rewrite collapse unit tests

2 files changed, 1269 insertions, 0 deletions

diff --git a/js/src/collapse/collapse.js b/js/src/collapse/collapse.js
new file mode 100644
index 000000000..671dc3b6c
--- /dev/null
+++ b/js/src/collapse/collapse.js
@@ -0,0 +1,443 @@
+/**
+ * --------------------------------------------------------------------------
+ * Bootstrap (v4.3.1): collapse.js
+ * Licensed under MIT (https://github.com/twbs/bootstrap/blob/master/LICENSE)
+ * --------------------------------------------------------------------------
+ */
+
+import {
+  jQuery as $,
+  TRANSITION_END,
+  emulateTransitionEnd,
+  getSelectorFromElement,
+  getTransitionDurationFromElement,
+  isElement,
+  makeArray,
+  reflow,
+  typeCheckConfig
+} from '../util/index'
+import Data from '../dom/data'
+import EventHandler from '../dom/event-handler'
+import Manipulator from '../dom/manipulator'
+import SelectorEngine from '../dom/selector-engine'
+
+/**
+ * ------------------------------------------------------------------------
+ * Constants
+ * ------------------------------------------------------------------------
+ */
+
+const NAME = 'collapse'
+const VERSION = '4.3.1'
+const DATA_KEY = 'bs.collapse'
+const EVENT_KEY = `.${DATA_KEY}`
+const DATA_API_KEY = '.data-api'
+
+const Default = {
+  toggle: true,
+  parent: ''
+}
+
+const DefaultType = {
+  toggle: 'boolean',
+  parent: '(string|element)'
+}
+
+const Event = {
+  SHOW: `show${EVENT_KEY}`,
+  SHOWN: `shown${EVENT_KEY}`,
+  HIDE: `hide${EVENT_KEY}`,
+  HIDDEN: `hidden${EVENT_KEY}`,
+  CLICK_DATA_API: `click${EVENT_KEY}${DATA_API_KEY}`
+}
+
+const ClassName = {
+  SHOW: 'show',
+  COLLAPSE: 'collapse',
+  COLLAPSING: 'collapsing',
+  COLLAPSED: 'collapsed'
+}
+
+const Dimension = {
+  WIDTH: 'width',
+  HEIGHT: 'height'
+}
+
+const Selector = {
+  ACTIVES: '.show, .collapsing',
+  DATA_TOGGLE: '[data-toggle="collapse"]'
+}
+
+/**
+ * ------------------------------------------------------------------------
+ * Class Definition
+ * ------------------------------------------------------------------------
+ */
+
+class Collapse {
+  constructor(element, config) {
+    this._isTransitioning = false
+    this._element = element
+    this._config = this._getConfig(config)
+    this._triggerArray = makeArray(SelectorEngine.find(
+      `[data-toggle="collapse"][href="#${element.id}"],` +
+      `[data-toggle="collapse"][data-target="#${element.id}"]`
+    ))
+
+    const toggleList = makeArray(SelectorEngine.find(Selector.DATA_TOGGLE))
+    for (let i = 0, len = toggleList.length; i < len; i++) {
+      const elem = toggleList[i]
+      const selector = getSelectorFromElement(elem)
+      const filterElement = makeArray(SelectorEngine.find(selector))
+        .filter(foundElem => foundElem === element)
+
+      if (selector !== null && filterElement.length) {
+        this._selector = selector
+        this._triggerArray.push(elem)
+      }
+    }
+
+    this._parent = this._config.parent ? this._getParent() : null
+
+    if (!this._config.parent) {
+      this._addAriaAndCollapsedClass(this._element, this._triggerArray)
+    }
+
+    if (this._config.toggle) {
+      this.toggle()
+    }
+
+    Data.setData(element, DATA_KEY, this)
+  }
+
+  // Getters
+
+  static get VERSION() {
+    return VERSION
+  }
+
+  static get Default() {
+    return Default
+  }
+
+  // Public
+
+  toggle() {
+    if (this._element.classList.contains(ClassName.SHOW)) {
+      this.hide()
+    } else {
+      this.show()
+    }
+  }
+
+  show() {
+    if (this._isTransitioning ||
+      this._element.classList.contains(ClassName.SHOW)) {
+      return
+    }
+
+    let actives
+    let activesData
+
+    if (this._parent) {
+      actives = makeArray(SelectorEngine.find(Selector.ACTIVES, this._parent))
+        .filter(elem => {
+          if (typeof this._config.parent === 'string') {
+            return elem.getAttribute('data-parent') === this._config.parent
+          }
+
+          return elem.classList.contains(ClassName.COLLAPSE)
+        })
+
+      if (actives.length === 0) {
+        actives = null
+      }
+    }
+
+    const container = SelectorEngine.findOne(this._selector)
+    if (actives) {
+      const tempActiveData = actives.filter(elem => container !== elem)
+      activesData = tempActiveData[0] ? Data.getData(tempActiveData[0], DATA_KEY) : null
+
+      if (activesData && activesData._isTransitioning) {
+        return
+      }
+    }
+
+    const startEvent = EventHandler.trigger(this._element, Event.SHOW)
+    if (startEvent.defaultPrevented) {
+      return
+    }
+
+    if (actives) {
+      actives.forEach(elemActive => {
+        if (container !== elemActive) {
+          Collapse._collapseInterface(elemActive, 'hide')
+        }
+
+        if (!activesData) {
+          Data.setData(elemActive, DATA_KEY, null)
+        }
+      })
+    }
+
+    const dimension = this._getDimension()
+
+    this._element.classList.remove(ClassName.COLLAPSE)
+    this._element.classList.add(ClassName.COLLAPSING)
+
+    this._element.style[dimension] = 0
+
+    if (this._triggerArray.length) {
+      this._triggerArray.forEach(element => {
+        element.classList.remove(ClassName.COLLAPSED)
+        element.setAttribute('aria-expanded', true)
+      })
+    }
+
+    this.setTransitioning(true)
