Bootstrap/js/tests/unit/dropdown.spec.js

import Dropdown from '../../src/dropdown'
import EventHandler from '../../src/dom/event-handler'
import { noop } from '../../src/util'

/** Test helpers */
import { clearFixture, createEvent, getFixture, jQueryMock } from '../helpers/fixture'

describe('Dropdown', () => {
  let fixtureEl

  beforeAll(() => {
    fixtureEl = getFixture()
  })

  afterEach(() => {
    clearFixture()
  })

  describe('VERSION', () => {
    it('should return plugin version', () => {
      expect(Dropdown.VERSION).toEqual(jasmine.any(String))
    })
  })

  describe('Default', () => {
    it('should return plugin default config', () => {
      expect(Dropdown.Default).toEqual(jasmine.any(Object))
    })
  })

  describe('DefaultType', () => {
    it('should return plugin default type config', () => {
      expect(Dropdown.DefaultType).toEqual(jasmine.any(Object))
    })
  })

  describe('DATA_KEY', () => {
    it('should return plugin data key', () => {
      expect(Dropdown.DATA_KEY).toEqual('bs.dropdown')
    })
  })

  describe('constructor', () => {
    it('should take care of element either passed as a CSS selector or DOM element', () => {
      fixtureEl.innerHTML = [
        '<div class="dropdown">',
        '  <button class="btn dropdown-toggle" data-bs-toggle="dropdown">Dropdown</button>',
        '  <div class="dropdown-menu">',
        '    <a class="dropdown-item" href="#">Link</a>',
        '  </div>',
        '</div>'
      ].join('')

      const btnDropdown = fixtureEl.querySelector('[data-bs-toggle="dropdown"]')
      const dropdownBySelector = new Dropdown('[data-bs-toggle="dropdown"]')
      const dropdownByElement = new Dropdown(btnDropdown)

      expect(dropdownBySelector._element).toEqual(btnDropdown)
      expect(dropdownByElement._element).toEqual(btnDropdown)
    })

    it('should create offset modifier correctly when offset option is a function', done => {
      fixtureEl.innerHTML = [
        '<div class="dropdown">',
        '  <button class="btn dropdown-toggle" data-bs-toggle="dropdown">Dropdown</button>',
        '  <div class="dropdown-menu">',
        '    <a class="dropdown-item" href="#">Secondary link</a>',
        '  </div>',
        '</div>'
      ].join('')

      const getOffset = jasmine.createSpy('getOffset').and.returnValue([10, 20])
      const btnDropdown = fixtureEl.querySelector('[data-bs-toggle="dropdown"]')
      const dropdown = new Dropdown(btnDropdown, {
        offset: getOffset,
        popperConfig: {
          onFirstUpdate: state => {
            expect(getOffset).toHaveBeenCalledWith({
              popper: state.rects.popper,
              reference: state.rects.reference,
              placement: state.placement
            }, btnDropdown)
            done()
          }
        }
      })
      const offset = dropdown._getOffset()

      expect(typeof offset).toEqual('function')

      dropdown.show()
    })

    it('should create offset modifier correctly when offset option is a string into data attribute', () => {
      fixtureEl.innerHTML = [
        '<div class="dropdown">',
        '  <button class="btn dropdown-toggle" data-bs-toggle="dropdown" data-bs-offset="10,20">Dropdown</button>',
        '  <div class="dropdown-menu">',
        '    <a class="dropdown-item" href="#">Secondary link</a>',
        '  </div>',
        '</div>'
      ].join('')

      const btnDropdown = fixtureEl.querySelector('[data-bs-toggle="dropdown"]')
      const dropdown = new Dropdown(btnDropdown)

      expect(dropdown._getOffset()).toEqual([10, 20])
    })

    it('should allow to pass config to Popper with `popperConfig`', () => {
      fixtureEl.innerHTML = [
        '<div class="dropdown">',
        '  <button class="btn dropdown-toggle" data-bs-toggle="dropdown">Dropdown</button>',
        '  <div class="dropdown-menu">',
        '    <a class="dropdown-item" href="#">Secondary link</a>',
        '  </div>',
        '</div>'
      ].join('')

      const btnDropdown = fixtureEl.querySelector('[data-bs-toggle="dropdown"]')
      const dropdown = new Dropdown(btnDropdown, {
        popperConfig: {
          placement: 'left'
        }
      })

      const popperConfig = dropdown._getPopperConfig()

      expect(popperConfig.placement).toEqual('left')
    })

    it('should allow to pass config to Popper with `popperConfig` as a function', () => {
      fixtureEl.innerHTML = [
        '<div class="dropdown">',
        '  <button class="btn dropdown-toggle" data-bs-toggle="dropdown" data-bs-placement="right" >Dropdown</button>',
        '  <div class="dropdown-menu">',
        '    <a class="dropdown-item" href="#">Secondary link</a>',
        '  </div>',
        '</div>'
      ].join('')

      const btnDropdown = fixtureEl.querySelector('[data-bs-toggle="dropdown"]')
      const getPopperConfig = jasmine.createSpy('getPopperConfig').and.returnValue({ placement: 'left' })
      const dropdown = new Dropdown(btnDropdown, {
        popperConfig: getPopperConfig
      })

      const popperConfig = dropdown._getPopperConfig()

      expect(getPopperConfig).toHaveBeenCalled()
      expect(popperConfig.placement).toEqual('left')
    })
  })

  describe('toggle', () => {
    it('should toggle a dropdown', done => {
      fixtureEl.innerHTML = [
        '<div class="dropdown">',
        '  <button class="btn dropdown-toggle" data-bs-toggle="dropdown" aria-expanded="false">Dropdown</button>',
        '  <div class="dropdown-menu">',
        '    <a class="dropdown-item" href="#">Secondary link</a>',
        '  </div>',
        '</div>'
      ].join('')

      const btnDropdown = fixtureEl.querySelector('[data-bs-toggle="dropdown"]')
      const dropdown = new Dropdown(btnDropdown)

      btnDropdown.addEventListener('shown.bs.dropdown', () => {
        expect(btnDropdown.classList.contains('show')).toEqual(true)
        expect(btnDropdown.getAttribute('aria-expanded')).toEqual('true')
        done()
      })

      dropdown.toggle()
    })

    it('should destroy old popper references on toggle', done => {
      fixtureEl.innerHTML = [
        '<div class="first dropdown">',
        '  <button class="firstBtn btn" data-bs-toggle="dropdown" aria-expanded="false">Dropdown</button>',
        '  <div class="dropdown-menu">',
        '    <a class="dropdown-item" href="#">Secondary link</a>',
        '  </div>',
        '</div>',
        '<div class="second dropdown">',
        '  <button class="secondBtn btn" data-bs-toggle="dropdown" aria-expanded="false">Dropdown</button>',
        '  <div class="dropdown-menu">',
        '    <a class="dropdown-item" href="#">Secondary link</a>',
        '  </div>',
        '</div>'
      ].join('')

      const btnDropdown1 = fixtureEl.querySelector('.firstBtn')
      const btnDropdown2 = fixtureEl.querySelector('.secondBtn')
      const firstDropdownEl = fixtureEl.querySelector('.first')
      const secondDropdownEl = fixtureEl.querySelector('.second')
      const dropdown1 = new Dropdown(btnDropdown1)

      firstDropdownEl.addEventListener('shown.bs.dropdown', () => {
        expect(btnDropdown1.classList.contains('show')).toEqual(true)
        spyOn(dropdown1._popper, 'destroy')
        btnDropdown2.click()
      })

      secondDropdownEl.addEventListener('shown.bs.dropdown', () => setTimeout(() => {
        expect(dropdown1._popper.destroy).toHaveBeenCalled()
        done()
      }))

      dropdown1.toggle()
    })

    it('should toggle a dropdown and add/remove event listener on mobile', done => {
      fixtureEl.innerHTML = [
        '<div class="dropdown">',
        '  <button class="btn dropdown-toggle" data-bs-toggle="dropdown" aria-expanded="false">Dropdown</button>',
        '  <div class="dropdown-menu">',
        '    <a class="dropdown-item" href="#">Secondary link</a>',
        '  </div>',
        '</div>'
      ].join('')

      const defaultValueOnTouchStart = document.documentElement.ontouchstart
      const btnDropdown = fixtureEl.querySelector('[data-bs-toggle="dropdown"]')
      const dropdown = new Dropdown(btnDropdown)

      document.documentElement.ontouchstart = () => {}
      spyOn(EventHandler, 'on')
      spyOn(EventHandler, 'off')

      btnDropdown.addEventListener('shown.bs.dropdown', () => {
        expect(btnDropdown.classList.contains('show')).toEqual(true)
        expect(btnDropdown.getAttribute('aria-expanded')).toEqual('true')
        expect(EventHandler.on).toHaveBeenCalledWith(jasmine.any(Object), 'mouseover', noop)

        dropdown.toggle()
      })

      btnDropdown.addEventListener('hidden.bs.dropdown', () => {
        expect(btnDropdown.classList.contains('show')).toEqual(false)
        expect(btnDropdown.getAttribute('aria-expanded')).toEqual('false')
        expect(EventHandler.off).toHaveBeenCalledWith(jasmine.any(Object), 'mouseover', noop)

        document.documentElement.ontouchstart = defaultValueOnTouchStart
        done()
      })

      dropdown.toggle()
    })

    it('should toggle a dropdown at the right', done => {
      fixtureEl.innerHTML = [
        '<div class="dropdown">',
        '  <button class="btn dropdown-toggle" data-bs-toggle="dropdown" aria-expanded="false">Dropdown</button>',
        '  <div class="dropdown-menu dropdown-menu-end">',
        '    <a class="dropdown-item" href="#">Secondary link</a>',
        '  </div>',
        '</div>'
      ].join('')

