_TOP
     } else if ($parentDropdown.hasClass(CLASS_NAME_DROPRIGHT)) {
       placement = PLACEMENT_RIGHT
     } else if ($parentDropdown.hasClass(CLASS_NAME_DROPLEFT)) {
       placement = PLACEMENT_LEFT
     } else if ($(this._menu).hasClass(CLASS_NAME_MENURIGHT)) {
       placement = PLACEMENT_BOTTOMEND
     }

     return placement
   }

   _detectNavbar() {
     return $(this._element).closest('.navbar').length > 0
   }

   _getOffset() {
     const offset = {}

     if (typeof this._config.offset === 'function') {
       offset.fn = data => {
         data.offsets = {
           ...data.offsets,
           ...this._config.offset(data.offsets, this._element)
         }

         return data
       }
     } else {
       offset.offset = this._config.offset
     }

     return offset
   }

   _getPopperConfig() {
     const popperConfig = {
       placement: this._getPlacement(),
       modifiers: {
         offset: this._getOffset(),
         flip: {
           enabled: this._config.flip
         },
         preventOverflow: {
           boundariesElement: this._config.boundary
         }
       }
     }

     // Disable Popper if we have a static display
     if (this._config.display === 'static') {
       popperConfig.modifiers.applyStyle = {
         enabled: false
       }
     }

     return {
       ...popperConfig,
       ...this._config.popperConfig
     }
   }

   // Static
   static _jQueryInterface(config) {
     return this.each(function () {
       let data = $(this).data(DATA_KEY)
       const _config = typeof config === 'object' ? config : null

       if (!data) {
         data = new Dropdown(this, _config)
         $(this).data(DATA_KEY, data)
       }

       if (typeof config === 'string') {
         if (typeof data[config] === 'undefined') {
           throw new TypeError(`No method named "${config}"`)
         }

         data[config]()
       }
     })
   }

   static _clearMenus(event) {
     if (event && (event.which === RIGHT_MOUSE_BUTTON_WHICH ||
       event.type === 'keyup' && event.which !== TAB_KEYCODE)) {
       return
     }

     const toggles = [].slice.call(document.querySelectorAll(SELECTOR_DATA_TOGGLE))

     for (let i = 0, len = toggles.length; i < len; i++) {
       const parent = Dropdown._getParentFromElement(toggles[i])
       const context = $(toggles[i]).data(DATA_KEY)
       const relatedTarget = {
         relatedTarget: toggles[i]
       }

       if (event && event.type === 'click') {
         relatedTarget.clickEvent = event
       }

       if (!context) {
         continue
       }

       const dropdownMenu = context._menu
       if (!$(parent).hasClass(CLASS_NAME_SHOW)) {
         continue
       }

       if (event && (event.type === 'click' &&
           /input|textarea/i.test(event.target.tagName) || event.type === 'keyup' && event.which === TAB_KEYCODE) &&
           $.contains(parent, event.target)) {
         continue
       }

       const hideEvent = $.Event(EVENT_HIDE, relatedTarget)
       $(parent).trigger(hideEvent)
       if (hideEvent.isDefaultPrevented()) {
         continue
       }

       // If this is a touch-enabled device we remove the extra
       // empty mouseover listeners we added for iOS support
       if ('ontouchstart' in document.documentElement) {
         $(document.body).children().off('mouseover', null, $.noop)
       }

       toggles[i].setAttribute('aria-expanded', 'false')

       if (context._popper) {
         context._popper.destroy()
       }

       $(dropdownMenu).removeClass(CLASS_NAME_SHOW)
       $(parent)
         .removeClass(CLASS_NAME_SHOW)
         .trigger($.Event(EVENT_HIDDEN, relatedTarget))
     }
   }

   static _getParentFromElement(element) {
     let parent
     const selector = Util.getSelectorFromElement(element)