+
+    const complete = () => {
+      this._element.classList.remove(ClassName.COLLAPSING)
+      this._element.classList.add(ClassName.COLLAPSE)
+      this._element.classList.add(ClassName.SHOW)
+
+      this._element.style[dimension] = ''
+
+      this.setTransitioning(false)
+
+      EventHandler.trigger(this._element, Event.SHOWN)
+    }
+
+    const capitalizedDimension = dimension[0].toUpperCase() + dimension.slice(1)
+    const scrollSize = `scroll${capitalizedDimension}`
+    const transitionDuration = getTransitionDurationFromElement(this._element)
+
+    EventHandler.one(this._element, TRANSITION_END, complete)
+
+    emulateTransitionEnd(this._element, transitionDuration)
+    this._element.style[dimension] = `${this._element[scrollSize]}px`
+  }
+
+  hide() {
+    if (this._isTransitioning ||
+      !this._element.classList.contains(ClassName.SHOW)) {
+      return
+    }
+
+    const startEvent = EventHandler.trigger(this._element, Event.HIDE)
+    if (startEvent.defaultPrevented) {
+      return
+    }
+
+    const dimension = this._getDimension()
+
+    this._element.style[dimension] = `${this._element.getBoundingClientRect()[dimension]}px`
+
+    reflow(this._element)
+
+    this._element.classList.add(ClassName.COLLAPSING)
+    this._element.classList.remove(ClassName.COLLAPSE)
+    this._element.classList.remove(ClassName.SHOW)
+
+    const triggerArrayLength = this._triggerArray.length
+    if (triggerArrayLength > 0) {
+      for (let i = 0; i < triggerArrayLength; i++) {
+        const trigger = this._triggerArray[i]
+        const selector = getSelectorFromElement(trigger)
+
+        if (selector !== null) {
+          const elem = SelectorEngine.findOne(selector)
+
+          if (!elem.classList.contains(ClassName.SHOW)) {
+            trigger.classList.add(ClassName.COLLAPSED)
+            trigger.setAttribute('aria-expanded', false)
+          }
+        }
+      }
+    }
+
+    this.setTransitioning(true)
+
+    const complete = () => {
+      this.setTransitioning(false)
+      this._element.classList.remove(ClassName.COLLAPSING)
+      this._element.classList.add(ClassName.COLLAPSE)
+      EventHandler.trigger(this._element, Event.HIDDEN)
+    }
+
+    this._element.style[dimension] = ''
+    const transitionDuration = getTransitionDurationFromElement(this._element)
+
+    EventHandler.one(this._element, TRANSITION_END, complete)
+    emulateTransitionEnd(this._element, transitionDuration)
+  }
+
+  setTransitioning(isTransitioning) {
+    this._isTransitioning = isTransitioning
+  }
+
+  dispose() {
+    Data.removeData(this._element, DATA_KEY)
+
+    this._config = null
+    this._parent = null
+    this._element = null
+    this._triggerArray = null
+    this._isTransitioning = null
+  }
+
+  // Private
+
+  _getConfig(config) {
+    config = {
+      ...Default,
+      ...config
+    }
+    config.toggle = Boolean(config.toggle) // Coerce string values
+    typeCheckConfig(NAME, config, DefaultType)
+    return config
+  }
+
+  _getDimension() {
+    const hasWidth = this._element.classList.contains(Dimension.WIDTH)
+    return hasWidth ? Dimension.WIDTH : Dimension.HEIGHT
+  }
+
+  _getParent() {
+    let { parent } = this._config
+
+    if (isElement(parent)) {
+      // it's a jQuery object
+      if (typeof parent.jquery !== 'undefined' || typeof parent[0] !== 'undefined') {
+        parent = parent[0]
+      }
+    } else {
+      parent = SelectorEngine.findOne(parent)
+    }
+
+    const selector = `[data-toggle="collapse"][data-parent="${parent}"]`
+
+    makeArray(SelectorEngine.find(selector, parent))
+      .forEach(element => {
+        const selector = getSelectorFromElement(element)
+        const selected = selector ? SelectorEngine.findOne(selector) : null
+
+        this._addAriaAndCollapsedClass(
+          selected,
+          [element]
+        )
+      })
+
+    return parent
+  }
+
+  _addAriaAndCollapsedClass(element, triggerArray) {
+    if (element) {
+      const isOpen = element.classList.contains(ClassName.SHOW)
+
+      if (triggerArray.length) {
+        triggerArray.forEach(elem => {
+          if (isOpen) {
+            elem.classList.remove(ClassName.COLLAPSED)
+          } else {
+            elem.classList.add(ClassName.COLLAPSED)
+          }
+
+          elem.setAttribute('aria-expanded', isOpen)
+        })
+      }
+    }
+  }
+
+  // Static
+
+  static _collapseInterface(element, config) {
+    let data = Data.getData(element, DATA_KEY)
+    const _config = {
+      ...Default,
+      ...Manipulator.getDataAttributes(element),
+      ...typeof config === 'object' && config ? config : {}
+    }
+
+    if (!data && _config.toggle && /show|hide/.test(config)) {
+      _config.toggle = false
+    }
+
+    if (!data) {
+      data = new Collapse(element, _config)
+    }
+
+    if (typeof config === 'string') {
+      if (typeof data[config] === 'undefined') {
+        throw new TypeError(`No method named "${config}"`)
+      }
+
+      data[config]()
+    }
+  }
+
+  static _jQueryInterface(config) {
+    return this.each(function () {
+      Collapse._collapseInterface(this, config)
+    })
+  }
+
+  static _getInstance(element) {
+    return Data.getData(element, DATA_KEY)
+  }
+}
+
+/**