      const btnDropdown = fixtureEl.querySelector('[data-bs-toggle="dropdown"]')
      const dropdown = new Dropdown(btnDropdown)

      btnDropdown.addEventListener('shown.bs.dropdown', () => {
        expect(btnDropdown.classList.contains('show')).toEqual(true)
        expect(btnDropdown.getAttribute('aria-expanded')).toEqual('true')
        done()
      })

      dropdown.toggle()
    })

    it('should toggle a dropup', done => {
      fixtureEl.innerHTML = [
        '<div class="dropup">',
        '  <button class="btn dropdown-toggle" data-bs-toggle="dropdown" aria-expanded="false">Dropdown</button>',
        '  <div class="dropdown-menu">',
        '    <a class="dropdown-item" href="#">Secondary link</a>',
        '  </div>',
        '</div>'
      ].join('')

      const btnDropdown = fixtureEl.querySelector('[data-bs-toggle="dropdown"]')
      const dropupEl = fixtureEl.querySelector('.dropup')
      const dropdown = new Dropdown(btnDropdown)

      dropupEl.addEventListener('shown.bs.dropdown', () => {
        expect(btnDropdown.classList.contains('show')).toEqual(true)
        expect(btnDropdown.getAttribute('aria-expanded')).toEqual('true')
        done()
      })

      dropdown.toggle()
    })

    it('should toggle a dropup at the right', done => {
      fixtureEl.innerHTML = [
        '<div class="dropup">',
        '  <button class="btn dropdown-toggle" data-bs-toggle="dropdown" aria-expanded="false">Dropdown</button>',
        '  <div class="dropdown-menu dropdown-menu-end">',
        '    <a class="dropdown-item" href="#">Secondary link</a>',
        '  </div>',
        '</div>'
      ].join('')

      const btnDropdown = fixtureEl.querySelector('[data-bs-toggle="dropdown"]')
      const dropupEl = fixtureEl.querySelector('.dropup')
      const dropdown = new Dropdown(btnDropdown)

      dropupEl.addEventListener('shown.bs.dropdown', () => {
        expect(btnDropdown.classList.contains('show')).toEqual(true)
        expect(btnDropdown.getAttribute('aria-expanded')).toEqual('true')
        done()
      })

      dropdown.toggle()
    })

    it('should toggle a dropend', done => {
      fixtureEl.innerHTML = [
        '<div class="dropend">',
        '  <button class="btn dropdown-toggle" data-bs-toggle="dropdown" aria-expanded="false">Dropdown</button>',
        '  <div class="dropdown-menu">',
        '    <a class="dropdown-item" href="#">Secondary link</a>',
        '  </div>',
        '</div>'
      ].join('')

      const btnDropdown = fixtureEl.querySelector('[data-bs-toggle="dropdown"]')
      const dropendEl = fixtureEl.querySelector('.dropend')
      const dropdown = new Dropdown(btnDropdown)

      dropendEl.addEventListener('shown.bs.dropdown', () => {
        expect(btnDropdown.classList.contains('show')).toEqual(true)
        expect(btnDropdown.getAttribute('aria-expanded')).toEqual('true')
        done()
      })

      dropdown.toggle()
    })

    it('should toggle a dropstart', done => {
      fixtureEl.innerHTML = [
        '<div class="dropstart">',
        '  <button class="btn dropdown-toggle" data-bs-toggle="dropdown" aria-expanded="false">Dropdown</button>',
        '  <div class="dropdown-menu">',
        '    <a class="dropdown-item" href="#">Secondary link</a>',
        '  </div>',
        '</div>'
      ].join('')

      const btnDropdown = fixtureEl.querySelector('[data-bs-toggle="dropdown"]')
      const dropstartEl = fixtureEl.querySelector('.dropstart')
      const dropdown = new Dropdown(btnDropdown)

      dropstartEl.addEventListener('shown.bs.dropdown', () => {
        expect(btnDropdown.classList.contains('show')).toEqual(true)
        expect(btnDropdown.getAttribute('aria-expanded')).toEqual('true')
        done()
      })

      dropdown.toggle()
    })

    it('should toggle a dropdown with parent reference', done => {
      fixtureEl.innerHTML = [
        '<div class="dropdown">',
        '  <button class="btn dropdown-toggle" data-bs-toggle="dropdown" aria-expanded="false">Dropdown</button>',
        '  <div class="dropdown-menu">',
        '    <a class="dropdown-item" href="#">Secondary link</a>',
        '  </div>',
        '</div>'
      ].join('')

      const btnDropdown = fixtureEl.querySelector('[data-bs-toggle="dropdown"]')
      const dropdown = new Dropdown(btnDropdown, {
        reference: 'parent'
      })

      btnDropdown.addEventListener('shown.bs.dropdown', () => {
        expect(btnDropdown.classList.contains('show')).toEqual(true)
        expect(btnDropdown.getAttribute('aria-expanded')).toEqual('true')
        done()
      })

      dropdown.toggle()
    })

    it('should toggle a dropdown with a dom node reference', done => {
      fixtureEl.innerHTML = [
        '<div class="dropdown">',
        '  <button class="btn dropdown-toggle" data-bs-toggle="dropdown" aria-expanded="false">Dropdown</button>',
        '  <div class="dropdown-menu">',
        '    <a class="dropdown-item" href="#">Secondary link</a>',
        '  </div>',
        '</div>'
      ].join('')

      const btnDropdown = fixtureEl.querySelector('[data-bs-toggle="dropdown"]')
      const dropdown = new Dropdown(btnDropdown, {
        reference: fixtureEl
      })

      btnDropdown.addEventListener('shown.bs.dropdown', () => {
        expect(btnDropdown.classList.contains('show')).toEqual(true)
        expect(btnDropdown.getAttribute('aria-expanded')).toEqual('true')
        done()
      })

      dropdown.toggle()
    })

    it('should toggle a dropdown with a jquery object reference', done => {
      fixtureEl.innerHTML = [
        '<div class="dropdown">',
        '  <button class="btn dropdown-toggle" data-bs-toggle="dropdown" aria-expanded="false">Dropdown</button>',
        '  <div class="dropdown-menu">',
        '    <a class="dropdown-item" href="#">Secondary link</a>',
        '  </div>',
        '</div>'
      ].join('')

      const btnDropdown = fixtureEl.querySelector('[data-bs-toggle="dropdown"]')
      const dropdown = new Dropdown(btnDropdown, {
        reference: { 0: fixtureEl, jquery: 'jQuery' }
      })

      btnDropdown.addEventListener('shown.bs.dropdown', () => {
        expect(btnDropdown.classList.contains('show')).toEqual(true)
        expect(btnDropdown.getAttribute('aria-expanded')).toEqual('true')
        done()
      })

      dropdown.toggle()
    })

    it('should toggle a dropdown with a valid virtual element reference', done => {
      fixtureEl.innerHTML = [
        '<div class="dropdown">',
        '  <button class="btn dropdown-toggle visually-hidden" data-bs-toggle="dropdown" aria-expanded="false">Dropdown</button>',
        '  <div class="dropdown-menu">',
        '    <a class="dropdown-item" href="#">Secondary link</a>',
        '  </div>',
        '</div>'
      ].join('')

      const btnDropdown = fixtureEl.querySelector('[data-bs-toggle="dropdown"]')
      const virtualElement = {
        nodeType: 1,
        getBoundingClientRect() {
          return {
            width: 0,
            height: 0,
            top: 0,
            right: 0,
            bottom: 0,
            left: 0
          }
        }
      }

      expect(() => new Dropdown(btnDropdown, {
        reference: {}
      })).toThrowError(TypeError, 'DROPDOWN: Option "reference" provided type "object" without a required "getBoundingClientRect" method.')

      expect(() => new Dropdown(btnDropdown, {
        reference: {
          getBoundingClientRect: 'not-a-function'
        }
      })).toThrowError(TypeError, 'DROPDOWN: Option "reference" provided type "object" without a required "getBoundingClientRect" method.')

      // use onFirstUpdate as Poppers internal update is executed async
      const dropdown = new Dropdown(btnDropdown, {
        reference: virtualElement,
        popperConfig: {
          onFirstUpdate() {
            expect(virtualElement.getBoundingClientRect).toHaveBeenCalled()
            expect(btnDropdown.classList.contains('show')).toEqual(true)
            expect(btnDropdown.getAttribute('aria-expanded')).toEqual('true')
            done()
          }
        }
      })

      spyOn(virtualElement, 'getBoundingClientRect').and.callThrough()

      dropdown.toggle()
    })

    it('should not toggle a dropdown if the element is disabled', done => {
      fixtureEl.innerHTML = [
        '<div class="dropdown">',
        '  <button disabled class="btn dropdown-toggle" data-bs-toggle="dropdown">Dropdown</button>',
        '  <div class="dropdown-menu">',
        '    <a class="dropdown-item" href="#">Secondary link</a>',
        '  </div>',
        '</div>'
      ].join('')

      const btnDropdown = fixtureEl.querySelector('[data-bs-toggle="dropdown"]')
      const dropdown = new Dropdown(btnDropdown)

      btnDropdown.addEventListener('shown.bs.dropdown', () => {
        throw new Error('should not throw shown.bs.dropdown event')
      })

      dropdown.toggle()

      setTimeout(() => {
        expect().nothing()
        done()
      })
    })

