address https://github.com/twbs/bootstrap/pull/16135

4 files changed, 112 insertions, 15 deletions

diff --git a/js/dist/scrollspy.js b/js/dist/scrollspy.js
index a748f7782..69fc579ed 100644
--- a/js/dist/scrollspy.js
+++ b/js/dist/scrollspy.js
@@ -27,7 +27,8 @@ var ScrollSpy = (function ($) {
   var JQUERY_NO_CONFLICT = $.fn[NAME];
 
   var Default = {
-    offset: 10
+    offset: 10,
+    method: 'auto'
   };
 
   var Event = {
@@ -48,6 +49,11 @@ var ScrollSpy = (function ($) {
     LI: 'li'
   };
 
+  var OffsetMethod = {
+    OFFSET: 'offset',
+    POSITION: 'position'
+  };
+
   /**
    * ------------------------------------------------------------------------
    * Class Definition
@@ -81,13 +87,11 @@ var ScrollSpy = (function ($) {
       value: function refresh() {
         var _this = this;
 
-        var offsetMethod = 'offset';
-        var offsetBase = 0;
+        var autoMethod = this._scrollElement !== this._scrollElement.window ? OffsetMethod.POSITION : OffsetMethod.OFFSET;
 
-        if (this._scrollElement !== this._scrollElement.window) {
-          offsetMethod = 'position';
-          offsetBase = this._getScrollTop();
-        }
+        var offsetMethod = this._config.method === 'auto' ? autoMethod : this._config.method;
+
+        var offsetBase = offsetMethod === OffsetMethod.POSITION ? this._getScrollTop() : 0;
 