+ * ------------------------------------------------------------------------
+ * Data Api implementation
+ * ------------------------------------------------------------------------
+ */
+
+EventHandler.on(document, Event.CLICK_DATA_API, Selector.DATA_TOGGLE, function (event) {
+  // preventDefault only for <a> elements (which change the URL) not inside the collapsible element
+  if (event.target.tagName === 'A') {
+    event.preventDefault()
+  }
+
+  const triggerData = Manipulator.getDataAttributes(this)
+  const selector = getSelectorFromElement(this)
+  const selectorElements = makeArray(SelectorEngine.find(selector))
+
+  selectorElements.forEach(element => {
+    const data = Data.getData(element, DATA_KEY)
+    let config
+    if (data) {
+      // update parent attribute
+      if (data._parent === null && typeof triggerData.parent === 'string') {
+        data._config.parent = triggerData.parent
+        data._parent = data._getParent()
+      }
+
+      config = 'toggle'
+    } else {
+      config = triggerData
+    }
+
+    Collapse._collapseInterface(element, config)
+  })
+})
+
+/**
+ * ------------------------------------------------------------------------
+ * jQuery
+ * ------------------------------------------------------------------------
+ * add .collapse to jQuery only if jQuery is present
+ */
+/* istanbul ignore if */
+if (typeof $ !== 'undefined') {
+  const JQUERY_NO_CONFLICT = $.fn[NAME]
+  $.fn[NAME] = Collapse._jQueryInterface
+  $.fn[NAME].Constructor = Collapse
+  $.fn[NAME].noConflict = () => {
+    $.fn[NAME] = JQUERY_NO_CONFLICT
+    return Collapse._jQueryInterface
+  }
+}
+
+export default Collapse
diff --git a/js/src/collapse/collapse.spec.js b/js/src/collapse/collapse.spec.js
new file mode 100644
index 000000000..731b4a25f
--- /dev/null
+++ b/js/src/collapse/collapse.spec.js
@@ -0,0 +1,826 @@
+import Collapse from './collapse'
+import EventHandler from '../dom/event-handler'
+import { makeArray } from '../util/index'
+
+/** Test helpers */
+import { getFixture, clearFixture, jQueryMock } from '../../tests/helpers/fixture'
+
+describe('Collapse', () => {
+  let fixtureEl
+
+  beforeAll(() => {
+    fixtureEl = getFixture()
+  })
+
+  afterEach(() => {
+    clearFixture()
+  })
+
+  describe('VERSION', () => {
+    it('should return plugin version', () => {
+      expect(Collapse.VERSION).toEqual(jasmine.any(String))
+    })
+  })
+
+  describe('Default', () => {
+    it('should return plugin default config', () => {
+      expect(Collapse.Default).toEqual(jasmine.any(Object))
+    })
+  })
+
+  describe('constructor', () => {
+    it('should allow jquery object in parent config', () => {
+      fixtureEl.innerHTML = [
+        '<div class="my-collapse">',
+        '  <div class="item">',
+        '    <a data-toggle="collapse" href="#">Toggle item</a>',
+        '    <div class="collapse">Lorem ipsum</div>',
+        '  </div>',
+        '</div>'
+      ].join('')
+
+      const collapseEl = fixtureEl.querySelector('div.collapse')
+      const myCollapseEl = fixtureEl.querySelector('.my-collapse')
+      const fakejQueryObject = {
+        0: myCollapseEl
+      }
+      const collapse = new Collapse(collapseEl, {
+        parent: fakejQueryObject
+      })
+
+      expect(collapse._config.parent).toEqual(fakejQueryObject)
+      expect(collapse._getParent()).toEqual(myCollapseEl)
+    })
+
+    it('should allow non jquery object in parent config', () => {
+      fixtureEl.innerHTML = [
+        '<div class="my-collapse">',
+        '  <div class="item">',
+        '    <a data-toggle="collapse" href="#">Toggle item</a>',
+        '    <div class="collapse">Lorem ipsum</div>',
+        '  </div>',
+        '</div>'
+      ].join('')
+
+      const collapseEl = fixtureEl.querySelector('div.collapse')
+      const myCollapseEl = fixtureEl.querySelector('.my-collapse')
+      const collapse = new Collapse(collapseEl, {
+        parent: myCollapseEl
+      })
+
+      expect(collapse._config.parent).toEqual(myCollapseEl)
+    })
+
+    it('should allow string selector in parent config', () => {
+      fixtureEl.innerHTML = [
+        '<div class="my-collapse">',
+        '  <div class="item">',
+        '    <a data-toggle="collapse" href="#">Toggle item</a>',
+        '    <div class="collapse">Lorem ipsum</div>',
+        '  </div>',
+        '</div>'
+      ].join('')
+
+      const collapseEl = fixtureEl.querySelector('div.collapse')
+      const myCollapseEl = fixtureEl.querySelector('.my-collapse')
+      const collapse = new Collapse(collapseEl, {
+        parent: 'div.my-collapse'
+      })
+
+      expect(collapse._config.parent).toEqual('div.my-collapse')
+      expect(collapse._getParent()).toEqual(myCollapseEl)
+    })
+  })
+
+  describe('toggle', () => {
+    it('should call show method if show class is not present', () => {
+      fixtureEl.innerHTML = '<div></div>'
+
+      const collapseEl = fixtureEl.querySelector('div')
+      const collapse = new Collapse(collapseEl)
+
+      spyOn(collapse, 'show')
+
+      collapse.toggle()
+
+      expect(collapse.show).toHaveBeenCalled()
+    })
+
+    it('should call hide method if show class is present', () => {
+      fixtureEl.innerHTML = '<div class="show"></div>'
+
+      const collapseEl = fixtureEl.querySelector('.show')
