Merge branch 'v4' of https://github.com/twbs/derpstrap into v4

16 files changed, 394 insertions, 191 deletions

diff --git a/js/.eslintrc b/js/.eslintrc
new file mode 100644
index 000000000..645dac16d
--- /dev/null
+++ b/js/.eslintrc
@@ -0,0 +1,177 @@
+{
+    "parser": "babel-eslint",
+    "env": {
+        "browser": true
+    },
+    "rules": {
+
+        // Possible Errors
+        "comma-dangle": [2, "never"],
+        "no-cond-assign": 2,
+        "no-console": 2,
+        "no-constant-condition": 2,
+        "no-control-regex": 2,
+        "no-debugger": 2,
+        "no-dupe-args": 2,
+        "no-dupe-keys": 2,
+        "no-duplicate-case": 2,
+        "no-empty-character-class": 2,
+        "no-empty": 2,
+        "no-ex-assign": 2,
+        "no-extra-boolean-cast": 2,
+        "no-extra-parens": 0,
+        "no-extra-semi": 2,
+        "no-func-assign": 2,
+        "no-inner-declarations": 2,
+        "no-invalid-regexp": 2,
+        "no-irregular-whitespace": 0,
+        "no-negated-in-lhs": 2,
+        "no-obj-calls": 2,
+        "no-regex-spaces": 2,
+        "no-sparse-arrays": 2,
+        "no-unreachable": 2,
+        "use-isnan": 2,
+        "valid-jsdoc": 0,
+        "valid-typeof": 2,
+        "no-unexpected-multiline": 2,
+
+        //Best Practices
+        "accessor-pairs": 2,
+        "block-scoped-var": 2,
+        "consistent-return": 2,
+        "curly": 2,
+        "default-case": 2,
+        "dot-notation": 0,
+        "dot-location": 0,
+        "eqeqeq": 2,
+        "guard-for-in": 2,
+        "no-alert": 2,
+        "no-caller": 2,
+        "no-div-regex": 2,
+        "no-else-return": 2,
+        "no-empty-label": 2,
+        "no-eq-null": 2,
+        "no-eval": 2,
+        "no-extend-native": 2,
+        "no-extra-bind": 2,
+        "no-fallthrough": 2,
+        "no-floating-decimal": 2,
+        "no-implicit-coercion": 2,
+        "no-implied-eval": 2,
+        "no-invalid-this": 0,
+        "no-iterator": 2,
+        "no-labels": 2,
+        "no-lone-blocks": 2,
+        "no-loop-func": 2,
+        "no-multi-spaces": 0,
+        "no-multi-str": 0,
+        "no-native-reassign": 2,
+        "no-new-func": 0,
+        "no-new-wrappers": 2,
+        "no-new": 2,
+        "no-octal-escape": 2,
+        "no-octal": 2,
+        "no-param-reassign": 0,
+        "no-process-env": 2,
+        "no-proto": 2,
+        "no-redeclare": 2,
+        "no-return-assign": 2,
+        "no-script-url": 2,
+        "no-self-compare": 2,
+        "no-sequences": 2,
+        "no-throw-literal": 2,
+        "no-unused-expressions": 2,
+        "no-useless-call": 2,
+        "no-void": 2,
+        "no-warning-comments": 0,
+        "no-with": 2,
+        "radix": 2,
+        "vars-on-top": 0,
+        "wrap-iife": 2,
+        "yoda": 2,
+
+        // Variables
+        "init-declarations": 0,
+        "no-catch-shadow": 2,
+        "no-delete-var": 2,
+        "no-label-var": 2,
+        "no-shadow-restricted-names": 2,
+        "no-shadow": 0,
+        "no-undef-init": 2,
+        "no-undef": 0,
+        "no-undefined": 0,
+        "no-unused-vars": 2,
+        "no-use-before-define": 0,
+
+        // Stylistic
+        "array-bracket-spacing": 2,
+        "block-spacing": 2,
+        "brace-style": 2,
+        "camelcase": 2,
+        "comma-spacing": 2,
+        "comma-style": 2,
+        "computed-property-spacing": 2,
+        "consistent-this": 2,
+        "eol-last": 2,
+        "func-names": 0,
+        "func-style": 0,
+        "indent": 0,
+        "key-spacing": 0,
+        "lines-around-comment": 0,
+        "linebreak-style": 2,
+        "new-cap": 0,
+        "new-parens": 2,
+        "newline-after-var": 0,
+        "no-array-constructor": 2,
+        "no-continue": 0,
+        "no-inline-comments": 0,
+        "no-lonely-if": 2,
+        "no-mixed-spaces-and-tabs": 2,
+        "no-multiple-empty-lines": 2,
+        "no-nested-ternary": 0,
+        "no-new-object": 2,
+        "no-spaced-func": 2,
+        "no-ternary": 0,
+        "no-trailing-spaces": 2,
+        "no-underscore-dangle": 0,
+        "no-unneeded-ternary": 2,
+        "object-curly-spacing": [1, "always"],
+        "one-var": 0,
+        "operator-assignment": 2,
+        "operator-linebreak": 0,
+        "padded-blocks": 0,
+        "quote-props": 0,
+        "quotes": 0,
+        "semi-spacing": 0,
+        "semi": [2, "never"],
+        "sort-vars": 2,
+        "space-after-keywords": 2,
+        "space-before-blocks": 2,
+        "space-before-function-paren": 0,
+        "space-in-parens": 2,
+        "space-infix-ops": 2,
+        "space-return-throw-case": 2,
+        "space-unary-ops": 2,
+        "spaced-comment": 2,
+        "spaced-comment": 2,
+
+        // es6
+        "arrow-parens": 2,
+        "arrow-spacing": 2,
+        "constructor-super": 2,
+        "generator-star-spacing": 2,
+        "no-class-assign": 2,
+        "no-const-assign": 2,
+        "no-dupe-class-members": 2,
+        "no-this-before-super": 2,
+        "no-var": 2,
+        "object-shorthand": 2,
+        "prefer-arrow-callback": 2,
+        "prefer-const": 0,
+        "prefer-spread": 2,
+        "prefer-reflect": 0,
+        "prefer-template": 2,
+        "require-yield": 2
+
+    }
+}
diff --git a/js/dist/util.js b/js/dist/util.js
index 56296252b..a2ae5f299 100644
--- a/js/dist/util.js
+++ b/js/dist/util.js
@@ -1,3 +1,4 @@
+
 /**
  * --------------------------------------------------------------------------
  * Bootstrap (v4.0.0): util.js
@@ -100,7 +101,7 @@ var Util = (function ($) {
     TRANSITION_END: 'bsTransitionEnd',
 