         this._offsets = [];
         this._targets = [];
diff --git a/js/dist/scrollspy.js.map b/js/dist/scrollspy.js.map
index 9a134b521..98292c7fd 100644
--- a/js/dist/scrollspy.js.map
+++ b/js/dist/scrollspy.js.map
@@ -1 +1 @@
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Util from './util'\n\n\n/**\n * --------------------------------------------------------------------------\n * Bootstrap (v4.0.0): scrollspy.js\n * Licensed under MIT (https://github.com/twbs/bootstrap/blob/master/LICENSE)\n * --------------------------------------------------------------------------\n */\n\nconst ScrollSpy = (($) => {\n\n\n  /**\n   * ------------------------------------------------------------------------\n   * Constants\n   * ------------------------------------------------------------------------\n   */\n\n  const NAME               = 'scrollspy'\n  const VERSION            = '4.0.0'\n  const DATA_KEY           = 'bs.scrollspy'\n  const EVENT_KEY          = `.${DATA_KEY}`\n  const DATA_API_KEY       = '.data-api'\n  const JQUERY_NO_CONFLICT = $.fn[NAME]\n\n  const Default = {\n    offset : 10\n  }\n\n  const Event = {\n    ACTIVATE      : `activate${EVENT_KEY}`,\n    SCROLL        : `scroll${EVENT_KEY}`,\n    LOAD_DATA_API : `load${EVENT_KEY}${DATA_API_KEY}`\n  }\n\n  const ClassName = {\n    DROPDOWN_MENU : 'dropdown-menu',\n    ACTIVE        : 'active'\n  }\n\n  const Selector = {\n    DATA_SPY    : '[data-spy=\"scroll\"]',\n    ACTIVE      : '.active',\n    LI_DROPDOWN : 'li.dropdown',\n    LI          : 'li'\n  }\n\n\n  /**\n   * ------------------------------------------------------------------------\n   * Class Definition\n   * ------------------------------------------------------------------------\n   */\n\n  class ScrollSpy {\n\n    constructor(element, config) {\n      this._element       = element\n      this._scrollElement = element.tagName === 'BODY' ? window : element\n      this._config        = $.extend({}, Default, config)\n      this._selector      = `${this._config.target || ''} .nav li > a`\n      this._offsets       = []\n      this._targets       = []\n      this._activeTarget  = null\n      this._scrollHeight  = 0\n\n      $(this._scrollElement).on(Event.SCROLL, $.proxy(this._process, this))\n\n      this.refresh()\n      this._process()\n    }\n\n\n    // getters\n\n    static get VERSION() {\n      return VERSION\n    }\n\n    static get Default() {\n      return Default\n    }\n\n\n    // public\n\n    refresh() {\n      let offsetMethod = 'offset'\n      let offsetBase   = 0\n\n      if (this._scrollElement !== this._scrollElement.window) {\n        offsetMethod = 'position'\n        offsetBase   = this._getScrollTop()\n      }\n\n      this._offsets = []\n      this._targets = []\n\n      this._scrollHeight = this._getScrollHeight()\n\n      let targets = $.makeArray($(this._selector))\n\n      targets\n        .map((element) => {\n          let target\n          let targetSelector = Util.getSelectorFromElement(element)\n\n          if (targetSelector) {\n            target = $(targetSelector)[0]\n          }\n\n          if (target && (target.offsetWidth || target.offsetHeight)) {\n            // todo (fat): remove sketch reliance on jQuery position/offset\n            return [\n              $(target)[offsetMethod]().top + offsetBase,\n              targetSelector\n            ]\n          }\n        })\n        .filter((item)  => item)\n        .sort((a, b)    => a[0] - b[0])\n        .forEach((item) => {\n          this._offsets.push(item[0])\n          this._targets.push(item[1])\n        })\n    }\n\n    dispose() {\n      $.removeData(this._element, DATA_KEY)\n      $(this._scrollElement).off(EVENT_KEY)\n\n      this._element       = null\n      this._scrollElement = null\n      this._config        = null\n      this._selector      = null\n      this._offsets       = null\n      this._targets       = null\n      this._activeTarget  = null\n      this._scrollHeight  = null\n    }\n\n\n    // private\n\n    _getScrollTop() {\n      return this._scrollElement === window ?\n          this._scrollElement.scrollY : this._scrollElement.scrollTop\n    }\n\n    _getScrollHeight() {\n      return this._scrollElement.scrollHeight || Math.max(\n        document.body.scrollHeight,\n        document.documentElement.scrollHeight\n      )\n    }\n\n    _process() {\n      let scrollTop    = this._getScrollTop() + this._config.offset\n      let scrollHeight = this._getScrollHeight()\n      let maxScroll    = this._config.offset\n        + scrollHeight\n        - this._scrollElement.offsetHeight\n\n      if (this._scrollHeight !== scrollHeight) {\n        this.refresh()\n      }\n\n      if (scrollTop >= maxScroll) {\n        let target = this._targets[this._targets.length - 1]\n\n        if (this._activeTarget !== target) {\n          this._activate(target)\n        }\n      }\n\n      if (this._activeTarget && scrollTop < this._offsets[0]) {\n        this._activeTarget = null\n        this._clear()\n        return\n      }\n\n      for (let i = this._offsets.length; i--;) {\n        let isActiveTarget = this._activeTarget !