+      const collapse = new Collapse(collapseEl, {
+        toggle: false
+      })
+
+      spyOn(collapse, 'hide')
+
+      collapse.toggle()
+
+      expect(collapse.hide).toHaveBeenCalled()
+    })
+
+    it('should find collapse children if they have collapse class too not only data-parent', done => {
+      fixtureEl.innerHTML = [
+        '<div class="my-collapse">',
+        '  <div class="item">',
+        '    <a data-toggle="collapse" href="#">Toggle item 1</a>',
+        '    <div id="collapse1" class="collapse show">Lorem ipsum 1</div>',
+        '  </div>',
+        '  <div class="item">',
+        '    <a id="triggerCollapse2" data-toggle="collapse" href="#">Toggle item 2</a>',
+        '    <div id="collapse2" class="collapse">Lorem ipsum 2</div>',
+        '  </div>',
+        '</div>'
+      ].join('')
+
+      const parent = fixtureEl.querySelector('.my-collapse')
+      const collapseEl1 = fixtureEl.querySelector('#collapse1')
+      const collapseEl2 = fixtureEl.querySelector('#collapse2')
+
+      const collapseList = makeArray(fixtureEl.querySelectorAll('.collapse'))
+        .map(el => new Collapse(el, {
+          parent,
+          toggle: false
+        }))
+
+      collapseEl2.addEventListener('shown.bs.collapse', () => {
+        expect(collapseEl2.classList.contains('show')).toEqual(true)
+        expect(collapseEl1.classList.contains('show')).toEqual(false)
+        done()
+      })
+
+      collapseList[1].toggle()
+    })
+  })
+
+  describe('show', () => {
+    it('should do nothing if is transitioning', () => {
+      fixtureEl.innerHTML = '<div></div>'
+
+      spyOn(EventHandler, 'trigger')
+
+      const collapseEl = fixtureEl.querySelector('div')
+      const collapse = new Collapse(collapseEl, {
+        toggle: false
+      })
+
+      collapse._isTransitioning = true
+      collapse.show()
+
+      expect(EventHandler.trigger).not.toHaveBeenCalled()
+    })
+
+    it('should do nothing if already shown', () => {
+      fixtureEl.innerHTML = '<div class="show"></div>'
+
+      spyOn(EventHandler, 'trigger')
+
+      const collapseEl = fixtureEl.querySelector('div')
+      const collapse = new Collapse(collapseEl, {
+        toggle: false
+      })
+
+      collapse.show()
+
+      expect(EventHandler.trigger).not.toHaveBeenCalled()
+    })
+
+    it('should show a collapsed element', done => {
+      fixtureEl.innerHTML = '<div class="collapse" style="height: 0px;"></div>'
+
+      const collapseEl = fixtureEl.querySelector('div')
+      const collapse = new Collapse(collapseEl, {
+        toggle: false
+      })
+
+      collapseEl.addEventListener('show.bs.collapse', () => {
+        expect(collapseEl.style.height).toEqual('0px')
+      })
+      collapseEl.addEventListener('shown.bs.collapse', () => {
+        expect(collapseEl.classList.contains('show')).toEqual(true)
+        expect(collapseEl.style.height).toEqual('')
+        done()
+      })
+
+      collapse.show()
+    })
+
+    it('should show a collapsed element on width', done => {
+      fixtureEl.innerHTML = '<div class="collapse width" style="width: 0px;"></div>'
+
+      const collapseEl = fixtureEl.querySelector('div')
+      const collapse = new Collapse(collapseEl, {
+        toggle: false
+      })
+
+      collapseEl.addEventListener('show.bs.collapse', () => {
+        expect(collapseEl.style.width).toEqual('0px')
+      })
+      collapseEl.addEventListener('shown.bs.collapse', () => {
+        expect(collapseEl.classList.contains('show')).toEqual(true)
+        expect(collapseEl.style.width).toEqual('')
+        done()
+      })
+
+      collapse.show()
+    })
+
+    it('should collapse only the first collapse', done => {
+      fixtureEl.innerHTML = [
+        '<div class="card" id="accordion1">',
+        '  <div id="collapse1" class="collapse"/>',
+        '</div>',
+        '<div class="card" id="accordion2">',
+        '  <div id="collapse2" class="collapse show"/>',
+        '</div>'
+      ].join('')
+
+      const el1 = fixtureEl.querySelector('#collapse1')
+      const el2 = fixtureEl.querySelector('#collapse2')
+      const collapse = new Collapse(el1, {
+        toggle: false
+      })
+
+      el1.addEventListener('shown.bs.collapse', () => {
+        expect(el1.classList.contains('show')).toEqual(true)
+        expect(el2.classList.contains('show')).toEqual(true)
+        done()
+      })
+
+      collapse.show()
+    })
+
+    it('should not fire shown when show is prevented', done => {
+      fixtureEl.innerHTML = '<div class="collapse"></div>'
+
+      const collapseEl = fixtureEl.querySelector('div')
+      const collapse = new Collapse(collapseEl, {
+        toggle: false
+      })
+
+      const expectEnd = () => {
+        setTimeout(() => {
+          expect().nothing()
+          done()
+        }, 10)
+      }
+
+      collapseEl.addEventListener('show.bs.collapse', e => {
+        e.preventDefault()
+        expectEnd()
+      })
+
+      collapseEl.addEventListener('shown.bs.collapse', () => {
+        throw new Error('should not fire shown event')
+      })
+
+      collapse.show()
+    })
+  })
+
+  describe('hide', () => {
+    it('should do nothing if is transitioning', () => {
+      fixtureEl.innerHTML = '<div></div>'
+
+      spyOn(EventHandler, 'trigger')
+