     getUID: function getUID(prefix) {
-      do prefix += ~ ~(Math.random() * 1000000); while (document.getElementById(prefix));
+      do { prefix += ~ ~(Math.random() * 1000000); } while (document.getElementById(prefix));
       return prefix;
     },
 
diff --git a/js/src/alert.js b/js/src/alert.js
index e58a31175..da4e5b6a5 100644
--- a/js/src/alert.js
+++ b/js/src/alert.js
@@ -86,8 +86,8 @@ const Alert = (($) => {
     // private
 
     _getRootElement(element) {
-      let parent   = false
       let selector = Util.getSelectorFromElement(element)
+      let parent   = false
 
       if (selector) {
         parent = $(selector)[0]
@@ -101,7 +101,8 @@ const Alert = (($) => {
     }
 
     _triggerCloseEvent(element) {
-      var closeEvent = $.Event(Event.CLOSE)
+      let closeEvent = $.Event(Event.CLOSE)
+
       $(element).trigger(closeEvent)
       return closeEvent
     }
diff --git a/js/src/button.js b/js/src/button.js
index 8210e8ae0..58ef66b8b 100644
--- a/js/src/button.js
+++ b/js/src/button.js
@@ -20,7 +20,6 @@ const Button = (($) => {
   const EVENT_KEY           = `.${DATA_KEY}`
   const DATA_API_KEY        = '.data-api'
   const JQUERY_NO_CONFLICT  = $.fn[NAME]
-  const TRANSITION_DURATION = 150
 
   const ClassName = {
     ACTIVE : 'active',
@@ -67,7 +66,7 @@ const Button = (($) => {
 
     toggle() {
       let triggerChangeEvent = true
-      let rootElement = $(this._element).closest(
+      let rootElement        = $(this._element).closest(
         Selector.DATA_TOGGLE
       )[0]
 
@@ -137,7 +136,7 @@ const Button = (($) => {
    */
 
   $(document)
-    .on(Event.CLICK_DATA_API, Selector.DATA_TOGGLE_CARROT, function (event) {
+    .on(Event.CLICK_DATA_API, Selector.DATA_TOGGLE_CARROT, (event) => {
       event.preventDefault()
 
       let button = event.target
@@ -148,8 +147,8 @@ const Button = (($) => {
 
       Button._jQueryInterface.call($(button), 'toggle')
     })
-    .on(Event.FOCUS_BLUR_DATA_API, Selector.DATA_TOGGLE_CARROT, function (event) {
-      var button = $(event.target).closest(Selector.BUTTON)[0]
+    .on(Event.FOCUS_BLUR_DATA_API, Selector.DATA_TOGGLE_CARROT, (event) => {
+      let button = $(event.target).closest(Selector.BUTTON)[0]
       $(button).toggleClass(ClassName.FOCUS, /^focus(in)?$/.test(event.type))
     })
 
diff --git a/js/src/carousel.js b/js/src/carousel.js
index c11f0a599..efacd9494 100644
--- a/js/src/carousel.js
+++ b/js/src/carousel.js
@@ -171,13 +171,13 @@ const Carousel = (($) => {
         return
       }
 
-      if (activeIndex == index) {
+      if (activeIndex === index) {
         this.pause()
         this.cycle()
         return
       }
 
-      var direction = index > activeIndex ?
+      let direction = index > activeIndex ?
         Direction.NEXT :
         Direction.PREVIOUS
 
@@ -213,7 +213,7 @@ const Carousel = (($) => {
           .on(Event.KEYDOWN, $.proxy(this._keydown, this))
       }
 
-      if (this._config.pause == 'hover' &&
+      if (this._config.pause === 'hover' &&
         !('ontouchstart' in document.documentElement)) {
         $(this._element)
           .on(Event.MOUSEENTER, $.proxy(this.pause, this))
@@ -224,7 +224,9 @@ const Carousel = (($) => {
     _keydown(event) {
       event.preventDefault()
 