    it('should not toggle a dropdown if the element contains .disabled', done => {
      fixtureEl.innerHTML = [
        '<div class="dropdown">',
        '  <button class="btn dropdown-toggle disabled" data-bs-toggle="dropdown">Dropdown</button>',
        '  <div class="dropdown-menu">',
        '    <a class="dropdown-item" href="#">Secondary link</a>',
        '  </div>',
        '</div>'
      ].join('')

      const btnDropdown = fixtureEl.querySelector('[data-bs-toggle="dropdown"]')
      const dropdown = new Dropdown(btnDropdown)

      btnDropdown.addEventListener('shown.bs.dropdown', () => {
        throw new Error('should not throw shown.bs.dropdown event')
      })

      dropdown.toggle()

      setTimeout(() => {
        expect().nothing()
        done()
      })
    })

    it('should not toggle a dropdown if the menu is shown', done => {
      fixtureEl.innerHTML = [
        '<div class="dropdown">',
        '  <button class="btn dropdown-toggle" data-bs-toggle="dropdown">Dropdown</button>',
        '  <div class="dropdown-menu show">',
        '    <a class="dropdown-item" href="#">Secondary link</a>',
        '  </div>',
        '</div>'
      ].join('')

      const btnDropdown = fixtureEl.querySelector('[data-bs-toggle="dropdown"]')
      const dropdown = new Dropdown(btnDropdown)

      btnDropdown.addEventListener('shown.bs.dropdown', () => {
        throw new Error('should not throw shown.bs.dropdown event')
      })

      dropdown.toggle()

      setTimeout(() => {
        expect().nothing()
        done()
      })
    })

    it('should not toggle a dropdown if show event is prevented', done => {
      fixtureEl.innerHTML = [
        '<div class="dropdown">',
        '  <button class="btn dropdown-toggle" data-bs-toggle="dropdown">Dropdown</button>',
        '  <div class="dropdown-menu">',
        '    <a class="dropdown-item" href="#">Secondary link</a>',
        '  </div>',
        '</div>'
      ].join('')

      const btnDropdown = fixtureEl.querySelector('[data-bs-toggle="dropdown"]')
      const dropdown = new Dropdown(btnDropdown)

      btnDropdown.addEventListener('show.bs.dropdown', e => {
        e.preventDefault()
      })

      btnDropdown.addEventListener('shown.bs.dropdown', () => {
        throw new Error('should not throw shown.bs.dropdown event')
      })

      dropdown.toggle()

      setTimeout(() => {
        expect().nothing()
        done()
      })
    })
  })

  describe('show', () => {
    it('should show a dropdown', done => {
      fixtureEl.innerHTML = [
        '<div class="dropdown">',
        '  <button class="btn dropdown-toggle" data-bs-toggle="dropdown">Dropdown</button>',
        '  <div class="dropdown-menu">',
        '    <a class="dropdown-item" href="#">Secondary link</a>',
        '  </div>',
        '</div>'
      ].join('')

      const btnDropdown = fixtureEl.querySelector('[data-bs-toggle="dropdown"]')
      const dropdown = new Dropdown(btnDropdown)

      btnDropdown.addEventListener('shown.bs.dropdown', () => {
        expect(btnDropdown.classList.contains('show')).toEqual(true)
        done()
      })

      dropdown.show()
    })

    it('should not show a dropdown if the element is disabled', done => {
      fixtureEl.innerHTML = [
        '<div class="dropdown">',
        '  <button disabled class="btn dropdown-toggle" data-bs-toggle="dropdown">Dropdown</button>',
        '  <div class="dropdown-menu">',
        '    <a class="dropdown-item" href="#">Secondary link</a>',
        '  </div>',
        '</div>'
      ].join('')

      const btnDropdown = fixtureEl.querySelector('[data-bs-toggle="dropdown"]')
      const dropdown = new Dropdown(btnDropdown)

      btnDropdown.addEventListener('shown.bs.dropdown', () => {
        throw new Error('should not throw shown.bs.dropdown event')
      })

      dropdown.show()

      setTimeout(() => {
        expect().nothing()
        done()
      }, 10)
    })

    it('should not show a dropdown if the element contains .disabled', done => {
      fixtureEl.innerHTML = [
        '<div class="dropdown">',
        '  <button class="btn dropdown-toggle disabled" data-bs-toggle="dropdown">Dropdown</button>',
        '  <div class="dropdown-menu">',
        '    <a class="dropdown-item" href="#">Secondary link</a>',
        '  </div>',
        '</div>'
      ].join('')

      const btnDropdown = fixtureEl.querySelector('[data-bs-toggle="dropdown"]')
      const dropdown = new Dropdown(btnDropdown)

      btnDropdown.addEventListener('shown.bs.dropdown', () => {
        throw new Error('should not throw shown.bs.dropdown event')
      })

      dropdown.show()

      setTimeout(() => {
        expect().nothing()
        done()
      }, 10)
    })

    it('should not show a dropdown if the menu is shown', done => {
      fixtureEl.innerHTML = [
        '<div class="dropdown">',
        '  <button class="btn dropdown-toggle" data-bs-toggle="dropdown">Dropdown</button>',
        '  <div class="dropdown-menu show">',
        '    <a class="dropdown-item" href="#">Secondary link</a>',
        '  </div>',
        '</div>'
      ].join('')

      const btnDropdown = fixtureEl.querySelector('[data-bs-toggle="dropdown"]')
      const dropdown = new Dropdown(btnDropdown)

      btnDropdown.addEventListener('shown.bs.dropdown', () => {
        throw new Error('should not throw shown.bs.dropdown event')
      })

      dropdown.show()

      setTimeout(() => {
        expect().nothing()
        done()
      }, 10)
    })

    it('should not show a dropdown if show event is prevented', done => {
      fixtureEl.innerHTML = [
        '<div class="dropdown">',
        '  <button class="btn dropdown-toggle" data-bs-toggle="dropdown">Dropdown</button>',
        '  <div class="dropdown-menu">',
        '    <a class="dropdown-item" href="#">Secondary link</a>',
        '  </div>',
        '</div>'
      ].join('')

      const btnDropdown = fixtureEl.querySelector('[data-bs-toggle="dropdown"]')
      const dropdown = new Dropdown(btnDropdown)

      btnDropdown.addEventListener('show.bs.dropdown', e => {
        e.preventDefault()
      })

      btnDropdown.addEventListener('shown.bs.dropdown', () => {
        throw new Error('should not throw shown.bs.dropdown event')
      })

      dropdown.show()

      setTimeout(() => {
        expect().nothing()
        done()
      }, 10)
    })
  })

  describe('hide', () => {
    it('should hide a dropdown', done => {
      fixtureEl.innerHTML = [
        '<div class="dropdown">',
        '  <button class="btn dropdown-toggle" data-bs-toggle="dropdown" aria-expanded="true">Dropdown</button>',
        '  <div class="dropdown-menu show">',
        '    <a class="dropdown-item" href="#">Secondary link</a>',
        '  </div>',
        '</div>'
      ].join('')

      const btnDropdown = fixtureEl.querySelector('[data-bs-toggle="dropdown"]')
      const dropdownMenu = fixtureEl.querySelector('.dropdown-menu')
      const dropdown = new Dropdown(btnDropdown)

      btnDropdown.addEventListener('hidden.bs.dropdown', () => {
        expect(dropdownMenu.classList.contains('show')).toEqual(false)
        expect(btnDropdown.getAttribute('aria-expanded')).toEqual('false')
        done()
      })

      dropdown.hide()
    })

    it('should hide a dropdown and destroy popper', done => {
      fixtureEl.innerHTML = [
        '<div class="dropdown">',
        '  <button class="btn dropdown-toggle" data-bs-toggle="dropdown">Dropdown</button>',
        '  <div class="dropdown-menu">',
        '    <a class="dropdown-item" href="#">Secondary link</a>',
        '  </div>',
        '</div>'
      ].join('')

      const btnDropdown = fixtureEl.querySelector('[data-bs-toggle="dropdown"]')
      const dropdown = new Dropdown(btnDropdown)

      btnDropdown.addEventListener('shown.bs.dropdown', () => {
        spyOn(dropdown._popper, 'destroy')
        dropdown.hide()
      })

      btnDropdown.addEventListener('hidden.bs.dropdown', () => {
        expect(dropdown._popper.destroy).toHaveBeenCalled()
        done()
      })

      dropdown.show()
    })

    it('should not hide a dropdown if the element is disabled', done => {
      fixtureEl.innerHTML = [
        '<div class="dropdown">',
        '  <button disabled class="btn dropdown-toggle" data-bs-toggle="dropdown">Dropdown</button>',
        '  <div class="dropdown-menu show">',
        '    <a class="dropdown-item" href="#">Secondary link</a>',
        '  </div>',
        '</div>'
      ].join('')

      const btnDropdown = fixtureEl.querySelector('[data-bs-toggle="dropdown"]')
      const dropdownMenu = fixtureEl.querySelector('.dropdown-menu')
      const dropdown = new Dropdown(btnDropdown)

      btnDropdown.addEventListener('hidden.bs.dropdown', () => {
        throw new Error('should not throw hidden.bs.dropdown event')
      })

      dropdown.hide()

      setTimeout(() => {
        expect(dropdownMenu.classList.contains('show')).toEqual(true)
        done()
      }, 10)
    })

    it('should not hide a dropdown if the element contains .disabled', done => {
      fixtureEl.innerHTML = [
        '<div class="dropdown">',
        '  <button class="btn dropdown-toggle disabled" data-bs-toggle="dropdown">Dropdown</button>',
        '  <div class="dropdown-menu show">',
        '    <a class="dropdown-item" href="#">Secondary link</a>',
        '  </div>',
        '</div>'
      ].join('')