+      const collapseEl = fixtureEl.querySelector('div')
+      const collapse = new Collapse(collapseEl, {
+        toggle: false
+      })
+
+      collapse._isTransitioning = true
+      collapse.hide()
+
+      expect(EventHandler.trigger).not.toHaveBeenCalled()
+    })
+
+    it('should do nothing if already shown', () => {
+      fixtureEl.innerHTML = '<div></div>'
+
+      spyOn(EventHandler, 'trigger')
+
+      const collapseEl = fixtureEl.querySelector('div')
+      const collapse = new Collapse(collapseEl, {
+        toggle: false
+      })
+
+      collapse.hide()
+
+      expect(EventHandler.trigger).not.toHaveBeenCalled()
+    })
+
+    it('should hide a collapsed element', done => {
+      fixtureEl.innerHTML = '<div class="collapse show"></div>'
+
+      const collapseEl = fixtureEl.querySelector('div')
+      const collapse = new Collapse(collapseEl, {
+        toggle: false
+      })
+
+      collapseEl.addEventListener('hidden.bs.collapse', () => {
+        expect(collapseEl.classList.contains('show')).toEqual(false)
+        expect(collapseEl.style.height).toEqual('')
+        done()
+      })
+
+      collapse.hide()
+    })
+
+    it('should not fire hidden when hide is prevented', done => {
+      fixtureEl.innerHTML = '<div class="collapse show"></div>'
+
+      const collapseEl = fixtureEl.querySelector('div')
+      const collapse = new Collapse(collapseEl, {
+        toggle: false
+      })
+
+      const expectEnd = () => {
+        setTimeout(() => {
+          expect().nothing()
+          done()
+        }, 10)
+      }
+
+      collapseEl.addEventListener('hide.bs.collapse', e => {
+        e.preventDefault()
+        expectEnd()
+      })
+
+      collapseEl.addEventListener('hidden.bs.collapse', () => {
+        throw new Error('should not fire hidden event')
+      })
+
+      collapse.hide()
+    })
+  })
+
+  describe('dispose', () => {
+    it('should destroy a collapse', () => {
+      fixtureEl.innerHTML = '<div class="collapse show"></div>'
+
+      const collapseEl = fixtureEl.querySelector('div')
+      const collapse = new Collapse(collapseEl, {
+        toggle: false
+      })
+
+      expect(Collapse._getInstance(collapseEl)).toEqual(collapse)
+
+      collapse.dispose()
+
+      expect(Collapse._getInstance(collapseEl)).toEqual(null)
+    })
+  })
+
+  describe('data-api', () => {
+    it('should show multiple collapsed elements', done => {
+      fixtureEl.innerHTML = [
+        '<a role="button" data-toggle="collapse" class="collapsed" href=".multi"></a>',
+        '<div id="collapse1" class="collapse multi"/>',
+        '<div id="collapse2" class="collapse multi"/>'
+      ].join('')
+
+      const trigger = fixtureEl.querySelector('a')
+      const collapse1 = fixtureEl.querySelector('#collapse1')
+      const collapse2 = fixtureEl.querySelector('#collapse2')
+
+      collapse2.addEventListener('shown.bs.collapse', () => {
+        expect(trigger.getAttribute('aria-expanded')).toEqual('true')
+        expect(trigger.classList.contains('collapsed')).toEqual(false)
+        expect(collapse1.classList.contains('show')).toEqual(true)
+        expect(collapse1.classList.contains('show')).toEqual(true)
+        done()
+      })
+
+      trigger.click()
+    })
+
+    it('should hide multiple collapsed elements', done => {
+      fixtureEl.innerHTML = [
+        '<a role="button" data-toggle="collapse" href=".multi"></a>',
+        '<div id="collapse1" class="collapse multi show"/>',
+        '<div id="collapse2" class="collapse multi show"/>'
+      ].join('')
+
+      const trigger = fixtureEl.querySelector('a')
+      const collapse1 = fixtureEl.querySelector('#collapse1')
+      const collapse2 = fixtureEl.querySelector('#collapse2')
+
+      collapse2.addEventListener('hidden.bs.collapse', () => {
+        expect(trigger.getAttribute('aria-expanded')).toEqual('false')
+        expect(trigger.classList.contains('collapsed')).toEqual(true)
+        expect(collapse1.classList.contains('show')).toEqual(false)
+        expect(collapse1.classList.contains('show')).toEqual(false)
+        done()
+      })
+
+      trigger.click()
+    })
+
+    it('should remove "collapsed" class from target when collapse is shown', done => {
+      fixtureEl.innerHTML = [
+        '<a id="link1" role="button" data-toggle="collapse" class="collapsed" href="#" data-target="#test1" />',
+        '<a id="link2" role="button" data-toggle="collapse" class="collapsed" href="#" data-target="#test1" />',
+        '<div id="test1"></div>'
+      ].join('')
+
+      const link1 = fixtureEl.querySelector('#link1')
+      const link2 = fixtureEl.querySelector('#link2')
+      const collapseTest1 = fixtureEl.querySelector('#test1')
+
+      collapseTest1.addEventListener('shown.bs.collapse', () => {
+        expect(link1.getAttribute('aria-expanded')).toEqual('true')
+        expect(link2.getAttribute('aria-expanded')).toEqual('true')
+        expect(link1.classList.contains('collapsed')).toEqual(false)
+        expect(link2.classList.contains('collapsed')).toEqual(false)
+        done()
+      })
+
+      link1.click()
+    })
+
+    it('should add "collapsed" class to target when collapse is hidden', done => {
+      fixtureEl.innerHTML = [
+        '<a id="link1" role="button" data-toggle="collapse" href="#" data-target="#test1" />',