-      if (/input|textarea/i.test(event.target.tagName)) return
+      if (/input|textarea/i.test(event.target.tagName)) {
+        return
+      }
 
       switch (event.which) {
         case 37: this.prev(); break
@@ -244,13 +246,13 @@ const Carousel = (($) => {
       let activeIndex     = this._getItemIndex(activeElement)
       let lastItemIndex   = (this._items.length - 1)
       let isGoingToWrap   = (isPrevDirection && activeIndex === 0) ||
-                            (isNextDirection && activeIndex == lastItemIndex)
+                            (isNextDirection && activeIndex === lastItemIndex)
 
       if (isGoingToWrap && !this._config.wrap) {
         return activeElement
       }
 
-      let delta     = direction == Direction.PREVIOUS ? -1 : 1
+      let delta     = direction === Direction.PREVIOUS ? -1 : 1
       let itemIndex = (activeIndex + delta) % this._items.length
 
       return itemIndex === -1 ?
@@ -260,7 +262,7 @@ const Carousel = (($) => {
 
     _triggerSlideEvent(relatedTarget, directionalClassname) {
       let slideEvent = $.Event(Event.SLIDE, {
-        relatedTarget: relatedTarget,
+        relatedTarget,
         direction: directionalClassname
       })
 
@@ -290,9 +292,9 @@ const Carousel = (($) => {
       let nextElement   = element || activeElement &&
         this._getItemByDirection(direction, activeElement)
 
-      let isCycling = !!this._interval
+      let isCycling = Boolean(this._interval)
 
-      let directionalClassName = direction == Direction.NEXT ?
+      let directionalClassName = direction === Direction.NEXT ?
         ClassName.LEFT :
         ClassName.RIGHT
 
@@ -319,7 +321,7 @@ const Carousel = (($) => {
 
       this._setActiveIndicatorElement(nextElement)
 
-      var slidEvent = $.Event(Event.SLID, {
+      let slidEvent = $.Event(Event.SLID, {
         relatedTarget: nextElement,
         direction: directionalClassName
       })
@@ -372,7 +374,7 @@ const Carousel = (($) => {
 
     static _jQueryInterface(config) {
       return this.each(function () {
-        let data    = $(this).data(DATA_KEY)
+        let data      = $(this).data(DATA_KEY)
         let _config = $.extend({}, Default, $(this).data())
 
         if (typeof config === 'object') {
@@ -386,7 +388,7 @@ const Carousel = (($) => {
           $(this).data(DATA_KEY, data)
         }
 
-        if (typeof config == 'number') {
+        if (typeof config === 'number') {
           data.to(config)
 
         } else if (action) {
@@ -412,9 +414,9 @@ const Carousel = (($) => {
         return
       }
 
-      let config = $.extend({}, $(target).data(), $(this).data())
-
+      let config     = $.extend({}, $(target).data(), $(this).data())
       let slideIndex = this.getAttribute('data-slide-to')
+
       if (slideIndex) {
         config.interval = false
       }
@@ -440,7 +442,7 @@ const Carousel = (($) => {
   $(document)
     .on(Event.CLICK_DATA_API, Selector.DATA_SLIDE, Carousel._dataApiClickHandler)
 
-  $(window).on(Event.LOAD_DATA_API, function () {
+  $(window).on(Event.LOAD_DATA_API, () => {
     $(Selector.DATA_RIDE).each(function () {
       let $carousel = $(this)
       Carousel._jQueryInterface.call($carousel, $carousel.data())
diff --git a/js/src/collapse.js b/js/src/collapse.js
index e911c98d1..e46d3ec60 100644
--- a/js/src/collapse.js
+++ b/js/src/collapse.js
@@ -182,15 +182,14 @@ const Collapse = (($) => {
         return
       }
 
-      let scrollSize = 'scroll'
-        + (dimension[0].toUpperCase()
-        + dimension.slice(1))
+      let capitalizedDimension = dimension[0].toUpperCase() + dimension.slice(1)
+      let scrollSize           = `scroll${capitalizedDimension}`
 
       $(this._element)
         .one(Util.TRANSITION_END, complete)
         .emulateTransitionEnd(TRANSITION_DURATION)
 
-      this._element.style[dimension] = this._element[scrollSize] + 'px'
+      this._element.style[dimension] = `${this._element[scrollSize]}px`
     }
 
     hide() {
@@ -205,11 +204,11 @@ const Collapse = (($) => {
         return
       }
 
-      let dimension = this._getDimension()
+      let dimension       = this._getDimension()
       let offsetDimension = dimension === Dimension.WIDTH ?
         'offsetWidth' : 'offsetHeight'
 
-      this._element.style[dimension] = this._element[offsetDimension] + 'px'
+      this._element.style[dimension] = `${this._element[offsetDimension]}px`
 
       Util.reflow(this._element)
 
@@ -239,7 +238,8 @@ const Collapse = (($) => {
       this._element.style[dimension] = 0
 
       if (!Util.supportsTransitionEnd()) {
-        return complete()
+        complete()
+        return
       }
 