     if (selector) {
       parent = document.querySelector(selector)
     }

     return parent || element.parentNode
   }

   // eslint-disable-next-line complexity
   static _dataApiKeydownHandler(event) {
     // If not input/textarea:
     //  - And not a key in REGEXP_KEYDOWN => not a dropdown command
     // If input/textarea:
     //  - If space key => not a dropdown command
     //  - If key is other than escape
     //    - If key is not up or down => not a dropdown command
     //    - If trigger inside the menu => not a dropdown command
     if (/input|textarea/i.test(event.target.tagName) ?
       event.which === SPACE_KEYCODE || event.which !== ESCAPE_KEYCODE &&
       (event.which !== ARROW_DOWN_KEYCODE && event.which !== ARROW_UP_KEYCODE ||
         $(event.target).closest(SELECTOR_MENU).length) : !REGEXP_KEYDOWN.test(event.which)) {
       return
     }

     if (this.disabled || $(this).hasClass(CLASS_NAME_DISABLED)) {
       return
     }

     const parent = Dropdown._getParentFromElement(this)
     const isActive = $(parent).hasClass(CLASS_NAME_SHOW)

     if (!isActive && event.which === ESCAPE_KEYCODE) {
       return
     }

     event.preventDefault()
     event.stopPropagation()

     if (!isActive || (event.which === ESCAPE_KEYCODE || event.which === SPACE_KEYCODE)) {
       if (event.which === ESCAPE_KEYCODE) {
         $(parent.querySelector(SELECTOR_DATA_TOGGLE)).trigger('focus')
       }

       $(this).trigger('click')
       return
     }

     const items = [].slice.call(parent.querySelectorAll(SELECTOR_VISIBLE_ITEMS))
       .filter(item => $(item).is(':visible'))

     if (items.length === 0) {
       return
     }

     let index = items.indexOf(event.target)

     if (event.which === ARROW_UP_KEYCODE && index > 0) { // Up
       index--
     }

     if (event.which === ARROW_DOWN_KEYCODE && index < items.length - 1) { // Down
       index++
     }

     if (index < 0) {
       index = 0
     }

     items[index].focus()
   }
 }

 /**
  * Data API implementation
  */

 $(document)
   .on(EVENT_KEYDOWN_DATA_API, SELECTOR_DATA_TOGGLE, Dropdown._dataApiKeydownHandler)
   .on(EVENT_KEYDOWN_DATA_API, SELECTOR_MENU, Dropdown._dataApiKeydownHandler)
   .on(`${EVENT_CLICK_DATA_API} ${EVENT_KEYUP_DATA_API}`, Dropdown._clearMenus)
   .on(EVENT_CLICK_DATA_API, SELECTOR_DATA_TOGGLE, function (event) {
     event.preventDefault()
     event.stopPropagation()
     Dropdown._jQueryInterface.call($(this), 'toggle')
   })
   .on(EVENT_CLICK_DATA_API, SELECTOR_FORM_CHILD, e => {
     e.stopPropagation()
   })

 /**
  * jQuery
  */

 $.fn[NAME] = Dropdown._jQueryInterface
 $.fn[NAME].Constructor = Dropdown
 $.fn[NAME].noConflict = () => {
   $.fn[NAME] = JQUERY_NO_CONFLICT
   return Dropdown._jQueryInterface
 }

 export default Dropdown
	/**
	* --------------------------------------------------------------------------
	* Bootstrap (v4.6.2): dropdown.js
	* Licensed under MIT (https://github.com/twbs/bootstrap/blob/main/LICENSE)
	* --------------------------------------------------------------------------
	*/

	import $ from 'jquery'
	import Popper from 'popper.js'
	import Util from './util'