+        '<a id="link2" role="button" data-toggle="collapse" href="#" data-target="#test1" />',
+        '<div id="test1" class="show"></div>'
+      ].join('')
+
+      const link1 = fixtureEl.querySelector('#link1')
+      const link2 = fixtureEl.querySelector('#link2')
+      const collapseTest1 = fixtureEl.querySelector('#test1')
+
+      collapseTest1.addEventListener('hidden.bs.collapse', () => {
+        expect(link1.getAttribute('aria-expanded')).toEqual('false')
+        expect(link2.getAttribute('aria-expanded')).toEqual('false')
+        expect(link1.classList.contains('collapsed')).toEqual(true)
+        expect(link2.classList.contains('collapsed')).toEqual(true)
+        done()
+      })
+
+      link1.click()
+    })
+
+    it('should allow accordion to use children other than card', done => {
+      fixtureEl.innerHTML = [
+        '<div id="accordion">',
+        '  <div class="item">',
+        '    <a id="linkTrigger" data-toggle="collapse" href="#collapseOne" aria-expanded="false" aria-controls="collapseOne"></a>',
+        '    <div id="collapseOne" class="collapse" role="tabpanel" aria-labelledby="headingThree" data-parent="#accordion"></div>',
+        '  </div>',
+        '  <div class="item">',
+        '    <a id="linkTriggerTwo" data-toggle="collapse" href="#collapseTwo" aria-expanded="false" aria-controls="collapseTwo"></a>',
+        '    <div id="collapseTwo" class="collapse show" role="tabpanel" aria-labelledby="headingTwo" data-parent="#accordion"></div>',
+        '  </div>',
+        '</div>'
+      ].join('')
+
+      const trigger = fixtureEl.querySelector('#linkTrigger')
+      const triggerTwo = fixtureEl.querySelector('#linkTriggerTwo')
+      const collapseOne = fixtureEl.querySelector('#collapseOne')
+      const collapseTwo = fixtureEl.querySelector('#collapseTwo')
+
+      collapseOne.addEventListener('shown.bs.collapse', () => {
+        expect(collapseOne.classList.contains('show')).toEqual(true)
+        expect(collapseTwo.classList.contains('show')).toEqual(false)
+
+        collapseTwo.addEventListener('shown.bs.collapse', () => {
+          expect(collapseOne.classList.contains('show')).toEqual(false)
+          expect(collapseTwo.classList.contains('show')).toEqual(true)
+          done()
+        })
+
+        triggerTwo.click()
+      })
+
+      trigger.click()
+    })
+
+    it('should not prevent event for input', done => {
+      fixtureEl.innerHTML = [
+        '<input type="checkbox" data-toggle="collapse" data-target="#collapsediv1" />',
+        '<div id="collapsediv1"></div>'
+      ].join('')
+
+      const target = fixtureEl.querySelector('input')
+      const collapseEl = fixtureEl.querySelector('#collapsediv1')
+
+      collapseEl.addEventListener('shown.bs.collapse', () => {
+        expect(collapseEl.classList.contains('show')).toEqual(true)
+        expect(target.checked).toEqual(true)
+        done()
+      })
+
+      target.click()
+    })
+
+    it('should allow accordion to contain nested elements', done => {
+      fixtureEl.innerHTML = [
+        '<div id="accordion">',
+        '  <div class="row">',
+        '    <div class="col-lg-6">',
+        '      <div class="item">',
+        '        <a id="linkTrigger" data-toggle="collapse" href="#collapseOne" aria-expanded="false" aria-controls="collapseOne"></a>',
+        '        <div id="collapseOne" class="collapse" role="tabpanel" aria-labelledby="headingThree" data-parent="#accordion"></div>',
+        '      </div>',
+        '    </div>',
+        '    <div class="col-lg-6">',
+        '      <div class="item">',
+        '        <a id="linkTriggerTwo" data-toggle="collapse" href="#collapseTwo" aria-expanded="false" aria-controls="collapseTwo"></a>',
+        '        <div id="collapseTwo" class="collapse show" role="tabpanel" aria-labelledby="headingTwo" data-parent="#accordion"></div>',
+        '      </div>',
+        '    </div>',
+        '  </div>',
+        '</div>'
+      ].join('')
+
+      const triggerEl = fixtureEl.querySelector('#linkTrigger')
+      const triggerTwoEl = fixtureEl.querySelector('#linkTriggerTwo')
+      const collapseOneEl = fixtureEl.querySelector('#collapseOne')
+      const collapseTwoEl = fixtureEl.querySelector('#collapseTwo')
+
+      collapseOneEl.addEventListener('shown.bs.collapse', () => {
+        expect(collapseOneEl.classList.contains('show')).toEqual(true)
+        expect(triggerEl.classList.contains('collapsed')).toEqual(false)
+        expect(triggerEl.getAttribute('aria-expanded')).toEqual('true')
+
+        expect(collapseTwoEl.classList.contains('show')).toEqual(false)
+        expect(triggerTwoEl.classList.contains('collapsed')).toEqual(true)
+        expect(triggerTwoEl.getAttribute('aria-expanded')).toEqual('false')
+
+        collapseTwoEl.addEventListener('shown.bs.collapse', () => {
+          expect(collapseOneEl.classList.contains('show')).toEqual(false)
+          expect(triggerEl.classList.contains('collapsed')).toEqual(true)
+          expect(triggerEl.getAttribute('aria-expanded')).toEqual('false')
+
+          expect(collapseTwoEl.classList.contains('show')).toEqual(true)
+          expect(triggerTwoEl.classList.contains('collapsed')).toEqual(false)