       $(this._element)
@@ -266,7 +266,7 @@ const Collapse = (($) => {
 
     _getConfig(config) {
       config = $.extend({}, Default, config)
-      config.toggle = !!config.toggle // coerce string values
+      config.toggle = Boolean(config.toggle) // coerce string values
       Util.typeCheckConfig(NAME, config, DefaultType)
       return config
     }
@@ -351,8 +351,7 @@ const Collapse = (($) => {
     event.preventDefault()
 
     let target = Collapse._getTargetFromElement(this)
-
-    let data = $(target).data(DATA_KEY)
+    let data   = $(target).data(DATA_KEY)
     let config = data ? 'toggle' : $(this).data()
 
     Collapse._jQueryInterface.call($(target), config)
diff --git a/js/src/dropdown.js b/js/src/dropdown.js
index 1c4866dc2..734e64312 100644
--- a/js/src/dropdown.js
+++ b/js/src/dropdown.js
@@ -78,7 +78,7 @@ const Dropdown = (($) => {
 
     toggle() {
       if (this.disabled || $(this).hasClass(ClassName.DISABLED)) {
-        return
+        return false
       }
 
       let parent   = Dropdown._getParentFromElement(this)
@@ -106,7 +106,7 @@ const Dropdown = (($) => {
       $(parent).trigger(showEvent)
 
       if (showEvent.isDefaultPrevented()) {
-        return
+        return false
       }
 
       this.focus()
@@ -239,9 +239,17 @@ const Dropdown = (($) => {
 
       let index = items.indexOf(event.target)
 
-      if (event.which === 38 && index > 0)                index--  // up
-      if (event.which === 40 && index < items.length - 1) index++  // down
-      if (!~index)                                        index = 0
+      if (event.which === 38 && index > 0) { // up
+        index--
+      }
+
+      if (event.which === 40 && index < items.length - 1) { // down
+        index++
+      }
+
+      if (!~index) {
+        index = 0
+      }
 
       items[index].focus()
     }
@@ -261,9 +269,9 @@ const Dropdown = (($) => {
     .on(Event.KEYDOWN_DATA_API, Selector.ROLE_LISTBOX, Dropdown._dataApiKeydownHandler)
     .on(Event.CLICK_DATA_API, Dropdown._clearMenus)
     .on(Event.CLICK_DATA_API, Selector.DATA_TOGGLE, Dropdown.prototype.toggle)
-    .on(Event.CLICK_DATA_API, Selector.FORM_CHILD,  function (e) {
-       e.stopPropagation()
-     })
+    .on(Event.CLICK_DATA_API, Selector.FORM_CHILD, (e) => {
+      e.stopPropagation()
+    })
 
 
   /**
diff --git a/js/src/modal.js b/js/src/modal.js
index df49c1a4c..128863273 100644
--- a/js/src/modal.js
+++ b/js/src/modal.js
@@ -110,7 +110,7 @@ const Modal = (($) => {
 
     show(relatedTarget) {
       let showEvent = $.Event(Event.SHOW, {
-        relatedTarget: relatedTarget
+        relatedTarget
       })
 
       $(this._element).trigger(showEvent)
@@ -231,14 +231,18 @@ const Modal = (($) => {
 
       $(this._element).addClass(ClassName.IN)
 
-      if (this._config.focus) this._enforceFocus()
+      if (this._config.focus) {
+        this._enforceFocus()
+      }
 
       let shownEvent = $.Event(Event.SHOWN, {
-        relatedTarget: relatedTarget
+        relatedTarget
       })
 
       let transitionComplete = () => {
-        if (this._config.focus) this._element.focus()
+        if (this._config.focus) {
+          this._element.focus()
+        }
         $(this._element).trigger(shownEvent)
       }
 
@@ -389,11 +393,11 @@ const Modal = (($) => {
         this._element.scrollHeight > document.documentElement.clientHeight
 
       if (!this._isBodyOverflowing && isModalOverflowing) {
-        this._element.style.paddingLeft = this._scrollbarWidth + 'px'
+        this._element.style.paddingLeft = `${this._scrollbarWidth}px`
       }
 
       if (this._isBodyOverflowing && !isModalOverflowing) {
-        this._element.style.paddingRight = this._scrollbarWidth + 'px'
+        this._element.style.paddingRight = `${this._scrollbarWidth}px~`
       }
     }
 
@@ -423,7 +427,7 @@ const Modal = (($) => {
 
       if (this._isBodyOverflowing) {
         document.body.style.paddingRight =
-          bodyPadding + this._scrollbarWidth + 'px'
+          bodyPadding + `${this._scrollbarWidth}px`
       }
     }
 
diff --git a/js/src/popover.js b/js/src/popover.js
index 31c7a3ae1..30c0e4acb 100644
--- a/js/src/popover.js
+++ b/js/src/popover.js
@@ -141,7 +141,7 @@ const Popover = (($) => {
 
     _getContent() {
       return this.element.getAttribute('data-content')
-        || (typeof this.config.content == 'function' ?
+        || (typeof this.config.content === 'function' ?
               this.config.content.call(this.element) :
               this.config.content)
     }
diff --git a/js/src/scrollspy.js b/js/src/scrollspy.js
index a407511f6..df33f48de 100644
--- a/js/src/scrollspy.js
+++ b/js/src/scrollspy.js
@@ -293,7 +293,7 @@ const ScrollSpy = (($) => {
    * ------------------------------------------------------------------------
    */
 