	/**
	* Constants
	*/

	const NAME = 'dropdown'
	const VERSION = '4.6.2'
	const DATA_KEY = 'bs.dropdown'
	const EVENT_KEY = `.${DATA_KEY}`
	const DATA_API_KEY = '.data-api'
	const JQUERY_NO_CONFLICT = $.fn[NAME]
	const ESCAPE_KEYCODE = 27 // KeyboardEvent.which value for Escape (Esc) key
	const SPACE_KEYCODE = 32 // KeyboardEvent.which value for space key
	const TAB_KEYCODE = 9 // KeyboardEvent.which value for tab key
	const ARROW_UP_KEYCODE = 38 // KeyboardEvent.which value for up arrow key
	const ARROW_DOWN_KEYCODE = 40 // KeyboardEvent.which value for down arrow key
	const RIGHT_MOUSE_BUTTON_WHICH = 3 // MouseEvent.which value for the right button (assuming a right-handed mouse)
	const REGEXP_KEYDOWN = new RegExp(`${ARROW_UP_KEYCODE}\|${ARROW_DOWN_KEYCODE}\|${ESCAPE_KEYCODE}`)

	const CLASS_NAME_DISABLED = 'disabled'
	const CLASS_NAME_SHOW = 'show'
	const CLASS_NAME_DROPUP = 'dropup'
	const CLASS_NAME_DROPRIGHT = 'dropright'
	const CLASS_NAME_DROPLEFT = 'dropleft'
	const CLASS_NAME_MENURIGHT = 'dropdown-menu-right'
	const CLASS_NAME_POSITION_STATIC = 'position-static'

	const EVENT_HIDE = `hide${EVENT_KEY}`
	const EVENT_HIDDEN = `hidden${EVENT_KEY}`
	const EVENT_SHOW = `show${EVENT_KEY}`
	const EVENT_SHOWN = `shown${EVENT_KEY}`
	const EVENT_CLICK = `click${EVENT_KEY}`
	const EVENT_CLICK_DATA_API = `click${EVENT_KEY}${DATA_API_KEY}`
	const EVENT_KEYDOWN_DATA_API = `keydown${EVENT_KEY}${DATA_API_KEY}`
	const EVENT_KEYUP_DATA_API = `keyup${EVENT_KEY}${DATA_API_KEY}`

	const SELECTOR_DATA_TOGGLE = '[data-toggle="dropdown"]'
	const SELECTOR_FORM_CHILD = '.dropdown form'
	const SELECTOR_MENU = '.dropdown-menu'
	const SELECTOR_NAVBAR_NAV = '.navbar-nav'
	const SELECTOR_VISIBLE_ITEMS = '.dropdown-menu .dropdown-item:not(.disabled):not(:disabled)'

	const PLACEMENT_TOP = 'top-start'
	const PLACEMENT_TOPEND = 'top-end'
	const PLACEMENT_BOTTOM = 'bottom-start'
	const PLACEMENT_BOTTOMEND = 'bottom-end'
	const PLACEMENT_RIGHT = 'right-start'
	const PLACEMENT_LEFT = 'left-start'

	const Default = {
	offset: 0,
	flip: true,
	boundary: 'scrollParent',
	reference: 'toggle',
	display: 'dynamic',
	popperConfig: null
	}

	const DefaultType = {
	offset: '(number\|string\|function)',
	flip: 'boolean',
	boundary: '(string\|element)',
	reference: '(string\|element)',
	display: 'string',
	popperConfig: '(null\|object)'
	}

	/**
	* Class definition
	*/

	class Dropdown {
	constructor(element, config) {
	this._element = element
	this._popper = null
	this._config = this._getConfig(config)
	this._menu = this._getMenuElement()
	this._inNavbar = this._detectNavbar()

	this._addEventListeners()
	}

	// Getters
	static get VERSION() {
	return VERSION
	}

	static get Default() {
	return Default
	}

	static get DefaultType() {
	return DefaultType
	}

	// Public
	toggle() {
	if (this._element.disabled \|\| $(this._element).hasClass(CLASS_NAME_DISABLED)) {
	return
	}

	const isActive = $(this._menu).hasClass(CLASS_NAME_SHOW)