+          expect(triggerTwoEl.getAttribute('aria-expanded')).toEqual('true')
+          done()
+        })
+
+        triggerTwoEl.click()
+      })
+
+      triggerEl.click()
+    })
+
+    it('should allow accordion to target multiple elements', done => {
+      fixtureEl.innerHTML = [
+        '<div id="accordion">',
+        '  <a id="linkTriggerOne" data-toggle="collapse" data-target=".collapseOne" href="#" aria-expanded="false" aria-controls="collapseOne"></a>',
+        '  <a id="linkTriggerTwo" data-toggle="collapse" data-target=".collapseTwo" href="#" aria-expanded="false" aria-controls="collapseTwo"></a>',
+        '  <div id="collapseOneOne" class="collapse collapseOne" role="tabpanel" data-parent="#accordion"></div>',
+        '  <div id="collapseOneTwo" class="collapse collapseOne" role="tabpanel" data-parent="#accordion"></div>',
+        '  <div id="collapseTwoOne" class="collapse collapseTwo" role="tabpanel" data-parent="#accordion"></div>',
+        '  <div id="collapseTwoTwo" class="collapse collapseTwo" role="tabpanel" data-parent="#accordion"></div>',
+        '</div>'
+      ].join('')
+
+      const trigger = fixtureEl.querySelector('#linkTriggerOne')
+      const triggerTwo = fixtureEl.querySelector('#linkTriggerTwo')
+      const collapseOneOne = fixtureEl.querySelector('#collapseOneOne')
+      const collapseOneTwo = fixtureEl.querySelector('#collapseOneTwo')
+      const collapseTwoOne = fixtureEl.querySelector('#collapseTwoOne')
+      const collapseTwoTwo = fixtureEl.querySelector('#collapseTwoTwo')
+      const collapsedElements = {
+        one: false,
+        two: false
+      }
+
+      function firstTest() {
+        expect(collapseOneOne.classList.contains('show')).toEqual(true)
+        expect(collapseOneTwo.classList.contains('show')).toEqual(true)
+
+        expect(collapseTwoOne.classList.contains('show')).toEqual(false)
+        expect(collapseTwoTwo.classList.contains('show')).toEqual(false)
+
+        triggerTwo.click()
+      }
+
+      function secondTest() {
+        expect(collapseOneOne.classList.contains('show')).toEqual(false)
+        expect(collapseOneTwo.classList.contains('show')).toEqual(false)
+
+        expect(collapseTwoOne.classList.contains('show')).toEqual(true)
+        expect(collapseTwoTwo.classList.contains('show')).toEqual(true)
+        done()
+      }
+
+      collapseOneOne.addEventListener('shown.bs.collapse', () => {
+        if (collapsedElements.one) {
+          firstTest()
+        } else {
+          collapsedElements.one = true
+        }
+      })
+
+      collapseOneTwo.addEventListener('shown.bs.collapse', () => {
+        if (collapsedElements.one) {
+          firstTest()
+        } else {
+          collapsedElements.one = true
+        }
+      })
+
+      collapseTwoOne.addEventListener('shown.bs.collapse', () => {
+        if (collapsedElements.two) {
+          secondTest()
+        } else {
+          collapsedElements.two = true
+        }
+      })
+
+      collapseTwoTwo.addEventListener('shown.bs.collapse', () => {
+        if (collapsedElements.two) {
+          secondTest()
+        } else {
+          collapsedElements.two = true
+        }
+      })
+
+      trigger.click()
+    })
+
+    it('should collapse accordion children but not nested accordion children', done => {
+      fixtureEl.innerHTML = [
+        '<div id="accordion">',
+        '  <div class="item">',
+        '    <a id="linkTrigger" data-toggle="collapse" href="#collapseOne" aria-expanded="false" aria-controls="collapseOne"></a>',
+        '    <div id="collapseOne" data-parent="#accordion" class="collapse" role="tabpanel" aria-labelledby="headingThree">',
+        '      <div id="nestedAccordion">',
+        '        <div class="item">',
+        '          <a id="nestedLinkTrigger" data-toggle="collapse" href="#nestedCollapseOne" aria-expanded="false" aria-controls="nestedCollapseOne"></a>',
+        '          <div id="nestedCollapseOne" data-parent="#nestedAccordion" class="collapse" role="tabpanel" aria-labelledby="headingThree"></div>',
+        '        </div>',
+        '      </div>',
+        '    </div>',
+        '  </div>',
+        '  <div class="item">',
+        '    <a id="linkTriggerTwo" data-toggle="collapse" href="#collapseTwo" aria-expanded="false" aria-controls="collapseTwo"></a>',
+        '    <div id="collapseTwo" data-parent="#accordion" class="collapse show" role="tabpanel" aria-labelledby="headingTwo"></div>',
+        '  </div>',
+        '</div>'
+      ].join('')
+
+      const trigger = fixtureEl.querySelector('#linkTrigger')
+      const triggerTwo = fixtureEl.querySelector('#linkTriggerTwo')
+      const nestedTrigger = fixtureEl.querySelector('#nestedLinkTrigger')
+      const collapseOne = fixtureEl.querySelector('#collapseOne')
+      const collapseTwo = fixtureEl.querySelector('#collapseTwo')
+      const nestedCollapseOne = fixtureEl.querySelector('#nestedCollapseOne')
+
+      function handlerCollapseOne() {
+        expect(collapseOne.classList.contains('show')).toEqual(true)
+        expect(collapseTwo.classList.contains('show')).toEqual(false)
+        expect(nestedCollapseOne.classList.contains('show')).toEqual(false)
+
+        nestedCollapseOne.addEventListener('shown.bs.collapse', handlerNestedCollapseOne)
+        nestedTrigger.click()