-  $(window).on(Event.LOAD_DATA_API, function () {
+  $(window).on(Event.LOAD_DATA_API, () => {
     let scrollSpys = $.makeArray($(Selector.DATA_SPY))
 
     for (let i = scrollSpys.length; i--;) {
diff --git a/js/src/tab.js b/js/src/tab.js
index 4d8d7dec8..9d793417a 100644
--- a/js/src/tab.js
+++ b/js/src/tab.js
@@ -77,7 +77,7 @@ const Tab = (($) => {
 
     show() {
       if (this._element.parentNode &&
-         (this._element.parentNode.nodeType == Node.ELEMENT_NODE) &&
+         (this._element.parentNode.nodeType === Node.ELEMENT_NODE) &&
          ($(this._element).parent().hasClass(ClassName.ACTIVE))) {
         return
       }
@@ -157,7 +157,7 @@ const Tab = (($) => {
       let isTransitioning = callback
         && Util.supportsTransitionEnd()
         && ((active && $(active).hasClass(ClassName.FADE))
-           || !!$(container).find(Selector.FADE_CHILD)[0])
+           || Boolean($(container).find(Selector.FADE_CHILD)[0]))
 
       let complete = $.proxy(
         this._transitionComplete,
diff --git a/js/src/tooltip.js b/js/src/tooltip.js
index 5d62e154a..a65caf26e 100644
--- a/js/src/tooltip.js
+++ b/js/src/tooltip.js
@@ -174,11 +174,9 @@ const Tooltip = (($) => {
     }
 
     toggle(event) {
-      let context = this
-      let dataKey = this.constructor.DATA_KEY
-
       if (event) {
-        context = $(event.currentTarget).data(dataKey)
+        let dataKey = this.constructor.DATA_KEY
+        let context = $(event.currentTarget).data(dataKey)
 
         if (!context) {
           context = new this.constructor(
@@ -197,9 +195,13 @@ const Tooltip = (($) => {
         }
 
       } else {
-        $(context.getTipElement()).hasClass(ClassName.IN) ?
-          context._leave(null, context) :
-          context._enter(null, context)
+
+        if ($(this.getTipElement()).hasClass(ClassName.IN)) {
+          this._leave(null, this)
+          return
+        }
+
+        this._enter(null, this)
       }
     }
 
@@ -267,9 +269,9 @@ const Tooltip = (($) => {
         $(this.element).trigger(this.constructor.Event.INSERTED)
 
         this._tether = new Tether({
+          attachment,
           element     : tip,
           target      : this.element,
-          attachment  : attachment,
           classes     : TetherClass,
           classPrefix : CLASS_PREFIX,
           offset      : this.config.offset,
@@ -292,11 +294,14 @@ const Tooltip = (($) => {
           }
         }
 
-        Util.supportsTransitionEnd() && $(this.tip).hasClass(ClassName.FADE) ?
+        if (Util.supportsTransitionEnd() && $(this.tip).hasClass(ClassName.FADE)) {
           $(this.tip)
             .one(Util.TRANSITION_END, complete)
-            .emulateTransitionEnd(Tooltip._TRANSITION_DURATION) :
-          complete()
+            .emulateTransitionEnd(Tooltip._TRANSITION_DURATION)
+          return
+        }
+
+        complete()
       }
     }
 
@@ -343,7 +348,7 @@ const Tooltip = (($) => {
     // protected
 
     isWithContent() {
-      return !!this.getTitle()
+      return Boolean(this.getTitle())
     }
 
     getTipElement() {
@@ -407,10 +412,10 @@ const Tooltip = (($) => {
           )
 
         } else if (trigger !== Trigger.MANUAL) {
-          let eventIn  = trigger == Trigger.HOVER ?
+          let eventIn  = trigger === Trigger.HOVER ?
             this.constructor.Event.MOUSEENTER :
             this.constructor.Event.FOCUSIN
-          let eventOut = trigger == Trigger.HOVER ?
+          let eventOut = trigger === Trigger.HOVER ?
             this.constructor.Event.MOUSELEAVE :
             this.constructor.Event.FOCUSOUT
 
@@ -471,7 +476,7 @@ const Tooltip = (($) => {
 
       if (event) {
         context._activeTrigger[
-          event.type == 'focusin' ? Trigger.FOCUS : Trigger.HOVER
+          event.type === 'focusin' ? Trigger.FOCUS : Trigger.HOVER
         ] = true
       }
 
@@ -512,7 +517,7 @@ const Tooltip = (($) => {
 
       if (event) {
         context._activeTrigger[
-          event.type == 'focusout' ? Trigger.FOCUS : Trigger.HOVER
+          event.type === 'focusout' ? Trigger.FOCUS : Trigger.HOVER
         ] = false
       }
 
@@ -575,9 +580,8 @@ const Tooltip = (($) => {
 
       if (this.config) {
         for (let key in this.config) {
-          let value = this.config[key]
-          if (this.constructor.Default[key] !== value) {
-            config[key] = value
+          if (this.constructor.Default[key] !== this.config[key]) {
+            config[key] = this.config[key]
           }
         }
       }
diff --git a/js/src/util.js b/js/src/util.js
index 86bea6578..f4a584125 100644
--- a/js/src/util.js
+++ b/js/src/util.js
@@ -29,14 +29,14 @@ const Util = (($) => {
   }
 
   function isElement(obj) {
-    return (obj[0] || obj).nodeType;
+    return (obj[0] || obj).nodeType
   }
 
   function getSpecialTransitionEndEvent() {
     return {
       bindType: transition.end,
       delegateType: transition.end,
-      handle: function (event) {
+      handle(event) {
         if ($(event.target).is(this)) {
           return event.handleObj.handler.apply(this, arguments)
         }
@@ -51,7 +51,7 @@ const Util = (($) => {
 
     let el = document.createElement('bootstrap')
 