	Dropdown._clearMenus()

	if (isActive) {
	return
	}

	this.show(true)
	}

	show(usePopper = false) {
	if (this._element.disabled \|\| $(this._element).hasClass(CLASS_NAME_DISABLED) \|\| $(this._menu).hasClass(CLASS_NAME_SHOW)) {
	return
	}

	const relatedTarget = {
	relatedTarget: this._element
	}
	const showEvent = $.Event(EVENT_SHOW, relatedTarget)
	const parent = Dropdown._getParentFromElement(this._element)

	$(parent).trigger(showEvent)

	if (showEvent.isDefaultPrevented()) {
	return
	}

	// Totally disable Popper for Dropdowns in Navbar
	if (!this._inNavbar && usePopper) {
	// Check for Popper dependency
	if (typeof Popper === 'undefined') {
	throw new TypeError('Bootstrap\'s dropdowns require Popper (https://popper.js.org)')
	}

	let referenceElement = this._element

	if (this._config.reference === 'parent') {
	referenceElement = parent
	} else if (Util.isElement(this._config.reference)) {
	referenceElement = this._config.reference

	// Check if it's jQuery element
	if (typeof this._config.reference.jquery !== 'undefined') {
	referenceElement = this._config.reference[0]
	}
	}

	// If boundary is not `scrollParent`, then set position to `static`
	// to allow the menu to "escape" the scroll parent's boundaries
	// https://github.com/twbs/bootstrap/issues/24251
	if (this._config.boundary !== 'scrollParent') {
	$(parent).addClass(CLASS_NAME_POSITION_STATIC)
	}

	this._popper = new Popper(referenceElement, this._menu, this._getPopperConfig())
	}

	// If this is a touch-enabled device we add extra
	// empty mouseover listeners to the body's immediate children;
	// only needed because of broken event delegation on iOS
	// https://www.quirksmode.org/blog/archives/2014/02/mouse_event_bub.html
	if ('ontouchstart' in document.documentElement &&
	$(parent).closest(SELECTOR_NAVBAR_NAV).length === 0) {
	$(document.body).children().on('mouseover', null, $.noop)
	}

	this._element.focus()
	this._element.setAttribute('aria-expanded', true)

	$(this._menu).toggleClass(CLASS_NAME_SHOW)
	$(parent)
	.toggleClass(CLASS_NAME_SHOW)
	.trigger($.Event(EVENT_SHOWN, relatedTarget))
	}

	hide() {
	if (this._element.disabled \|\| $(this._element).hasClass(CLASS_NAME_DISABLED) \|\| !$(this._menu).hasClass(CLASS_NAME_SHOW)) {
	return
	}

	const relatedTarget = {
	relatedTarget: this._element
	}
	const hideEvent = $.Event(EVENT_HIDE, relatedTarget)
	const parent = Dropdown._getParentFromElement(this._element)

	$(parent).trigger(hideEvent)

	if (hideEvent.isDefaultPrevented()) {
	return
	}

	if (this._popper) {
	this._popper.destroy()
	}

	$(this._menu).toggleClass(CLASS_NAME_SHOW)
	$(parent)
	.toggleClass(CLASS_NAME_SHOW)
	.trigger($.Event(EVENT_HIDDEN, relatedTarget))
	}

	dispose() {
	$.removeData(this._element, DATA_KEY)
	$(this._element).off(EVENT_KEY)
	this._element = null
	this._menu = null
	if (this._popper !== null) {
	this._popper.destroy()
	this._popper = null
	}
	}

	update() {
	this._inNavbar = this._detectNavbar()
	if (this._popper !== null) {
	this._popper.scheduleUpdate()
	}
	}

	// Private
	_addEventListeners() {
	$(this._element).on(EVENT_CLICK, event => {
	event.preventDefault()
	event.stopPropagation()
	this.toggle()
	})
	}

	_getConfig(config) {
	config = {
	...this.constructor.Default,
	...$(this._element).data(),
	...config
	}