      const btnDropdown = fixtureEl.querySelector('[data-bs-toggle="dropdown"]')
      const dropdownMenu = fixtureEl.querySelector('.dropdown-menu')
      const dropdown = new Dropdown(btnDropdown)

      btnDropdown.addEventListener('hidden.bs.dropdown', () => {
        throw new Error('should not throw hidden.bs.dropdown event')
      })

      dropdown.hide()

      setTimeout(() => {
        expect(dropdownMenu.classList.contains('show')).toEqual(true)
        done()
      }, 10)
    })

    it('should not hide a dropdown if the menu is not shown', done => {
      fixtureEl.innerHTML = [
        '<div class="dropdown">',
        '  <button class="btn dropdown-toggle" data-bs-toggle="dropdown">Dropdown</button>',
        '  <div class="dropdown-menu">',
        '    <a class="dropdown-item" href="#">Secondary link</a>',
        '  </div>',
        '</div>'
      ].join('')

      const btnDropdown = fixtureEl.querySelector('[data-bs-toggle="dropdown"]')
      const dropdown = new Dropdown(btnDropdown)

      btnDropdown.addEventListener('hidden.bs.dropdown', () => {
        throw new Error('should not throw hidden.bs.dropdown event')
      })

      dropdown.hide()

      setTimeout(() => {
        expect().nothing()
        done()
      }, 10)
    })

    it('should not hide a dropdown if hide event is prevented', done => {
      fixtureEl.innerHTML = [
        '<div class="dropdown">',
        '  <button class="btn dropdown-toggle" data-bs-toggle="dropdown">Dropdown</button>',
        '  <div class="dropdown-menu show">',
        '    <a class="dropdown-item" href="#">Secondary link</a>',
        '  </div>',
        '</div>'
      ].join('')

      const btnDropdown = fixtureEl.querySelector('[data-bs-toggle="dropdown"]')
      const dropdownMenu = fixtureEl.querySelector('.dropdown-menu')
      const dropdown = new Dropdown(btnDropdown)

      btnDropdown.addEventListener('hide.bs.dropdown', e => {
        e.preventDefault()
      })

      btnDropdown.addEventListener('hidden.bs.dropdown', () => {
        throw new Error('should not throw hidden.bs.dropdown event')
      })

      dropdown.hide()

      setTimeout(() => {
        expect(dropdownMenu.classList.contains('show')).toEqual(true)
        done()
      })
    })

    it('should remove event listener on touch-enabled device that was added in show method', done => {
      fixtureEl.innerHTML = [
        '<div class="dropdown">',
        '  <button class="btn dropdown-toggle" data-bs-toggle="dropdown">Dropdown</button>',
        '  <div class="dropdown-menu">',
        '    <a class="dropdown-item" href="#">Dropdwon item</a>',
        '  </div>',
        '</div>'
      ].join('')

      const defaultValueOnTouchStart = document.documentElement.ontouchstart
      const btnDropdown = fixtureEl.querySelector('[data-bs-toggle="dropdown"]')
      const dropdown = new Dropdown(btnDropdown)

      document.documentElement.ontouchstart = () => {}
      spyOn(EventHandler, 'off')

      btnDropdown.addEventListener('shown.bs.dropdown', () => {
        dropdown.hide()
      })

      btnDropdown.addEventListener('hidden.bs.dropdown', () => {
        expect(btnDropdown.classList.contains('show')).toEqual(false)
        expect(btnDropdown.getAttribute('aria-expanded')).toEqual('false')
        expect(EventHandler.off).toHaveBeenCalled()

        document.documentElement.ontouchstart = defaultValueOnTouchStart
        done()
      })

      dropdown.show()
    })
  })

  describe('dispose', () => {
    it('should dispose dropdown', () => {
      fixtureEl.innerHTML = [
        '<div class="dropdown">',
        '  <button class="btn dropdown-toggle" data-bs-toggle="dropdown">Dropdown</button>',
        '  <div class="dropdown-menu">',
        '    <a class="dropdown-item" href="#">Secondary link</a>',
        '  </div>',
        '</div>'
      ].join('')

      const btnDropdown = fixtureEl.querySelector('[data-bs-toggle="dropdown"]')

      const dropdown = new Dropdown(btnDropdown)

      expect(dropdown._popper).toBeNull()
      expect(dropdown._menu).not.toBeNull()
      expect(dropdown._element).not.toBeNull()
      spyOn(EventHandler, 'off')

      dropdown.dispose()

      expect(dropdown._menu).toBeNull()
      expect(dropdown._element).toBeNull()
      expect(EventHandler.off).toHaveBeenCalledWith(btnDropdown, Dropdown.EVENT_KEY)
    })

    it('should dispose dropdown with Popper', () => {
      fixtureEl.innerHTML = [
        '<div class="dropdown">',
        '  <button class="btn dropdown-toggle" data-bs-toggle="dropdown">Dropdown</button>',
        '  <div class="dropdown-menu">',
        '    <a class="dropdown-item" href="#">Secondary link</a>',
        '  </div>',
        '</div>'
      ].join('')

      const btnDropdown = fixtureEl.querySelector('[data-bs-toggle="dropdown"]')
      const dropdown = new Dropdown(btnDropdown)

      dropdown.toggle()

      expect(dropdown._popper).not.toBeNull()
      expect(dropdown._menu).not.toBeNull()
      expect(dropdown._element).not.toBeNull()

      dropdown.dispose()

      expect(dropdown._popper).toBeNull()
      expect(dropdown._menu).toBeNull()
      expect(dropdown._element).toBeNull()
    })
  })

  describe('update', () => {
    it('should call Popper and detect navbar on update', () => {
      fixtureEl.innerHTML = [
        '<div class="dropdown">',
        '  <button class="btn dropdown-toggle" data-bs-toggle="dropdown">Dropdown</button>',
        '  <div class="dropdown-menu">',
        '    <a class="dropdown-item" href="#">Secondary link</a>',
        '  </div>',
        '</div>'
      ].join('')

      const btnDropdown = fixtureEl.querySelector('[data-bs-toggle="dropdown"]')
      const dropdown = new Dropdown(btnDropdown)

      dropdown.toggle()

      expect(dropdown._popper).not.toBeNull()

      spyOn(dropdown._popper, 'update')
      spyOn(dropdown, '_detectNavbar')

      dropdown.update()

      expect(dropdown._popper.update).toHaveBeenCalled()
      expect(dropdown._detectNavbar).toHaveBeenCalled()
    })

    it('should just detect navbar on update', () => {
      fixtureEl.innerHTML = [
        '<div class="dropdown">',
        '  <button class="btn dropdown-toggle" data-bs-toggle="dropdown">Dropdown</button>',
        '  <div class="dropdown-menu">',
        '    <a class="dropdown-item" href="#">Secondary link</a>',
        '  </div>',
        '</div>'
      ].join('')

      const btnDropdown = fixtureEl.querySelector('[data-bs-toggle="dropdown"]')
      const dropdown = new Dropdown(btnDropdown)

      spyOn(dropdown, '_detectNavbar')

      dropdown.update()

      expect(dropdown._popper).toBeNull()
      expect(dropdown._detectNavbar).toHaveBeenCalled()
    })
  })

  describe('data-api', () => {
    it('should show and hide a dropdown', done => {
      fixtureEl.innerHTML = [
        '<div class="dropdown">',
        '  <button class="btn dropdown-toggle" data-bs-toggle="dropdown" aria-expanded="false">Dropdown</button>',
        '  <div class="dropdown-menu">',
        '    <a class="dropdown-item" href="#">Secondary link</a>',
        '  </div>',
        '</div>'
      ].join('')

      const btnDropdown = fixtureEl.querySelector('[data-bs-toggle="dropdown"]')
      let showEventTriggered = false
      let hideEventTriggered = false

      btnDropdown.addEventListener('show.bs.dropdown', () => {
        showEventTriggered = true
      })

      btnDropdown.addEventListener('shown.bs.dropdown', e => setTimeout(() => {
        expect(btnDropdown.classList.contains('show')).toEqual(true)
        expect(btnDropdown.getAttribute('aria-expanded')).toEqual('true')
        expect(showEventTriggered).toEqual(true)
        expect(e.relatedTarget).toEqual(btnDropdown)
        document.body.click()
      }))

      btnDropdown.addEventListener('hide.bs.dropdown', () => {
        hideEventTriggered = true
      })

      btnDropdown.addEventListener('hidden.bs.dropdown', e => {
        expect(btnDropdown.classList.contains('show')).toEqual(false)
        expect(btnDropdown.getAttribute('aria-expanded')).toEqual('false')
        expect(hideEventTriggered).toEqual(true)
        expect(e.relatedTarget).toEqual(btnDropdown)
        done()
      })

      btnDropdown.click()
    })

    it('should not use Popper in navbar', done => {
      fixtureEl.innerHTML = [
        '<nav class="navbar navbar-expand-md navbar-light bg-light">',
        '  <div class="dropdown">',
        '    <button class="btn dropdown-toggle" data-bs-toggle="dropdown" aria-expanded="false">Dropdown</button>',
        '    <div class="dropdown-menu">',
        '      <a class="dropdown-item" href="#">Secondary link</a>',
        '    </div>',
        '  </div>',
        '</nav>'
      ].join('')

      const btnDropdown = fixtureEl.querySelector('[data-bs-toggle="dropdown"]')
      const dropdownMenu = fixtureEl.querySelector('.dropdown-menu')
      const dropdown = new Dropdown(btnDropdown)

      btnDropdown.addEventListener('shown.bs.dropdown', () => {
        expect(dropdown._popper).toBeNull()
        expect(dropdownMenu.getAttribute('style')).toEqual(null, 'no inline style applied by Popper')
        done()
      })

      dropdown.show()
    })

    it('should not collapse the dropdown when clicking a select option nested in the dropdown', done => {
      fixtureEl.innerHTML = [
        '<div class="dropdown">',
        '  <button class="btn dropdown-toggle" data-bs-toggle="dropdown" aria-expanded="false">Dropdown</button>',
        '  <div class="dropdown-menu">',
        '    <select>',
        '      <option selected>Open this select menu</option>',
        '      <option value="1">One</option>',
        '    </select>',
        '  </div>',
        '</div>'
      ].join('')

      const btnDropdown = fixtureEl.querySelector('[data-bs-toggle="dropdown"]')
      const dropdownMenu = fixtureEl.querySelector('.dropdown-menu')
      const dropdown = new Dropdown(btnDropdown)

      const hideSpy = spyOn(dropdown, '_completeHide')

      btnDropdown.addEventListener('shown.bs.dropdown', () => {
        const clickEvent = new MouseEvent('click', {
          bubbles: true
        })

        dropdownMenu.querySelector('option').dispatchEvent(clickEvent)
      })

      dropdownMenu.addEventListener('click', event => {
        expect(event.target.tagName).toMatch(/select|option/i)