-    for (var name in TransitionEndEvent) {
+    for (let name in TransitionEndEvent) {
       if (el.style[name] !== undefined) {
         return { end: TransitionEndEvent[name] }
       }
@@ -63,7 +63,7 @@ const Util = (($) => {
   function transitionEndEmulator(duration) {
     let called = false
 
-    $(this).one(Util.TRANSITION_END, function () {
+    $(this).one(Util.TRANSITION_END, () => {
       called = true
     })
 
@@ -98,8 +98,9 @@ const Util = (($) => {
     TRANSITION_END: 'bsTransitionEnd',
 
     getUID(prefix) {
-      do prefix += ~~(Math.random() * 1000000)
-      while (document.getElementById(prefix))
+      do {
+        prefix += ~~(Math.random() * 1000000)
+      } while (document.getElementById(prefix))
       return prefix
     },
 
@@ -123,28 +124,31 @@ const Util = (($) => {
     },
 
     supportsTransitionEnd() {
-      return !!transition
+      return Boolean(transition)
     },
 
     typeCheckConfig(componentName, config, configTypes) {
-
       for (let property in configTypes) {
-        let expectedTypes = configTypes[property]
-        let value         = config[property]
-        let valueType
-
-        if (value && isElement(value)) valueType = 'element'
-        else valueType = toType(value)
-
-        if (!new RegExp(expectedTypes).test(valueType)) {
-          throw new Error(
-            `${componentName.toUpperCase()}: ` +
-            `Option "${property}" provided type "${valueType}" ` +
-            `but expected type "${expectedTypes}".`)
+        if (configTypes.hasOwnProperty(property)) {
+          let expectedTypes = configTypes[property]
+          let value         = config[property]
+          let valueType
+
+          if (value && isElement(value)) {
+            valueType = 'element'
+          } else {
+            valueType = toType(value)
+          }
+
+          if (!new RegExp(expectedTypes).test(valueType)) {
+            throw new Error(
+              `${componentName.toUpperCase()}: ` +
+              `Option "${property}" provided type "${valueType}" ` +
+              `but expected type "${expectedTypes}".`)
+          }
         }
       }
     }
-
   }
 
   setTransitionEndSupport()
diff --git a/js/tests/unit/phantom.js b/js/tests/unit/phantom.js
index 2791bd841..525aea002 100644
--- a/js/tests/unit/phantom.js
+++ b/js/tests/unit/phantom.js
@@ -76,29 +76,26 @@
 // shoutout mdn: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Function/bind#Polyfill
 
 if (!Function.prototype.bind) {
-  Function.prototype.bind = function(oThis) {
+  Function.prototype.bind = function (oThis) {
     if (typeof this !== 'function') {
       // closest thing possible to the ECMAScript 5
       // internal IsCallable function
       throw new TypeError('Function.prototype.bind - what is trying to be bound is not callable');
     }
 
-    var aArgs   = Array.prototype.slice.call(arguments, 1),
-        fToBind = this,
-        fNOP    = function() {},
-        fBound  = function() {
-          return fToBind.apply(this instanceof fNOP
-                 ? this
-                 : oThis,
-                 aArgs.concat(Array.prototype.slice.call(arguments)));
-        };
+    var aArgs   = Array.prototype.slice.call(arguments, 1)
+    var fToBind = this
+    var FNOP    = function () {}
+    var fBound  = function () {
+      return fToBind.apply(this instanceof FNOP ? this : oThis, aArgs.concat(Array.prototype.slice.call(arguments)))
+    }
 
     if (this.prototype) {
       // native functions don't have a prototype
-      fNOP.prototype = this.prototype;
+      FNOP.prototype = this.prototype
     }
-    fBound.prototype = new fNOP();
+    fBound.prototype = new FNOP()
 
-    return fBound;
-  };
+    return fBound
+  }
 }
diff --git a/js/tests/visual/dropdown.html b/js/tests/visual/dropdown.html
index f9df5d07e..5ade9dd18 100644
--- a/js/tests/visual/dropdown.html
+++ b/js/tests/visual/dropdown.html
@@ -22,68 +22,72 @@
     <h1>Dropdown <small>Bootstrap Visual Test</small></h1>
   </div>
 
