element-plus/packages/components/backtop/__tests__/backtop.test.tsx

import { nextTick } from 'vue'
import { mount } from '@vue/test-utils'
import { describe, expect, test } from 'vitest'
import { CaretTop } from '@element-plus/icons-vue'
import Backtop from '../src/backtop.vue'
import type { VNode } from 'vue'

const _mount = (render: () => VNode) =>
  mount(render, { attachTo: document.body })

describe('Backtop.vue', () => {
  test('render', async () => {
    const wrapper = _mount(() => (
      <div class="target" style="height: 100px; overflow: auto">
        <div style="height: 10000px; width: 100%">
          <Backtop
            target=".target"
            visibilityHeight={2000}
            right={100}
            bottom={200}
          />
        </div>
      </div>
    ))
    await nextTick()

    expect(wrapper.find('.el-backtop').exists()).toBe(false)
    wrapper.element.scrollTop = 2000
    await wrapper.trigger('scroll')
    expect(wrapper.find('.el-backtop').exists()).toBe(true)

    expect(wrapper.find('.el-backtop').attributes('style')).toBe(
      'right: 100px; bottom: 200px;'
    )
    expect(wrapper.findComponent(CaretTop).exists()).toBe(true)

    await wrapper.trigger('click')
    expect(wrapper.emitted()).toBeDefined()
  })
})