        Dropdown.clearMenus(event)

        setTimeout(() => {
          expect(hideSpy).not.toHaveBeenCalled()
          done()
        }, 10)
      })

      dropdown.show()
    })

    it('should manage bs attribute `data-bs-popper`="none" when dropdown is in navbar', done => {
      fixtureEl.innerHTML = [
        '<nav class="navbar navbar-expand-md navbar-light bg-light">',
        '  <div class="dropdown">',
        '    <button class="btn dropdown-toggle" data-bs-toggle="dropdown" aria-expanded="false">Dropdown</button>',
        '    <div class="dropdown-menu">',
        '      <a class="dropdown-item" href="#">Secondary link</a>',
        '    </div>',
        '  </div>',
        '</nav>'
      ].join('')

      const btnDropdown = fixtureEl.querySelector('[data-bs-toggle="dropdown"]')
      const dropdownMenu = fixtureEl.querySelector('.dropdown-menu')
      const dropdown = new Dropdown(btnDropdown)

      btnDropdown.addEventListener('shown.bs.dropdown', () => {
        expect(dropdownMenu.getAttribute('data-bs-popper')).toEqual('none')
        dropdown.hide()
      })

      btnDropdown.addEventListener('hidden.bs.dropdown', () => {
        expect(dropdownMenu.getAttribute('data-bs-popper')).toBeNull()
        done()
      })

      dropdown.show()
    })

    it('should not use Popper if display set to static', done => {
      fixtureEl.innerHTML = [
        '<div class="dropdown">',
        '  <button class="btn dropdown-toggle" data-bs-toggle="dropdown" data-bs-display="static">Dropdown</button>',
        '  <div class="dropdown-menu">',
        '    <a class="dropdown-item" href="#">Secondary link</a>',
        '  </div>',
        '</div>'
      ].join('')

      const btnDropdown = fixtureEl.querySelector('[data-bs-toggle="dropdown"]')
      const dropdownMenu = fixtureEl.querySelector('.dropdown-menu')

      btnDropdown.addEventListener('shown.bs.dropdown', () => {
        // Popper adds this attribute when we use it
        expect(dropdownMenu.getAttribute('data-popper-placement')).toEqual(null)
        done()
      })

      btnDropdown.click()
    })

    it('should manage bs attribute `data-bs-popper`="static" when display set to static', done => {
      fixtureEl.innerHTML = [
        '<div class="dropdown">',
        '  <button class="btn dropdown-toggle" data-bs-toggle="dropdown" data-bs-display="static">Dropdown</button>',
        '  <div class="dropdown-menu">',
        '    <a class="dropdown-item" href="#">Secondary link</a>',
        '  </div>',
        '</div>'
      ].join('')

      const btnDropdown = fixtureEl.querySelector('[data-bs-toggle="dropdown"]')
      const dropdownMenu = fixtureEl.querySelector('.dropdown-menu')
      const dropdown = new Dropdown(btnDropdown)

      btnDropdown.addEventListener('shown.bs.dropdown', () => {
        expect(dropdownMenu.getAttribute('data-bs-popper')).toEqual('static')
        dropdown.hide()
      })

      btnDropdown.addEventListener('hidden.bs.dropdown', () => {
        expect(dropdownMenu.getAttribute('data-bs-popper')).toBeNull()
        done()
      })

      dropdown.show()
    })

    it('should remove "show" class if tabbing outside of menu', done => {
      fixtureEl.innerHTML = [
        '<div class="dropdown">',
        '  <button class="btn dropdown-toggle" data-bs-toggle="dropdown">Dropdown</button>',
        '  <div class="dropdown-menu">',
        '    <a class="dropdown-item" href="#">Secondary link</a>',
        '  </div>',
        '</div>'
      ].join('')

      const btnDropdown = fixtureEl.querySelector('[data-bs-toggle="dropdown"]')

      btnDropdown.addEventListener('shown.bs.dropdown', () => {
        expect(btnDropdown.classList.contains('show')).toEqual(true)

        const keyup = createEvent('keyup')

        keyup.key = 'Tab'
        document.dispatchEvent(keyup)
      })

      btnDropdown.addEventListener('hidden.bs.dropdown', () => {
        expect(btnDropdown.classList.contains('show')).toEqual(false)
        done()
      })

      btnDropdown.click()
    })

    it('should remove "show" class if body is clicked, with multiple dropdowns', done => {
      fixtureEl.innerHTML = [
        '<div class="nav">',
        '  <div class="dropdown" id="testmenu">',
        '    <a class="dropdown-toggle" data-bs-toggle="dropdown" href="#testmenu">Test menu</a>',
        '    <div class="dropdown-menu">',
        '      <a class="dropdown-item" href="#sub1">Submenu 1</a>',
        '    </div>',
        '  </div>',
        '</div>',
        '<div class="btn-group">',
        '  <button class="btn">Actions</button>',
        '  <button class="btn dropdown-toggle" data-bs-toggle="dropdown"></button>',
        '  <div class="dropdown-menu">',
        '    <a class="dropdown-item" href="#">Action 1</a>',
        '  </div>',
        '</div>'
      ].join('')

      const triggerDropdownList = fixtureEl.querySelectorAll('[data-bs-toggle="dropdown"]')

      expect(triggerDropdownList.length).toEqual(2)

      const [triggerDropdownFirst, triggerDropdownLast] = triggerDropdownList

      triggerDropdownFirst.addEventListener('shown.bs.dropdown', () => {
        expect(triggerDropdownFirst.classList.contains('show')).toEqual(true)
        expect(fixtureEl.querySelectorAll('.dropdown-menu.show').length).toEqual(1)
        document.body.click()
      })

      triggerDropdownFirst.addEventListener('hidden.bs.dropdown', () => {
        expect(fixtureEl.querySelectorAll('.dropdown-menu.show').length).toEqual(0)
        triggerDropdownLast.click()
      })

      triggerDropdownLast.addEventListener('shown.bs.dropdown', () => {
        expect(triggerDropdownLast.classList.contains('show')).toEqual(true)
        expect(fixtureEl.querySelectorAll('.dropdown-menu.show').length).toEqual(1)
        document.body.click()
      })

      triggerDropdownLast.addEventListener('hidden.bs.dropdown', () => {
        expect(fixtureEl.querySelectorAll('.dropdown-menu.show').length).toEqual(0)
        done()
      })

      triggerDropdownFirst.click()
    })

    it('should remove "show" class if body if tabbing outside of menu, with multiple dropdowns', done => {
      fixtureEl.innerHTML = [
        '<div class="dropdown">',
        '  <a class="dropdown-toggle" data-bs-toggle="dropdown" href="#testmenu">Test menu</a>',
        '  <div class="dropdown-menu">',
        '    <a class="dropdown-item" href="#sub1">Submenu 1</a>',
        '  </div>',
        '</div>',
        '<div class="btn-group">',
        '  <button class="btn">Actions</button>',
        '  <button class="btn dropdown-toggle" data-bs-toggle="dropdown"></button>',
        '  <div class="dropdown-menu">',
        '    <a class="dropdown-item" href="#">Action 1</a>',
        '  </div>',
        '</div>'
      ].join('')

      const triggerDropdownList = fixtureEl.querySelectorAll('[data-bs-toggle="dropdown"]')

      expect(triggerDropdownList.length).toEqual(2)

      const [triggerDropdownFirst, triggerDropdownLast] = triggerDropdownList

      triggerDropdownFirst.addEventListener('shown.bs.dropdown', () => {
        expect(triggerDropdownFirst.classList.contains('show')).toEqual(true, '"show" class added on click')
        expect(fixtureEl.querySelectorAll('.dropdown-menu.show').length).toEqual(1, 'only one dropdown is shown')

        const keyup = createEvent('keyup')
        keyup.key = 'Tab'

        document.dispatchEvent(keyup)
      })

      triggerDropdownFirst.addEventListener('hidden.bs.dropdown', () => {
        expect(fixtureEl.querySelectorAll('.dropdown-menu.show').length).toEqual(0, '"show" class removed')
        triggerDropdownLast.click()
      })

      triggerDropdownLast.addEventListener('shown.bs.dropdown', () => {
        expect(triggerDropdownLast.classList.contains('show')).toEqual(true, '"show" class added on click')
        expect(fixtureEl.querySelectorAll('.dropdown-menu.show').length).toEqual(1, 'only one dropdown is shown')