== this._targets[i]\n            && scrollTop >= this._offsets[i]\n            && (this._offsets[i + 1] === undefined ||\n                scrollTop < this._offsets[i + 1])\n\n        if (isActiveTarget) {\n          this._activate(this._targets[i])\n        }\n      }\n    }\n\n    _activate(target) {\n      this._activeTarget = target\n\n      this._clear()\n\n      let selector =\n        `${this._selector}[data-target=\"${target}\"],` +\n        `${this._selector}[href=\"${target}\"]`\n\n      // todo (fat): getting all the raw li's up the tree is not great.\n      let parentListItems = $(selector).parents(Selector.LI)\n\n      for (let i = parentListItems.length; i--;) {\n        $(parentListItems[i]).addClass(ClassName.ACTIVE)\n\n        let itemParent = parentListItems[i].parentNode\n\n        if (itemParent && $(itemParent).hasClass(ClassName.DROPDOWN_MENU)) {\n          let closestDropdown = $(itemParent)\n            .closest(Selector.LI_DROPDOWN)[0]\n          $(closestDropdown).addClass(ClassName.ACTIVE)\n        }\n      }\n\n      $(this._scrollElement).trigger(Event.ACTIVATE, {\n        relatedTarget: target\n      })\n    }\n\n    _clear() {\n      let activeParents = $(this._selector).parentsUntil(\n        this._config.target,\n        Selector.ACTIVE\n      )\n\n      for (let i = activeParents.length; i--;) {\n        $(activeParents[i]).removeClass(ClassName.ACTIVE)\n      }\n    }\n\n\n    // static\n\n    static _jQueryInterface(config) {\n      return this.each(function () {\n        let data    = $(this).data(DATA_KEY)\n        let _config = typeof config === 'object' && config || null\n\n        if (!data) {\n          data = new ScrollSpy(this, _config)\n          $(this).data(DATA_KEY, data)\n        }\n\n        if (typeof config === 'string') {\n          data[config]()\n        }\n      })\n    }\n\n\n  }\n\n\n  /**\n   * ------------------------------------------------------------------------\n   * Data Api implementation\n   * ------------------------------------------------------------------------\n   */\n\n  $(window).on(Event.LOAD_DATA_API, function () {\n    let scrollSpys = $.makeArray($(Selector.DATA_SPY))\n\n    for (let i = scrollSpys.length; i--;) {\n      let $spy = $(scrollSpys[i])\n      ScrollSpy._jQueryInterface.call($spy, $spy.data())\n    }\n  })\n\n\n  /**\n   * ------------------------------------------------------------------------\n   * jQuery\n   * ------------------------------------------------------------------------\n   */\n\n  $.fn[NAME]             = ScrollSpy._jQueryInterface\n  $.fn[NAME].Constructor = ScrollSpy\n  $.fn[NAME].noConflict  = function () {\n    $.fn[NAME] = JQUERY_NO_CONFLICT\n    return ScrollSpy._jQueryInterface\n  }\n\n  return ScrollSpy\n\n})(jQuery)\n\nexport default ScrollSpy\n"]}
\ No newline at end of file
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Util from './util'\n\n\n/**\n * --------------------------------------------------------------------------\n * Bootstrap (v4.0.0): scrollspy.js\n * Licensed under MIT (https://github.com/twbs/bootstrap/blob/master/LICENSE)\n * --------------------------------------------------------------------------\n */\n\nconst ScrollSpy = (($) => {\n\n\n  /**\n   * ------------------------------------------------------------------------\n   * Constants\n   * ------------------------------------------------------------------------\n   */\n\n  const NAME               = 'scrollspy'\n  const VERSION            = '4.0.0'\n  const DATA_KEY           = 'bs.scrollspy'\n  const EVENT_KEY          = `.${DATA_KEY}`\n  const DATA_API_KEY       = '.data-api'\n  const JQUERY_NO_CONFLICT = $.fn[NAME]\n\n  const Default = {\n    offset : 10,\n    method : 'auto'\n  }\n\n  const Event = {\n    ACTIVATE      : `activate${EVENT_KEY}`,\n    SCROLL        : `scroll${EVENT_KEY}`,\n    LOAD_DATA_API : `load${EVENT_KEY}${DATA_API_KEY}`\n  }\n\n  const ClassName = {\n    DROPDOWN_MENU : 'dropdown-menu',\n    ACTIVE        : 'active'\n  }\n\n  const Selector = {\n    DATA_SPY    : '[data-spy=\"scroll\"]',\n    ACTIVE      : '.active',\n    LI_DROPDOWN : 'li.dropdown',\n    LI          : 'li'\n  }\n\n  const OffsetMethod = {\n    OFFSET   : 'offset',\n    POSITION : 'position'\n  }\n\n\n  /**\n   * ------------------------------------------------------------------------\n   * Class Definition\n   * ------------------------------------------------------------------------\n   */\n\n  class ScrollSpy {\n\n    constructor(element, config) {\n      this._element       = element\n      this._scrollElement = element.tagName === 'BODY' ? window : element\n      this._config        = $.extend({}, Default, config)\n      this._selector      = `${this._config.target || ''} .nav li > a`\n      this._offsets       = []\n      this._targets       = []\n      this._activeTarget  = null\n      this._scrollHeight  = 0\n\n      $(this._scrollElement).on(Event.SCROLL, $.proxy(this._process, this))\n\n      this.refresh()\n      this._process()\n    }\n\n\n    // getters\n\n    static get VERSION() {\n      return VERSION\n    }\n\n    static get Default() {\n      return Default\n    }\n\n\n    // public\n\n    refresh() {\n      let autoMethod = this._scrollElement !== this._scrollElement.window ?\n        OffsetMethod.POSITION : OffsetMethod.OFFSET\n\n      let offsetMethod = this._config.method === 'auto' ?\n        autoMethod : this._config.method\n\n      let offsetBase = offsetMethod === OffsetMethod.POSITION ?