-  <nav id="navbar-example" class="navbar navbar-default navbar-static-top" role="navigation">
-    <div class="container-fluid">
-      <button class="navbar-toggler hidden-sm-up" type="button" data-toggle="collapse" data-target="#exCollapsingNavbar2">
-        &#9776;
-      </button>
-      <div class="collapse navbar-toggleable-xs" id="exCollapsingNavbar2">
-        <ul class="nav navbar-nav pull-left">
-          <li class="dropdown nav-item">
-            <a id="drop1" href="#" role="button" class="dropdown-toggle nav-link" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false">
-              Dropdown
-            </a>
-            <ul class="dropdown-menu" aria-labelledby="drop1">
-              <li><a href="https://twitter.com/fat">Action</a></li>
-              <li><a href="https://twitter.com/fat">Another action</a></li>
-              <li><a href="https://twitter.com/fat">Something else here</a></li>
-              <li role="separator" class="divider"></li>
-              <li><a href="https://twitter.com/fat">Separated link</a></li>
-            </ul>
-          </li>
-          <li class="dropdown nav-item">
-            <a href="#" id="drop2" role="button" class="dropdown-toggle nav-link" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false">
-              Dropdown 2
-            </a>
-            <ul class="dropdown-menu" aria-labelledby="drop2">
-              <li><a href="https://twitter.com/fat">Action</a></li>
-              <li><a href="https://twitter.com/fat">Another action</a></li>
-              <li><a href="https://twitter.com/fat">Something else here</a></li>
-              <li role="separator" class="divider"></li>
-              <li><a href="https://twitter.com/fat">Separated link</a></li>
-            </ul>
-          </li>
-        </ul>
-        <ul class="nav navbar-nav pull-right">
-          <li id="fat-menu" class="dropdown nav-item">
-            <a href="#" id="drop3" role="button" class="dropdown-toggle nav-link" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false">
-              Dropdown 3
-            </a>
-            <ul class="dropdown-menu" aria-labelledby="drop3">
-              <li><a href="https://twitter.com/fat">Action</a></li>
-              <li><a href="https://twitter.com/fat">Another action</a></li>
-              <li><a href="https://twitter.com/fat">Something else here</a></li>
-              <li role="separator" class="divider"></li>
-              <li><a href="https://twitter.com/fat">Separated link</a></li>
-            </ul>
-          </li>
-        </ul>
-      </div>
+  <nav id="navbar-example" class="navbar navbar-light bg-faded" role="navigation">
+    <button class="navbar-toggler hidden-sm-up" type="button" data-toggle="collapse" data-target="#exCollapsingNavbar2">
+      &#9776;
+    </button>
+
+    <div class="collapse navbar-toggleable-xs" id="exCollapsingNavbar2">
+
+      <ul class="nav navbar-nav pull-left">
+
+        <li class="dropdown nav-item">
+          <a id="drop1" href="#" role="button" class="dropdown-toggle nav-link" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false">
+            Dropdown
+          </a>
+          <div class="dropdown-menu" aria-labelledby="drop1">
+            <a class="dropdown-item" href="https://twitter.com/fat">Action</a>
+            <a class="dropdown-item" href="https://twitter.com/fat">Another action</a>
+            <a class="dropdown-item" href="https://twitter.com/fat">Something else here</a>
+            <div class="dropdown-divider"></div>
+            <a class="dropdown-item" href="https://twitter.com/fat">Separated link</a>
+          </div>
+        </li>
+
+        <li class="dropdown nav-item">
+          <a href="#" id="drop2" role="button" class="dropdown-toggle nav-link" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false">
+            Dropdown 2
+          </a>
+          <div class="dropdown-menu" aria-labelledby="drop2">
+            <a class="dropdown-item" href="https://twitter.com/fat">Action</a>
+            <a class="dropdown-item" href="https://twitter.com/fat">Another action</a>
+            <a class="dropdown-item" href="https://twitter.com/fat">Something else here</a>
+            <div class="dropdown-divider"></div>
+            <a class="dropdown-item" href="https://twitter.com/fat">Separated link</a>
+          </div>
+        </li>
+
+      </ul>
+
+      <ul class="nav navbar-nav pull-right">
+        <li id="fat-menu" class="dropdown nav-item">
+          <a href="#" id="drop3" role="button" class="dropdown-toggle nav-link" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false">
+            Dropdown 3
+          </a>
+          <div class="dropdown-menu" aria-labelledby="drop3">
+            <a class="dropdown-item" href="https://twitter.com/fat">Action</a>
+            <a class="dropdown-item" href="https://twitter.com/fat">Another action</a>
+            <a class="dropdown-item" href="https://twitter.com/fat">Something else here</a>
+            <div class="dropdown-divider"></div>
+            <a class="dropdown-item" href="https://twitter.com/fat">Separated link</a>
+          </div>
+        </li>
+      </ul>
     </div>
   </nav>
 
