remove dropdown.js reliance on roles and fix keyboard navigation

js/src/dropdown.js

@@ -25,10 +25,11 @@ const Dropdown = (($) => {
   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}|${SPACE_KEYCODE}`)
+  const REGEXP_KEYDOWN           = new RegExp(`${ARROW_UP_KEYCODE}|${ARROW_DOWN_KEYCODE}|${ESCAPE_KEYCODE}`)
 
   const Event = {
     HIDE             : `hide${EVENT_KEY}`,
@@ -37,8 +38,8 @@ const Dropdown = (($) => {
     SHOWN            : `shown${EVENT_KEY}`,
     CLICK            : `click${EVENT_KEY}`,
     CLICK_DATA_API   : `click${EVENT_KEY}${DATA_API_KEY}`,
-    FOCUSIN_DATA_API : `focusin${EVENT_KEY}${DATA_API_KEY}`,
-    KEYDOWN_DATA_API : `keydown${EVENT_KEY}${DATA_API_KEY}`
+    KEYDOWN_DATA_API : `keydown${EVENT_KEY}${DATA_API_KEY}`,
+    KEYUP_DATA_API   : `keyup${EVENT_KEY}${DATA_API_KEY}`
   }
 
   const ClassName = {
@@ -51,11 +52,9 @@ const Dropdown = (($) => {
     BACKDROP      : '.dropdown-backdrop',
     DATA_TOGGLE   : '[data-toggle="dropdown"]',
     FORM_CHILD    : '.dropdown form',
-    ROLE_MENU     : '[role="menu"]',
-    ROLE_LISTBOX  : '[role="listbox"]',
+    MENU          : '.dropdown-menu',
     NAVBAR_NAV    : '.navbar-nav',
-    VISIBLE_ITEMS : '[role="menu"] li:not(.disabled) a, '
-                  + '[role="listbox"] li:not(.disabled) a'
+    VISIBLE_ITEMS : '.dropdown-menu .dropdown-item:not(.disabled)'
   }
 
 
@@ -164,7 +163,8 @@ const Dropdown = (($) => {
     }
 
     static _clearMenus(event) {
-      if (event && event.which === RIGHT_MOUSE_BUTTON_WHICH) {
+      if (event && (event.which === RIGHT_MOUSE_BUTTON_WHICH ||
+        event.type === 'keyup' && event.which !== TAB_KEYCODE)) {
         return
       }
 
@@ -181,7 +181,7 @@ const Dropdown = (($) => {
         }
 
         if (event && (event.type === 'click' &&
-            /input|textarea/i.test(event.target.tagName) || event.type === 'focusin')
+            /input|textarea/i.test(event.target.tagName) || event.type === 'keyup' && event.which === TAB_KEYCODE)
             && $.contains(parent, event.target)) {
           continue
         }
@@ -218,7 +218,7 @@ const Dropdown = (($) => {
     }
 
     static _dataApiKeydownHandler(event) {
-      if (!REGEXP_KEYDOWN.test(event.which) ||
+      if (!REGEXP_KEYDOWN.test(event.which) || /button/i.test(event.target.tagName) && event.which === SPACE_KEYCODE ||
          /input|textarea/i.test(event.target.tagName)) {
         return
       }
@@ -233,8 +233,8 @@ const Dropdown = (($) => {
       const parent   = Dropdown._getParentFromElement(this)
       const isActive = $(parent).hasClass(ClassName.SHOW)
 
-      if (!isActive && event.which !== ESCAPE_KEYCODE ||
-           isActive && event.which === ESCAPE_KEYCODE) {
+      if (!isActive && (event.which !== ESCAPE_KEYCODE || event.which !== SPACE_KEYCODE) ||
+           isActive && (event.which === ESCAPE_KEYCODE || event.which === SPACE_KEYCODE)) {
 
         if (event.which === ESCAPE_KEYCODE) {
           const toggle = $(parent).find(Selector.DATA_TOGGLE)[0]
@@ -279,9 +279,8 @@ const Dropdown = (($) => {
 
   $(document)
     .on(Event.KEYDOWN_DATA_API, Selector.DATA_TOGGLE,  Dropdown._dataApiKeydownHandler)
-    .on(Event.KEYDOWN_DATA_API, Selector.ROLE_MENU,    Dropdown._dataApiKeydownHandler)
-    .on(Event.KEYDOWN_DATA_API, Selector.ROLE_LISTBOX, Dropdown._dataApiKeydownHandler)
-    .on(`${Event.CLICK_DATA_API} ${Event.FOCUSIN_DATA_API}`, Dropdown._clearMenus)
+    .on(Event.KEYDOWN_DATA_API, Selector.MENU, Dropdown._dataApiKeydownHandler)
+    .on(`${Event.CLICK_DATA_API} ${Event.KEYUP_DATA_API}`, Dropdown._clearMenus)
     .on(Event.CLICK_DATA_API, Selector.DATA_TOGGLE, Dropdown.prototype.toggle)
     .on(Event.CLICK_DATA_API, Selector.FORM_CHILD, (e) => {
       e.stopPropagation()