\n        this._getScrollTop() : 0\n\n      this._offsets = []\n      this._targets = []\n\n      this._scrollHeight = this._getScrollHeight()\n\n      let targets = $.makeArray($(this._selector))\n\n      targets\n        .map((element) => {\n          let target\n          let targetSelector = Util.getSelectorFromElement(element)\n\n          if (targetSelector) {\n            target = $(targetSelector)[0]\n          }\n\n          if (target && (target.offsetWidth || target.offsetHeight)) {\n            // todo (fat): remove sketch reliance on jQuery position/offset\n            return [\n              $(target)[offsetMethod]().top + offsetBase,\n              targetSelector\n            ]\n          }\n        })\n        .filter((item)  => item)\n        .sort((a, b)    => a[0] - b[0])\n        .forEach((item) => {\n          this._offsets.push(item[0])\n          this._targets.push(item[1])\n        })\n    }\n\n    dispose() {\n      $.removeData(this._element, DATA_KEY)\n      $(this._scrollElement).off(EVENT_KEY)\n\n      this._element       = null\n      this._scrollElement = null\n      this._config        = null\n      this._selector      = null\n      this._offsets       = null\n      this._targets       = null\n      this._activeTarget  = null\n      this._scrollHeight  = null\n    }\n\n\n    // private\n\n    _getScrollTop() {\n      return this._scrollElement === window ?\n          this._scrollElement.scrollY : this._scrollElement.scrollTop\n    }\n\n    _getScrollHeight() {\n      return this._scrollElement.scrollHeight || Math.max(\n        document.body.scrollHeight,\n        document.documentElement.scrollHeight\n      )\n    }\n\n    _process() {\n      let scrollTop    = this._getScrollTop() + this._config.offset\n      let scrollHeight = this._getScrollHeight()\n      let maxScroll    = this._config.offset\n        + scrollHeight\n        - this._scrollElement.offsetHeight\n\n      if (this._scrollHeight !== scrollHeight) {\n        this.refresh()\n      }\n\n      if (scrollTop >= maxScroll) {\n        let target = this._targets[this._targets.length - 1]\n\n        if (this._activeTarget !== target) {\n          this._activate(target)\n        }\n      }\n\n      if (this._activeTarget && scrollTop < this._offsets[0]) {\n        this._activeTarget = null\n        this._clear()\n        return\n      }\n\n      for (let i = this._offsets.length; i--;) {\n        let isActiveTarget = this._activeTarget !== this._targets[i]\n            && scrollTop >= this._offsets[i]\n            && (this._offsets[i + 1] === undefined ||\n                scrollTop < this._offsets[i + 1])\n\n        if (isActiveTarget) {\n          this._activate(this._targets[i])\n        }\n      }\n    }\n\n    _activate(target) {\n      this._activeTarget = target\n\n      this._clear()\n\n      let selector =\n        `${this._selector}[data-target=\"${target}\"],` +\n        `${this._selector}[href=\"${target}\"]`\n\n      // todo (fat): getting all the raw li's up the tree is not great.\n      let parentListItems = $(selector).parents(Selector.LI)\n\n      for (let i = parentListItems.length; i--;) {\n        $(parentListItems[i]).addClass(ClassName.ACTIVE)\n\n        let itemParent = parentListItems[i].parentNode\n\n        if (itemParent && $(itemParent).hasClass(ClassName.DROPDOWN_MENU)) {\n          let closestDropdown = $(itemParent)\n            .closest(Selector.LI_DROPDOWN)[0]\n          $(closestDropdown).addClass(ClassName.ACTIVE)\n        }\n      }\n\n      $(this._scrollElement).trigger(Event.ACTIVATE, {\n        relatedTarget: target\n      })\n    }\n\n    _clear() {\n      let activeParents = $(this._selector).parentsUntil(\n        this._config.target,\n        Selector.ACTIVE\n      )\n\n      for (let i = activeParents.length; i--;) {\n        $(activeParents[i]).removeClass(ClassName.ACTIVE)\n      }\n    }\n\n\n    // static\n\n    static _jQueryInterface(config) {\n      return this.each(function () {\n        let data    = $(this).data(DATA_KEY)\n        let _config = typeof config === 'object' && config || null\n\n        if (!data) {\n          data = new ScrollSpy(this, _config)\n          $(this).data(DATA_KEY, data)\n        }\n\n        if (typeof config === 'string') {\n          data[config]()\n        }\n      })\n    }\n\n\n  }\n\n\n  /**\n   * ------------------------------------------------------------------------\n   * Data Api implementation\n   * ------------------------------------------------------------------------\n   */\n\n  $(window).on(Event.LOAD_DATA_API, function () {\n    let scrollSpys = $.makeArray($(Selector.DATA_SPY))\n\n    for (let i = scrollSpys.length; i--;) {\n      let $spy = $(scrollSpys[i])\n      ScrollSpy._jQueryInterface.call($spy, $spy.data())\n    }\n  })\n\n\n  /**\n   * ------------------------------------------------------------------------\n   * jQuery\n   * ------------------------------------------------------------------------\n   */\n\n  $.fn[NAME]             = ScrollSpy._jQueryInterface\n  $.fn[NAME].Constructor = ScrollSpy\n  $.fn[NAME].noConflict  = function () {\n    $.fn[NAME] = JQUERY_NO_CONFLICT\n    return ScrollSpy._jQueryInterface\n  }\n\n  return ScrollSpy\n\n})(jQuery)\n\nexport default ScrollSpy\n"]}
\ No newline at end of file
diff --git a/js/src/scrollspy.js b/js/src/scrollspy.js
index d1be3a45f..3f4a145a1 100644
--- a/js/src/scrollspy.js
+++ b/js/src/scrollspy.js
@@ -25,7 +25,8 @@ const ScrollSpy = (($) => {
   const JQUERY_NO_CONFLICT = $.fn[NAME]
 