	Util.typeCheckConfig(
	NAME,
	config,
	this.constructor.DefaultType
	)

	return config
	}

	_getMenuElement() {
	if (!this._menu) {
	const parent = Dropdown._getParentFromElement(this._element)

	if (parent) {
	this._menu = parent.querySelector(SELECTOR_MENU)
	}
	}

	return this._menu
	}

	_getPlacement() {
	const $parentDropdown = $(this._element.parentNode)
	let placement = PLACEMENT_BOTTOM

	// Handle dropup
	if ($parentDropdown.hasClass(CLASS_NAME_DROPUP)) {
	placement = $(this._menu).hasClass(CLASS_NAME_MENURIGHT) ?
	PLACEMENT_TOPEND :
	PLACEMENT_TOP
	} else if ($parentDropdown.hasClass(CLASS_NAME_DROPRIGHT)) {
	placement = PLACEMENT_RIGHT
	} else if ($parentDropdown.hasClass(CLASS_NAME_DROPLEFT)) {
	placement = PLACEMENT_LEFT
	} else if ($(this._menu).hasClass(CLASS_NAME_MENURIGHT)) {
	placement = PLACEMENT_BOTTOMEND
	}

	return placement
	}

	_detectNavbar() {
	return $(this._element).closest('.navbar').length > 0
	}

	_getOffset() {
	const offset = {}

	if (typeof this._config.offset === 'function') {
	offset.fn = data => {
	data.offsets = {
	...data.offsets,
	...this._config.offset(data.offsets, this._element)
	}

	return data
	}
	} else {
	offset.offset = this._config.offset
	}

	return offset
	}

	_getPopperConfig() {
	const popperConfig = {
	placement: this._getPlacement(),
	modifiers: {
	offset: this._getOffset(),
	flip: {
	enabled: this._config.flip
	},
	preventOverflow: {
	boundariesElement: this._config.boundary
	}
	}
	}

	// Disable Popper if we have a static display
	if (this._config.display === 'static') {
	popperConfig.modifiers.applyStyle = {
	enabled: false
	}
	}

	return {
	...popperConfig,
	...this._config.popperConfig
	}
	}

	// Static
	static _jQueryInterface(config) {
	return this.each(function () {
	let data = $(this).data(DATA_KEY)
	const _config = typeof config === 'object' ? config : null

	if (!data) {
	data = new Dropdown(this, _config)
	$(this).data(DATA_KEY, data)
	}

	if (typeof config === 'string') {
	if (typeof data[config] === 'undefined') {
	throw new TypeError(`No method named "${config}"`)
	}

	data[config]()
	}
	})
	}

	static _clearMenus(event) {
	if (event && (event.which === RIGHT_MOUSE_BUTTON_WHICH \|\|
	event.type === 'keyup' && event.which !== TAB_KEYCODE)) {
	return
	}

	const toggles = [].slice.call(document.querySelectorAll(SELECTOR_DATA_TOGGLE))

	for (let i = 0, len = toggles.length; i < len; i++) {
	const parent = Dropdown._getParentFromElement(toggles[i])
	const context = $(toggles[i]).data(DATA_KEY)
	const relatedTarget = {
	relatedTarget: toggles[i]
	}

	if (event && event.type === 'click') {
	relatedTarget.clickEvent = event
	}

	if (!context) {
	continue
	}

	const dropdownMenu = context._menu
	if (!$(parent).hasClass(CLASS_NAME_SHOW)) {
	continue
	}

	if (event && (event.type === 'click' &&
	/input\|textarea/i.test(event.target.tagName) \|\| event.type === 'keyup' && event.which === TAB_KEYCODE) &&
	$.contains(parent, event.target)) {
	continue
	}

	const hideEvent = $.Event(EVENT_HIDE, relatedTarget)
	$(parent).trigger(hideEvent)
	if (hideEvent.isDefaultPrevented()) {
	continue
	}