        const keyup = createEvent('keyup')
        keyup.key = 'Tab'

        document.dispatchEvent(keyup)
      })

      triggerDropdownLast.addEventListener('hidden.bs.dropdown', () => {
        expect(fixtureEl.querySelectorAll('.dropdown-menu.show').length).toEqual(0, '"show" class removed')
        done()
      })

      triggerDropdownFirst.click()
    })

    it('should fire hide and hidden event without a clickEvent if event type is not click', done => {
      fixtureEl.innerHTML = [
        '<div class="dropdown">',
        '  <button class="btn dropdown-toggle" data-bs-toggle="dropdown">Dropdown</button>',
        '  <div class="dropdown-menu">',
        '    <a class="dropdown-item" href="#sub1">Submenu 1</a>',
        '  </div>',
        '</div>'
      ].join('')

      const triggerDropdown = fixtureEl.querySelector('[data-bs-toggle="dropdown"]')

      triggerDropdown.addEventListener('hide.bs.dropdown', e => {
        expect(e.clickEvent).toBeUndefined()
      })

      triggerDropdown.addEventListener('hidden.bs.dropdown', e => {
        expect(e.clickEvent).toBeUndefined()
        done()
      })

      triggerDropdown.addEventListener('shown.bs.dropdown', () => {
        const keydown = createEvent('keydown')

        keydown.key = 'Escape'
        triggerDropdown.dispatchEvent(keydown)
      })

      triggerDropdown.click()
    })

    it('should bubble up the events to the parent elements', done => {
      fixtureEl.innerHTML = [
        '<div class="dropdown">',
        '  <button class="btn dropdown-toggle" data-bs-toggle="dropdown">Dropdown</button>',
        '  <div class="dropdown-menu">',
        '    <a class="dropdown-item" href="#subMenu">Sub menu</a>',
        '  </div>',
        '</div>'
      ].join('')

      const triggerDropdown = fixtureEl.querySelector('[data-bs-toggle="dropdown"]')
      const dropdownParent = fixtureEl.querySelector('.dropdown')
      const dropdown = new Dropdown(triggerDropdown)

      const showFunction = jasmine.createSpy('showFunction')
      dropdownParent.addEventListener('show.bs.dropdown', showFunction)

      const shownFunction = jasmine.createSpy('shownFunction')
      dropdownParent.addEventListener('shown.bs.dropdown', () => {
        shownFunction()
        dropdown.hide()
      })

      const hideFunction = jasmine.createSpy('hideFunction')
      dropdownParent.addEventListener('hide.bs.dropdown', hideFunction)

      dropdownParent.addEventListener('hidden.bs.dropdown', () => {
        expect(showFunction).toHaveBeenCalled()
        expect(shownFunction).toHaveBeenCalled()
        expect(hideFunction).toHaveBeenCalled()
        done()
      })

      dropdown.show()
    })

    it('should ignore keyboard events within <input>s and <textarea>s', done => {
      fixtureEl.innerHTML = [
        '<div class="dropdown">',
        '  <button class="btn dropdown-toggle" data-bs-toggle="dropdown">Dropdown</button>',
        '  <div class="dropdown-menu">',
        '    <a class="dropdown-item" href="#sub1">Submenu 1</a>',
        '    <input type="text">',
        '    <textarea></textarea>',
        '  </div>',
        '</div>'
      ].join('')

      const triggerDropdown = fixtureEl.querySelector('[data-bs-toggle="dropdown"]')
      const input = fixtureEl.querySelector('input')
      const textarea = fixtureEl.querySelector('textarea')

      triggerDropdown.addEventListener('shown.bs.dropdown', () => {
        input.focus()
        const keydown = createEvent('keydown')

        keydown.key = 'ArrowUp'
        input.dispatchEvent(keydown)

        expect(document.activeElement).toEqual(input, 'input still focused')

        textarea.focus()
        textarea.dispatchEvent(keydown)

        expect(document.activeElement).toEqual(textarea, 'textarea still focused')
        done()
      })

      triggerDropdown.click()
    })

    it('should skip disabled element when using keyboard navigation', done => {
      fixtureEl.innerHTML = [
        '<div class="dropdown">',
        '  <button class="btn dropdown-toggle" data-bs-toggle="dropdown">Dropdown</button>',
        '  <div class="dropdown-menu">',
        '    <a class="dropdown-item disabled" href="#sub1">Submenu 1</a>',
        '    <button class="dropdown-item" type="button" disabled>Disabled button</button>',
        '    <a id="item1" class="dropdown-item" href="#">Another link</a>',
        '  </div>',
        '</div>'
      ].join('')

      const triggerDropdown = fixtureEl.querySelector('[data-bs-toggle="dropdown"]')

      triggerDropdown.addEventListener('shown.bs.dropdown', () => {
        const keydown = createEvent('keydown')
        keydown.key = 'ArrowDown'

        triggerDropdown.dispatchEvent(keydown)
        triggerDropdown.dispatchEvent(keydown)

        expect(document.activeElement.classList.contains('disabled')).toEqual(false, '.disabled not focused')
        expect(document.activeElement.hasAttribute('disabled')).toEqual(false, ':disabled not focused')
        done()
      })

      triggerDropdown.click()
    })

    it('should skip hidden element when using keyboard navigation', done => {
      fixtureEl.innerHTML = [
        '<style>',
        '  .d-none {',
        '    display: none;',
        '  }',
        '</style>',
        '<div class="dropdown">',
        '  <button class="btn dropdown-toggle" data-bs-toggle="dropdown">Dropdown</button>',
        '  <div class="dropdown-menu">',
        '    <button class="dropdown-item d-none" type="button">Hidden button by class</button>',
        '    <a class="dropdown-item" href="#sub1" style="display: none">Hidden link</a>',
        '    <a class="dropdown-item" href="#sub1" style="visibility: hidden">Hidden link</a>',
        '    <a id="item1" class="dropdown-item" href="#">Another link</a>',
        '  </div>',
        '</div>'
      ].join('')

      const triggerDropdown = fixtureEl.querySelector('[data-bs-toggle="dropdown"]')

      triggerDropdown.addEventListener('shown.bs.dropdown', () => {
        const keydown = createEvent('keydown')
        keydown.key = 'ArrowDown'

        triggerDropdown.dispatchEvent(keydown)

        expect(document.activeElement.classList.contains('d-none')).toEqual(false, '.d-none not focused')
        expect(document.activeElement.style.display).not.toBe('none', '"display: none" not focused')
        expect(document.activeElement.style.visibility).not.toBe('hidden', '"visibility: hidden" not focused')

        done()
      })

      triggerDropdown.click()
    })

    it('should focus next/previous element when using keyboard navigation', done => {
      fixtureEl.innerHTML = [
        '<div class="dropdown">',
        '  <button class="btn dropdown-toggle" data-bs-toggle="dropdown">Dropdown</button>',
        '  <div class="dropdown-menu">',
        '    <a id="item1" class="dropdown-item" href="#">A link</a>',
        '    <a id="item2" class="dropdown-item" href="#">Another link</a>',
        '  </div>',
        '</div>'
      ].join('')

      const triggerDropdown = fixtureEl.querySelector('[data-bs-toggle="dropdown"]')
      const item1 = fixtureEl.querySelector('#item1')
      const item2 = fixtureEl.querySelector('#item2')

      triggerDropdown.addEventListener('shown.bs.dropdown', () => {
        const keydownArrowDown = createEvent('keydown')
        keydownArrowDown.key = 'ArrowDown'

        triggerDropdown.dispatchEvent(keydownArrowDown)
        expect(document.activeElement).toEqual(item1, 'item1 is focused')

        document.activeElement.dispatchEvent(keydownArrowDown)
        expect(document.activeElement).toEqual(item2, 'item2 is focused')

        const keydownArrowUp = createEvent('keydown')
        keydownArrowUp.key = 'ArrowUp'

        document.activeElement.dispatchEvent(keydownArrowUp)
        expect(document.activeElement).toEqual(item1, 'item1 is focused')

        done()
      })

      triggerDropdown.click()
    })

    it('should open the dropdown and focus on the last item when using ArrowUp for the first time', done => {
      fixtureEl.innerHTML = [
        '<div class="dropdown">',
        '  <button class="btn dropdown-toggle" data-bs-toggle="dropdown">Dropdown</button>',
        '  <div class="dropdown-menu">',
        '    <a id="item1" class="dropdown-item" href="#">A link</a>',
        '    <a id="item2" class="dropdown-item" href="#">Another link</a>',
        '  </div>',
        '</div>'
      ].join('')

      const triggerDropdown = fixtureEl.querySelector('[data-bs-toggle="dropdown"]')
      const lastItem = fixtureEl.querySelector('#item2')

      triggerDropdown.addEventListener('shown.bs.dropdown', () => {
        setTimeout(() => {
          expect(document.activeElement).toEqual(lastItem, 'item2 is focused')
          done()
        })
      })

      const keydown = createEvent('keydown')
      keydown.key = 'ArrowUp'
      triggerDropdown.dispatchEvent(keydown)
    })

    it('should open the dropdown and focus on the first item when using ArrowDown for the first time', done => {
      fixtureEl.innerHTML = [
        '<div class="dropdown">',
        '  <button class="btn dropdown-toggle" data-bs-toggle="dropdown">Dropdown</button>',
        '  <div class="dropdown-menu">',
        '    <a id="item1" class="dropdown-item" href="#">A link</a>',
        '    <a id="item2" class="dropdown-item" href="#">Another link</a>',
        '  </div>',
        '</div>'
      ].join('')