-  <ul class="nav nav-pills">
+  <ul class="nav nav-pills m-t-lg">
     <li class="active nav-item"><a href="#" class="nav-link">Regular link</a></li>
     <li class="dropdown nav-item">
       <a id="drop4" class="nav-link" role="button" data-toggle="dropdown" href="#" aria-haspopup="true" aria-expanded="false">
         Dropdown
       </a>
       <ul id="menu1" class="dropdown-menu" aria-labelledby="drop4">
-        <li><a href="https://twitter.com/fat">Action</a></li>
-        <li><a href="https://twitter.com/fat">Another action</a></li>
-        <li><a href="https://twitter.com/fat">Something else here</a></li>
-        <li role="separator" class="divider"></li>
-        <li><a href="https://twitter.com/fat">Separated link</a></li>
+        <a class="dropdown-item" href="https://twitter.com/fat">Action</a>
+        <a class="dropdown-item" href="https://twitter.com/fat">Another action</a>
+        <a class="dropdown-item" href="https://twitter.com/fat">Something else here</a>
+        <div class="dropdown-divider"></div>
+        <a class="dropdown-item" href="https://twitter.com/fat">Separated link</a>
       </ul>
     </li>
     <li class="dropdown nav-item">
@@ -91,11 +95,11 @@
         Dropdown 2
       </a>
       <ul id="menu2" class="dropdown-menu" aria-labelledby="drop5">
-        <li><a href="https://twitter.com/fat">Action</a></li>
-        <li><a href="https://twitter.com/fat">Another action</a></li>
-        <li><a href="https://twitter.com/fat">Something else here</a></li>
-        <li role="separator" class="divider"></li>
-        <li><a href="https://twitter.com/fat">Separated link</a></li>
+        <a class="dropdown-item" href="https://twitter.com/fat">Action</a>
+        <a class="dropdown-item" href="https://twitter.com/fat">Another action</a>
+        <a class="dropdown-item" href="https://twitter.com/fat">Something else here</a>
+        <div class="dropdown-divider"></div>
+        <a class="dropdown-item" href="https://twitter.com/fat">Separated link</a>
       </ul>
     </li>
   </ul>
diff --git a/js/tests/visual/modal.html b/js/tests/visual/modal.html
index 7bb38ebf0..047916707 100644
--- a/js/tests/visual/modal.html
+++ b/js/tests/visual/modal.html
@@ -25,30 +25,30 @@
 </head>
 <body>
 
-<nav class="navbar navbar-default navbar-static-top">
-  <div class="container-fluid">
-    <div class="navbar-header">
-      <button type="button" class="navbar-toggle collapsed" data-toggle="collapse" data-target="#navbar" aria-expanded="false" aria-controls="navbar">
-        <span class="sr-only">Toggle navigation</span>
-        <span class="icon-bar"></span>
-        <span class="icon-bar"></span>
-        <span class="icon-bar"></span>
-      </button>
-      <a class="navbar-brand" href="#">navbar-static-top</a>
-    </div>
-    <div id="navbar" class="navbar-collapse collapse">
-      <ul class="nav navbar-nav">
-        <li><a href="#about">About</a></li>
-        <li><a href="#contact">Contact</a></li>
-      </ul>
-      <ul class="nav navbar-nav navbar-right">
-        <li><a href="#">This should not jump to the left when the modal is shown.</a></li>
-      </ul>
-    </div><!--/.nav-collapse -->
+<nav class="navbar navbar-dark bg-inverse navbar-static-top">
+  <button class="navbar-toggler hidden-sm-up" type="button" data-toggle="collapse" data-target="#exCollapsingNavbar2">
+    &#9776;
+  </button>
+  <div class="collapse navbar-toggleable-xs" id="exCollapsingNavbar2">
+    <a class="navbar-brand" href="#">This shouldn't jump!</a>
+    <ul class="nav navbar-nav">
+      <li class="nav-item active">
+        <a class="nav-link" href="#">Home <span class="sr-only">(current)</span></a>
+      </li>
+      <li class="nav-item">
+        <a class="nav-link" href="#">Features</a>
+      </li>
+      <li class="nav-item">
+        <a class="nav-link" href="#">Pricing</a>
+      </li>
+      <li class="nav-item">
+        <a class="nav-link" href="#">About</a>
+      </li>
+    </ul>
   </div>
 </nav>
 
-<div class="container">
+<div class="container m-t-lg">
 
   <div class="page-header">
     <h1>Modal <small>Bootstrap Visual Test</small></h1>
@@ -67,7 +67,7 @@
           <p>Duis mollis, est non commodo luctus, nisi erat porttitor ligula.</p>
 
           <h4>Popover in a modal</h4>
-          <p>This <a href="#" role="button" class="btn btn-default js-popover" title="A Title" data-content="And here's some amazing content. It's very engaging. right?" data-placement="left">button</a> should trigger a popover on click.</p>
+          <p>This <a href="#" role="button" class="btn btn-primary js-popover" title="A Title" data-content="And here's some amazing content. It's very engaging. right?" data-placement="left">button</a> should trigger a popover on click.</p>
 
           <h4>Tooltips in a modal</h4>
           <p><a href="#" class="js-tooltip" title="Tooltip">This link</a> and <a href="#" class="js-tooltip" title="Tooltip">that link</a> should have tooltips on hover.</p>
@@ -141,10 +141,13 @@
 
 <!-- JavaScript Includes -->
 <script src="../vendor/jquery.min.js"></script>
+<script src="../vendor/tether.min.js"></script>
 
 <script src="../../dist/util.js"></script>
 <script src="../../dist/modal.js"></script>
 <script src="../../dist/collapse.js"></script>
+<script src="../../dist/tooltip.js"></script>
+<script src="../../dist/popover.js"></script>
 
 <!-- <script src="../../transition.js"></script>
 <script src="../../tooltip.js"></script>
@@ -153,11 +156,11 @@
 <!-- JavaScript Test -->
 <script>
 $(function () {
-  // $('.js-popover').popover()
-  // $('.js-tooltip').tooltip()
-  // $('#tall-toggle').click(function () {
-  //   $('#tall').toggle()
-  // })
+  $('.js-popover').popover()
+  $('.js-tooltip').tooltip()
+  $('#tall-toggle').click(function () {
+    $('#tall').toggle()
+  })
 })
 </script>