	// If this is a touch-enabled device we remove the extra
	// empty mouseover listeners we added for iOS support
	if ('ontouchstart' in document.documentElement) {
	$(document.body).children().off('mouseover', null, $.noop)
	}

	toggles[i].setAttribute('aria-expanded', 'false')

	if (context._popper) {
	context._popper.destroy()
	}

	$(dropdownMenu).removeClass(CLASS_NAME_SHOW)
	$(parent)
	.removeClass(CLASS_NAME_SHOW)
	.trigger($.Event(EVENT_HIDDEN, relatedTarget))
	}
	}

	static _getParentFromElement(element) {
	let parent
	const selector = Util.getSelectorFromElement(element)

	if (selector) {
	parent = document.querySelector(selector)
	}

	return parent \|\| element.parentNode
	}

	// eslint-disable-next-line complexity
	static _dataApiKeydownHandler(event) {
	// If not input/textarea:
	// - And not a key in REGEXP_KEYDOWN => not a dropdown command
	// If input/textarea:
	// - If space key => not a dropdown command
	// - If key is other than escape
	// - If key is not up or down => not a dropdown command
	// - If trigger inside the menu => not a dropdown command
	if (/input\|textarea/i.test(event.target.tagName) ?
	event.which === SPACE_KEYCODE \|\| event.which !== ESCAPE_KEYCODE &&
	(event.which !== ARROW_DOWN_KEYCODE && event.which !== ARROW_UP_KEYCODE \|\|
	$(event.target).closest(SELECTOR_MENU).length) : !REGEXP_KEYDOWN.test(event.which)) {
	return
	}

	if (this.disabled \|\| $(this).hasClass(CLASS_NAME_DISABLED)) {
	return
	}

	const parent = Dropdown._getParentFromElement(this)
	const isActive = $(parent).hasClass(CLASS_NAME_SHOW)

	if (!isActive && event.which === ESCAPE_KEYCODE) {
	return
	}

	event.preventDefault()
	event.stopPropagation()

	if (!isActive \|\| (event.which === ESCAPE_KEYCODE \|\| event.which === SPACE_KEYCODE)) {
	if (event.which === ESCAPE_KEYCODE) {
	$(parent.querySelector(SELECTOR_DATA_TOGGLE)).trigger('focus')
	}

	$(this).trigger('click')
	return
	}

	const items = [].slice.call(parent.querySelectorAll(SELECTOR_VISIBLE_ITEMS))
	.filter(item => $(item).is(':visible'))

	if (items.length === 0) {
	return
	}

	let index = items.indexOf(event.target)

	if (event.which === ARROW_UP_KEYCODE && index > 0) { // Up
	index--
	}

	if (event.which === ARROW_DOWN_KEYCODE && index < items.length - 1) { // Down
	index++
	}

	if (index < 0) {
	index = 0
	}

	items[index].focus()
	}
	}

	/**
	* Data API implementation
	*/

	$(document)
	.on(EVENT_KEYDOWN_DATA_API, SELECTOR_DATA_TOGGLE, Dropdown._dataApiKeydownHandler)
	.on(EVENT_KEYDOWN_DATA_API, SELECTOR_MENU, Dropdown._dataApiKeydownHandler)
	.on(`${EVENT_CLICK_DATA_API} ${EVENT_KEYUP_DATA_API}`, Dropdown._clearMenus)
	.on(EVENT_CLICK_DATA_API, SELECTOR_DATA_TOGGLE, function (event) {
	event.preventDefault()
	event.stopPropagation()
	Dropdown._jQueryInterface.call($(this), 'toggle')
	})
	.on(EVENT_CLICK_DATA_API, SELECTOR_FORM_CHILD, e => {
	e.stopPropagation()
	})

	/**
	* jQuery
	*/

	$.fn[NAME] = Dropdown._jQueryInterface
	$.fn[NAME].Constructor = Dropdown
	$.fn[NAME].noConflict = () => {
	$.fn[NAME] = JQUERY_NO_CONFLICT
	return Dropdown._jQueryInterface
	}

	export default Dropdown