   const Default = {
-    offset : 10
+    offset : 10,
+    method : 'auto'
   }
 
   const Event = {
@@ -46,6 +47,11 @@ const ScrollSpy = (($) => {
     LI          : 'li'
   }
 
+  const OffsetMethod = {
+    OFFSET   : 'offset',
+    POSITION : 'position'
+  }
+
 
   /**
    * ------------------------------------------------------------------------
@@ -86,13 +92,14 @@ const ScrollSpy = (($) => {
     // public
 
     refresh() {
-      let offsetMethod = 'offset'
-      let offsetBase   = 0
+      let autoMethod = this._scrollElement !== this._scrollElement.window ?
+        OffsetMethod.POSITION : OffsetMethod.OFFSET
 
-      if (this._scrollElement !== this._scrollElement.window) {
-        offsetMethod = 'position'
-        offsetBase   = this._getScrollTop()
-      }
+      let offsetMethod = this._config.method === 'auto' ?
+        autoMethod : this._config.method
+
+      let offsetBase = offsetMethod === OffsetMethod.POSITION ?
+        this._getScrollTop() : 0
 
       this._offsets = []
       this._targets = []
diff --git a/js/tests/unit/scrollspy.js b/js/tests/unit/scrollspy.js
index bf5fa0bff..bf963b3ab 100644
--- a/js/tests/unit/scrollspy.js
+++ b/js/tests/unit/scrollspy.js
@@ -275,4 +275,90 @@ $(function () {
       .then(function () { return testElementIsActiveAfterScroll('#li-100-1', '#div-100-1') })
   })
 