      const triggerDropdown = fixtureEl.querySelector('[data-bs-toggle="dropdown"]')
      const firstItem = fixtureEl.querySelector('#item1')

      triggerDropdown.addEventListener('shown.bs.dropdown', () => {
        setTimeout(() => {
          expect(document.activeElement).toEqual(firstItem, 'item1 is focused')
          done()
        })
      })

      const keydown = createEvent('keydown')
      keydown.key = 'ArrowDown'
      triggerDropdown.dispatchEvent(keydown)
    })

    it('should not close the dropdown if the user clicks on a text field within dropdown-menu', done => {
      fixtureEl.innerHTML = [
        '<div class="dropdown">',
        '  <button class="btn dropdown-toggle" data-bs-toggle="dropdown">Dropdown</button>',
        '  <div class="dropdown-menu">',
        '    <input type="text">',
        '  </div>',
        '</div>'
      ].join('')

      const triggerDropdown = fixtureEl.querySelector('[data-bs-toggle="dropdown"]')
      const input = fixtureEl.querySelector('input')

      input.addEventListener('click', () => {
        expect(triggerDropdown.classList.contains('show')).toEqual(true, 'dropdown menu is shown')
        done()
      })

      triggerDropdown.addEventListener('shown.bs.dropdown', () => {
        expect(triggerDropdown.classList.contains('show')).toEqual(true, 'dropdown menu is shown')
        input.dispatchEvent(createEvent('click'))
      })

      triggerDropdown.click()
    })

    it('should not close the dropdown if the user clicks on a textarea within dropdown-menu', done => {
      fixtureEl.innerHTML = [
        '<div class="dropdown">',
        '  <button class="btn dropdown-toggle" data-bs-toggle="dropdown">Dropdown</button>',
        '  <div class="dropdown-menu">',
        '    <textarea></textarea>',
        '  </div>',
        '</div>'
      ].join('')

      const triggerDropdown = fixtureEl.querySelector('[data-bs-toggle="dropdown"]')
      const textarea = fixtureEl.querySelector('textarea')

      textarea.addEventListener('click', () => {
        expect(triggerDropdown.classList.contains('show')).toEqual(true, 'dropdown menu is shown')
        done()
      })

      triggerDropdown.addEventListener('shown.bs.dropdown', () => {
        expect(triggerDropdown.classList.contains('show')).toEqual(true, 'dropdown menu is shown')
        textarea.dispatchEvent(createEvent('click'))
      })

      triggerDropdown.click()
    })

    it('should close the dropdown if the user clicks on a text field that is not contained within dropdown-menu', done => {
      fixtureEl.innerHTML = [
        '<div class="dropdown">',
        '  <button class="btn dropdown-toggle" data-bs-toggle="dropdown">Dropdown</button>',
        '  <div class="dropdown-menu">',
        '  </div>',
        '</div>',
        '<input type="text">'
      ]

      const triggerDropdown = fixtureEl.querySelector('[data-bs-toggle="dropdown"]')
      const input = fixtureEl.querySelector('input')

      triggerDropdown.addEventListener('hidden.bs.dropdown', () => {
        expect().nothing()
        done()
      })

      triggerDropdown.addEventListener('shown.bs.dropdown', () => {
        input.dispatchEvent(createEvent('click', {
          bubbles: true
        }))
      })

      triggerDropdown.click()
    })

    it('should ignore keyboard events for <input>s and <textarea>s within dropdown-menu, except for escape key', done => {
      fixtureEl.innerHTML = [
        '<div class="dropdown">',
        '  <button class="btn dropdown-toggle" data-bs-toggle="dropdown">Dropdown</button>',
        '  <div class="dropdown-menu">',
        '    <a class="dropdown-item" href="#sub1">Submenu 1</a>',
        '    <input type="text">',
        '    <textarea></textarea>',
        '  </div>',
        '</div>'
      ].join('')

      const triggerDropdown = fixtureEl.querySelector('[data-bs-toggle="dropdown"]')
      const input = fixtureEl.querySelector('input')
      const textarea = fixtureEl.querySelector('textarea')

      const keydownSpace = createEvent('keydown')
      keydownSpace.key = 'Space'

      const keydownArrowUp = createEvent('keydown')
      keydownArrowUp.key = 'ArrowUp'

      const keydownArrowDown = createEvent('keydown')
      keydownArrowDown.key = 'ArrowDown'

      const keydownEscape = createEvent('keydown')
      keydownEscape.key = 'Escape'

      triggerDropdown.addEventListener('shown.bs.dropdown', () => {
        // Key Space
        input.focus()
        input.dispatchEvent(keydownSpace)

        expect(document.activeElement).toEqual(input, 'input still focused')

        textarea.focus()
        textarea.dispatchEvent(keydownSpace)

        expect(document.activeElement).toEqual(textarea, 'textarea still focused')

        // Key ArrowUp
        input.focus()
        input.dispatchEvent(keydownArrowUp)

        expect(document.activeElement).toEqual(input, 'input still focused')

        textarea.focus()
        textarea.dispatchEvent(keydownArrowUp)

        expect(document.activeElement).toEqual(textarea, 'textarea still focused')

        // Key ArrowDown
        input.focus()
        input.dispatchEvent(keydownArrowDown)

        expect(document.activeElement).toEqual(input, 'input still focused')

        textarea.focus()
        textarea.dispatchEvent(keydownArrowDown)

        expect(document.activeElement).toEqual(textarea, 'textarea still focused')

        // Key Escape
        input.focus()
        input.dispatchEvent(keydownEscape)

        expect(triggerDropdown.classList.contains('show')).toEqual(false, 'dropdown menu is not shown')
        done()
      })

      triggerDropdown.click()
    })

    it('should not open dropdown if escape key was pressed on the toggle', done => {
      fixtureEl.innerHTML = [
        '<div class="tabs">',
        '  <div class="dropdown">',
        '    <button disabled class="btn dropdown-toggle" data-bs-toggle="dropdown">Dropdown</button>',
        '    <div class="dropdown-menu">',
        '      <a class="dropdown-item" href="#">Secondary link</a>',
        '      <a class="dropdown-item" href="#">Something else here</a>',
        '      <div class="divider"></div>',
        '     <a class="dropdown-item" href="#">Another link</a>',
        '   </div>',
        '  </div>',
        '</div>'
      ]

      const triggerDropdown = fixtureEl.querySelector('[data-bs-toggle="dropdown"]')
      const dropdown = new Dropdown(triggerDropdown)
      const button = fixtureEl.querySelector('button[data-bs-toggle="dropdown"]')

      spyOn(dropdown, 'toggle')

      // Key escape
      button.focus()
      // Key escape
      const keydownEscape = createEvent('keydown')
      keydownEscape.key = 'Escape'
      button.dispatchEvent(keydownEscape)

      setTimeout(() => {
        expect(dropdown.toggle).not.toHaveBeenCalled()
        expect(triggerDropdown.classList.contains('show')).toEqual(false)
        done()
      }, 20)
    })

    it('should propagate escape key events if dropdown is closed', done => {
      fixtureEl.innerHTML = [
        '<div class="parent">',
        '  <div class="dropdown">',
        '    <button class="btn dropdown-toggle" data-bs-toggle="dropdown">Dropdown</button>',
        '    <div class="dropdown-menu">',
        '      <a class="dropdown-item" href="#">Some Item</a>',
        '   </div>',
        '  </div>',
        '</div>'
      ]

      const parent = fixtureEl.querySelector('.parent')
      const toggle = fixtureEl.querySelector('[data-bs-toggle="dropdown"]')

      const parentKeyHandler = jasmine.createSpy('parentKeyHandler')

      parent.addEventListener('keydown', parentKeyHandler)
      parent.addEventListener('keyup', () => {
        expect(parentKeyHandler).toHaveBeenCalled()
        done()
      })

      const keydownEscape = createEvent('keydown', { bubbles: true })
      keydownEscape.key = 'Escape'
      const keyupEscape = createEvent('keyup', { bubbles: true })
      keyupEscape.key = 'Escape'

      toggle.focus()
      toggle.dispatchEvent(keydownEscape)
      toggle.dispatchEvent(keyupEscape)
    })

    it('should close dropdown (only) by clicking inside the dropdown menu when it has data-attribute `data-bs-auto-close="inside"`', done => {
      fixtureEl.innerHTML = [
        '<div class="dropdown">',
        '  <button class="btn dropdown-toggle" data-bs-toggle="dropdown" data-bs-auto-close="inside">Dropdown toggle</button>',
        '  <div class="dropdown-menu">',
        '    <a class="dropdown-item" href="#">Dropdown item</a>',
        ' </div>',
        '</div>'
      ]

      const dropdownToggle = fixtureEl.querySelector('[data-bs-toggle="dropdown"]')
      const dropdownMenu = fixtureEl.querySelector('.dropdown-menu')

      const expectDropdownToBeOpened = () => setTimeout(() => {
        expect(dropdownToggle.classList.contains('show')).toEqual(true)
        dropdownMenu.click()
      }, 150)

      dropdownToggle.addEventListener('shown.bs.dropdown', () => {
        document.documentElement.click()
        expectDropdownToBeOpened()
      })

      dropdownToggle.addEventListener('hidden.bs.dropdown', () => setTimeout(() => {
        expect(dropdownToggle.classList.contains('show')).toEqual(false)
        done()
      }))

      dropdownToggle.click()
    })

    it('should close dropdown (only) by clicking outside the dropdown menu when it has data-attribute `data-bs-auto-close="outside"`', done => {
      fixtureEl.innerHTML = [
        '<div class="dropdown">',
        '  <button class="btn dropdown-toggle" data-bs-toggle="dropdown" data-bs-auto-close="outside">Dropdown toggle</button>',
        '  <div class="dropdown-menu">',
        '    <a class="dropdown-item" href="#">Dropdown item</a>',
        ' </div>',
        '</div>'
      ]