+        collapseOne.removeEventListener('shown.bs.collapse', handlerCollapseOne)
+      }
+
+      function handlerNestedCollapseOne() {
+        expect(collapseOne.classList.contains('show')).toEqual(true)
+        expect(collapseTwo.classList.contains('show')).toEqual(false)
+        expect(nestedCollapseOne.classList.contains('show')).toEqual(true)
+
+        collapseTwo.addEventListener('shown.bs.collapse', () => {
+          expect(collapseOne.classList.contains('show')).toEqual(false)
+          expect(collapseTwo.classList.contains('show')).toEqual(true)
+          expect(nestedCollapseOne.classList.contains('show')).toEqual(true)
+          done()
+        })
+
+        triggerTwo.click()
+        nestedCollapseOne.removeEventListener('shown.bs.collapse', handlerNestedCollapseOne)
+      }
+
+      collapseOne.addEventListener('shown.bs.collapse', handlerCollapseOne)
+      trigger.click()
+    })
+
+    it('should add "collapsed" class and set aria-expanded to triggers only when all the targeted collapse are hidden', done => {
+      fixtureEl.innerHTML = [
+        '<a id="trigger1" role="button" data-toggle="collapse" href="#test1"/>',
+        '<a id="trigger2" role="button" data-toggle="collapse" href="#test2"/>',
+        '<a id="trigger3" role="button" data-toggle="collapse" href=".multi"/>',
+        '<div id="test1" class="multi"/>',
+        '<div id="test2" class="multi"/>'
+      ].join('')
+
+      const trigger1 = fixtureEl.querySelector('#trigger1')
+      const trigger2 = fixtureEl.querySelector('#trigger2')
+      const trigger3 = fixtureEl.querySelector('#trigger3')
+      const target1 = fixtureEl.querySelector('#test1')
+      const target2 = fixtureEl.querySelector('#test2')
+
+      const target2Shown = () => {
+        expect(trigger1.classList.contains('collapsed')).toEqual(false)
+        expect(trigger1.getAttribute('aria-expanded')).toEqual('true')
+
+        expect(trigger2.classList.contains('collapsed')).toEqual(false)
+        expect(trigger2.getAttribute('aria-expanded')).toEqual('true')
+
+        expect(trigger3.classList.contains('collapsed')).toEqual(false)
+        expect(trigger3.getAttribute('aria-expanded')).toEqual('true')
+
+        target2.addEventListener('hidden.bs.collapse', () => {
+          expect(trigger1.classList.contains('collapsed')).toEqual(false)
+          expect(trigger1.getAttribute('aria-expanded')).toEqual('true')
+
+          expect(trigger2.classList.contains('collapsed')).toEqual(true)
+          expect(trigger2.getAttribute('aria-expanded')).toEqual('false')
+
+          expect(trigger3.classList.contains('collapsed')).toEqual(false)
+          expect(trigger3.getAttribute('aria-expanded')).toEqual('true')
+
+          target1.addEventListener('hidden.bs.collapse', () => {
+            expect(trigger1.classList.contains('collapsed')).toEqual(true)
+            expect(trigger1.getAttribute('aria-expanded')).toEqual('false')
+
+            expect(trigger2.classList.contains('collapsed')).toEqual(true)
+            expect(trigger2.getAttribute('aria-expanded')).toEqual('false')
+
+            expect(trigger3.classList.contains('collapsed')).toEqual(true)
+            expect(trigger3.getAttribute('aria-expanded')).toEqual('false')
+            done()
+          })
+
+          trigger1.click()
+        })
+
+        trigger2.click()
+      }
+
+      target2.addEventListener('shown.bs.collapse', target2Shown)
+      trigger3.click()
+    })
+  })
+
+  describe('_jQueryInterface', () => {
+    it('should create a collapse', () => {
+      fixtureEl.innerHTML = '<div></div>'
+
+      const div = fixtureEl.querySelector('div')
+
+      jQueryMock.fn.collapse = Collapse._jQueryInterface
+      jQueryMock.elements = [div]
+
+      jQueryMock.fn.collapse.call(jQueryMock)
+
+      expect(Collapse._getInstance(div)).toBeDefined()
+    })
+
+    it('should not re create a collapse', () => {
+      fixtureEl.innerHTML = '<div></div>'
+
+      const div = fixtureEl.querySelector('div')
+      const collapse = new Collapse(div)
+
+      jQueryMock.fn.collapse = Collapse._jQueryInterface
+      jQueryMock.elements = [div]
+
+      jQueryMock.fn.collapse.call(jQueryMock)
+
+      expect(Collapse._getInstance(div)).toEqual(collapse)
+    })
+
+    it('should throw error on undefined method', () => {
+      fixtureEl.innerHTML = '<div></div>'
+
+      const div = fixtureEl.querySelector('div')
+      const action = 'undefinedMethod'
+
+      jQueryMock.fn.collapse = Collapse._jQueryInterface
+      jQueryMock.elements = [div]
+
+      try {
+        jQueryMock.fn.collapse.call(jQueryMock, action)
+      } catch (error) {
+        expect(error.message).toEqual(`No method named "${action}"`)
+      }
+    })
+  })
+
+  describe('_getInstance', () => {
+    it('should return collapse instance', () => {
+      fixtureEl.innerHTML = '<div></div>'
+
+      const div = fixtureEl.querySelector('div')
+      const collapse = new Collapse(div)
+
+      expect(Collapse._getInstance(div)).toEqual(collapse)
+    })
+
+    it('should return null when there is no collapse instance', () => {
+      fixtureEl.innerHTML = '<div></div>'
+
+      const div = fixtureEl.querySelector('div')
+
+      expect(Collapse._getInstance(div)).toEqual(null)
+    })
+  })
+})