+  QUnit.test('should allow passed in option offset method: offset', function (assert) {
+      assert.expect(4)
+
+      var testOffsetMethod = function (type) {
+        var deferred = $.Deferred()
+        var navbarHtml =
+            '<nav class="navbar"' + (type === 'data' ? ' id="navbar-offset-method-menu"' : '') + '>'
+          + '<ul class="nav">'
+          + '<li id="li-' + type + 'm-1"><a href="#div-' + type + 'm-1">div 1</a></li>'
+          + '<li id="li-' + type + 'm-2"><a href="#div-' + type + 'm-2">div 2</a></li>'
+          + '<li id="li-' + type + 'm-3"><a href="#div-' + type + 'm-3">div 3</a></li>'
+          + '</ul>'
+          + '</nav>'
+        var contentHtml =
+            '<div class="content"' + (type === 'data' ? ' data-spy="scroll" data-target="#navbar-offset-method-menu" data-offset="0" data-method="offset"' : '') + ' style="position: relative; overflow: auto; height: 100px">'
+          + '<div id="div-' + type + 'm-1" style="position: relative; height: 200px; padding: 0; margin: 0">div 1</div>'
+          + '<div id="div-' + type + 'm-2" style="position: relative; height: 150px; padding: 0; margin: 0">div 2</div>'
+          + '<div id="div-' + type + 'm-3" style="position: relative; height: 250px; padding: 0; margin: 0">div 3</div>'
+          + '</div>'
+
+
+        $(navbarHtml).appendTo('#qunit-fixture')
+        var $content = $(contentHtml)
+          .appendTo('#qunit-fixture')
+
+        if (type === 'js') $content.bootstrapScrollspy({ target: '.navbar', offset: 0, method: 'offset' })
+        else if (type === 'data') $(window).trigger('load.bs.scrollspy.data-api')
+
+        var $target = $('#div-' + type + 'm-2')
+        var scrollspy = $content.data('bs.scrollspy')
+
+        assert.ok(scrollspy._offsets[1] === $target.offset().top, 'offsed method with ' + type + ' option')
+        assert.ok(scrollspy._offsets[1] !== $target.position().top, 'position method with ' + type + ' option')
+
+        deferred.resolve()
+
+        return deferred.promise()
+      }
+
+      $.when(testOffsetMethod('js'))
+        .then(function () { testOffsetMethod('data') })
+    })
+
+    QUnit.test('should allow passed in option offset method: position', function (assert) {
+      assert.expect(4)
+
+      var testOffsetMethod = function (type) {
+        var deferred = $.Deferred()
+        var navbarHtml =
+            '<nav class="navbar"' + (type === 'data' ? ' id="navbar-offset-method-menu"' : '') + '>'
+          + '<ul class="nav">'
+          + '<li id="li-' + type + 'm-1"><a href="#div-' + type + 'm-1">div 1</a></li>'
+          + '<li id="li-' + type + 'm-2"><a href="#div-' + type + 'm-2">div 2</a></li>'
+          + '<li id="li-' + type + 'm-3"><a href="#div-' + type + 'm-3">div 3</a></li>'
+          + '</ul>'
+          + '</nav>'
+        var contentHtml =
+            '<div class="content"' + (type === 'data' ? ' data-spy="scroll" data-target="#navbar-offset-method-menu" data-offset="0" data-method="position"' : '') + ' style="position: relative; overflow: auto; height: 100px">'
+          + '<div id="div-' + type + 'm-1" style="position: relative; height: 200px; padding: 0; margin: 0">div 1</div>'
+          + '<div id="div-' + type + 'm-2" style="position: relative; height: 150px; padding: 0; margin: 0">div 2</div>'
+          + '<div id="div-' + type + 'm-3" style="position: relative; height: 250px; padding: 0; margin: 0">div 3</div>'
+          + '</div>'
+
+
+        $(navbarHtml).appendTo('#qunit-fixture')
+        var $content = $(contentHtml)
+          .appendTo('#qunit-fixture')
+
+        if (type === 'js') $content.bootstrapScrollspy({ target: '.navbar', offset: 0, method: 'position' })
+        else if (type === 'data') $(window).trigger('load.bs.scrollspy.data-api')
+
+        var $target = $('#div-' + type + 'm-2')
+        var scrollspy = $content.data('bs.scrollspy')
+
+        assert.ok(scrollspy._offsets[1] !== $target.offset().top, 'offsed method with ' + type + ' option')
+        assert.ok(scrollspy._offsets[1] === $target.position().top, 'position method with ' + type + ' option')
+
+        deferred.resolve()
+
+        return deferred.promise()
+      }
+
+      $.when(testOffsetMethod('js'))
+        .then(function () { testOffsetMethod('data') })
+    })
+
 })