      const dropdownToggle = fixtureEl.querySelector('[data-bs-toggle="dropdown"]')
      const dropdownMenu = fixtureEl.querySelector('.dropdown-menu')

      const expectDropdownToBeOpened = () => setTimeout(() => {
        expect(dropdownToggle.classList.contains('show')).toEqual(true)
        document.documentElement.click()
      }, 150)

      dropdownToggle.addEventListener('shown.bs.dropdown', () => {
        dropdownMenu.click()
        expectDropdownToBeOpened()
      })

      dropdownToggle.addEventListener('hidden.bs.dropdown', () => {
        expect(dropdownToggle.classList.contains('show')).toEqual(false)
        done()
      })

      dropdownToggle.click()
    })

    it('should not close dropdown by clicking inside or outside the dropdown menu when it has data-attribute `data-bs-auto-close="false"`', done => {
      fixtureEl.innerHTML = [
        '<div class="dropdown">',
        '  <button class="btn dropdown-toggle" data-bs-toggle="dropdown" data-bs-auto-close="false">Dropdown toggle</button>',
        '  <div class="dropdown-menu">',
        '    <a class="dropdown-item" href="#">Dropdown item</a>',
        ' </div>',
        '</div>'
      ]

      const dropdownToggle = fixtureEl.querySelector('[data-bs-toggle="dropdown"]')
      const dropdownMenu = fixtureEl.querySelector('.dropdown-menu')

      const expectDropdownToBeOpened = (shouldTriggerClick = true) => setTimeout(() => {
        expect(dropdownToggle.classList.contains('show')).toEqual(true)
        if (shouldTriggerClick) {
          document.documentElement.click()
        } else {
          done()
        }

        expectDropdownToBeOpened(false)
      }, 150)

      dropdownToggle.addEventListener('shown.bs.dropdown', () => {
        dropdownMenu.click()
        expectDropdownToBeOpened()
      })

      dropdownToggle.click()
    })
  })

  describe('jQueryInterface', () => {
    it('should create a dropdown', () => {
      fixtureEl.innerHTML = '<div></div>'

      const div = fixtureEl.querySelector('div')

      jQueryMock.fn.dropdown = Dropdown.jQueryInterface
      jQueryMock.elements = [div]

      jQueryMock.fn.dropdown.call(jQueryMock)

      expect(Dropdown.getInstance(div)).not.toBeNull()
    })

    it('should not re create a dropdown', () => {
      fixtureEl.innerHTML = '<div></div>'

      const div = fixtureEl.querySelector('div')
      const dropdown = new Dropdown(div)

      jQueryMock.fn.dropdown = Dropdown.jQueryInterface
      jQueryMock.elements = [div]

      jQueryMock.fn.dropdown.call(jQueryMock)

      expect(Dropdown.getInstance(div)).toEqual(dropdown)
    })

    it('should throw error on undefined method', () => {
      fixtureEl.innerHTML = '<div></div>'

      const div = fixtureEl.querySelector('div')
      const action = 'undefinedMethod'

      jQueryMock.fn.dropdown = Dropdown.jQueryInterface
      jQueryMock.elements = [div]

      expect(() => {
        jQueryMock.fn.dropdown.call(jQueryMock, action)
      }).toThrowError(TypeError, `No method named "${action}"`)
    })
  })

  describe('getInstance', () => {
    it('should return dropdown instance', () => {
      fixtureEl.innerHTML = '<div></div>'

      const div = fixtureEl.querySelector('div')
      const dropdown = new Dropdown(div)

      expect(Dropdown.getInstance(div)).toEqual(dropdown)
      expect(Dropdown.getInstance(div)).toBeInstanceOf(Dropdown)
    })

    it('should return null when there is no dropdown instance', () => {
      fixtureEl.innerHTML = '<div></div>'

      const div = fixtureEl.querySelector('div')

      expect(Dropdown.getInstance(div)).toEqual(null)
    })
  })

  describe('getOrCreateInstance', () => {
    it('should return dropdown instance', () => {
      fixtureEl.innerHTML = '<div></div>'

      const div = fixtureEl.querySelector('div')
      const dropdown = new Dropdown(div)

      expect(Dropdown.getOrCreateInstance(div)).toEqual(dropdown)
      expect(Dropdown.getInstance(div)).toEqual(Dropdown.getOrCreateInstance(div, {}))
      expect(Dropdown.getOrCreateInstance(div)).toBeInstanceOf(Dropdown)
    })

    it('should return new instance when there is no dropdown instance', () => {
      fixtureEl.innerHTML = '<div></div>'

      const div = fixtureEl.querySelector('div')

      expect(Dropdown.getInstance(div)).toEqual(null)
      expect(Dropdown.getOrCreateInstance(div)).toBeInstanceOf(Dropdown)
    })

    it('should return new instance when there is no dropdown instance with given configuration', () => {
      fixtureEl.innerHTML = '<div></div>'

      const div = fixtureEl.querySelector('div')

      expect(Dropdown.getInstance(div)).toEqual(null)
      const dropdown = Dropdown.getOrCreateInstance(div, {
        display: 'dynamic'
      })
      expect(dropdown).toBeInstanceOf(Dropdown)

      expect(dropdown._config.display).toEqual('dynamic')
    })

    it('should return the instance when exists without given configuration', () => {
      fixtureEl.innerHTML = '<div></div>'

      const div = fixtureEl.querySelector('div')
      const dropdown = new Dropdown(div, {
        display: 'dynamic'
      })
      expect(Dropdown.getInstance(div)).toEqual(dropdown)

      const dropdown2 = Dropdown.getOrCreateInstance(div, {
        display: 'static'
      })
      expect(dropdown).toBeInstanceOf(Dropdown)
      expect(dropdown2).toEqual(dropdown)

      expect(dropdown2._config.display).toEqual('dynamic')
    })
  })

  it('should open dropdown when pressing keydown or keyup', done => {
    fixtureEl.innerHTML = [
      '<div class="dropdown">',
      '  <button class="btn dropdown-toggle" data-bs-toggle="dropdown">Dropdown</button>',
      '  <div class="dropdown-menu">',
      '    <a class="dropdown-item disabled" href="#sub1">Submenu 1</a>',
      '    <button class="dropdown-item" type="button" disabled>Disabled button</button>',
      '    <a id="item1" class="dropdown-item" href="#">Another link</a>',
      '  </div>',
      '</div>'
    ].join('')

    const triggerDropdown = fixtureEl.querySelector('[data-bs-toggle="dropdown"]')
    const dropdown = fixtureEl.querySelector('.dropdown')

    const keydown = createEvent('keydown')
    keydown.key = 'ArrowDown'

    const keyup = createEvent('keyup')
    keyup.key = 'ArrowUp'

    const handleArrowDown = () => {
      expect(triggerDropdown.classList.contains('show')).toEqual(true)
      expect(triggerDropdown.getAttribute('aria-expanded')).toEqual('true')
      setTimeout(() => {
        dropdown.hide()
        keydown.key = 'ArrowUp'
        triggerDropdown.dispatchEvent(keyup)
      }, 20)
    }

    const handleArrowUp = () => {
      expect(triggerDropdown.classList.contains('show')).toEqual(true)
      expect(triggerDropdown.getAttribute('aria-expanded')).toEqual('true')
      done()
    }

    dropdown.addEventListener('shown.bs.dropdown', event => {
      if (event.target.key === 'ArrowDown') {
        handleArrowDown()
      } else {
        handleArrowUp()
      }
    })

    triggerDropdown.dispatchEvent(keydown)
  })

  it('should allow `data-bs-toggle="dropdown"` click events to bubble up', () => {
    fixtureEl.innerHTML = [
      '<div class="dropdown">',
      '  <button class="btn dropdown-toggle" data-bs-toggle="dropdown">Dropdown</button>',
      '  <div class="dropdown-menu">',
      '    <a class="dropdown-item" href="#">Secondary link</a>',
      '  </div>',
      '</div>'
    ].join('')

    const btnDropdown = fixtureEl.querySelector('[data-bs-toggle="dropdown"]')
    const clickListener = jasmine.createSpy('clickListener')
    const delegatedClickListener = jasmine.createSpy('delegatedClickListener')

    btnDropdown.addEventListener('click', clickListener)
    document.addEventListener('click', delegatedClickListener)

    btnDropdown.click()

    expect(clickListener).toHaveBeenCalled()
    expect(delegatedClickListener).toHaveBeenCalled()
  })

  it('should open the dropdown when clicking the child element inside `data-bs-toggle="dropdown"`', done => {
    fixtureEl.innerHTML = [
      '<div class="container">',
      '  <div class="dropdown">',
      '    <button class="btn dropdown-toggle" data-bs-toggle="dropdown"><span id="childElement">Dropdown</span></button>',
      '    <div class="dropdown-menu">',
      '      <a class="dropdown-item" href="#subMenu">Sub menu</a>',
      '    </div>',
      '  </div>',
      '</div>'
    ].join('')

    const btnDropdown = fixtureEl.querySelector('[data-bs-toggle="dropdown"]')
    const childElement = fixtureEl.querySelector('#childElement')

    btnDropdown.addEventListener('shown.bs.dropdown', () => setTimeout(() => {
      expect(btnDropdown.classList.contains('show')).toEqual(true)
      expect(btnDropdown.getAttribute('aria-expanded')).toEqual('true')
      done()
    }))

    childElement.click()
  })
})