reactjs - 使用 @testing-library/react 测试 Material ui slider

Question

您好，我正在尝试测试一个使用 Material-UI 创建的 Slider 组件，但我无法将测试转到 pass。 .我想使用 fireEvent 测试值的变化。与 @testing-library/react .我一直在关注这篇文章以正确查询 DOM，但我无法获得正确的 DOM 节点。
提前致谢。
<Slider />组件

// @format
// @flow

import * as React from "react";
import styled from "styled-components";
import { Slider as MaterialUISlider } from "@material-ui/core";
import { withStyles, makeStyles } from "@material-ui/core/styles";
import { priceRange } from "../../../domain/Search/PriceRange/priceRange";

const Wrapper = styled.div`
  width: 93%;
  display: inline-block;
  margin-left: 0.5em;
  margin-right: 0.5em;
  margin-bottom: 0.5em;
`;

// ommited code pertaining props and styles for simplicity

function Slider(props: SliderProps) {
  const initialState = [1, 100];
  const [value, setValue] = React.useState(initialState);

  function onHandleChangeCommitted(e, latestValue) {
    e.preventDefault();
    const { onUpdate } = props;
    const newPriceRange = priceRange(latestValue);
    onUpdate(newPriceRange);
  }

  function onHandleChange(e, newValue) {
    e.preventDefault();
    setValue(newValue);
  }

  return (
    <Wrapper
      aria-label="range-slider"
    >
      <SliderWithStyles
        aria-labelledby="range-slider"
        defaultValue={initialState}
        // getAriaLabel={index =>
        //   index === 0 ? "Minimum Price" : "Maximum Price"
        // }
        getAriaValueText={valueText}
        onChange={onHandleChange}
        onChangeCommitted={onHandleChangeCommitted}
        valueLabelDisplay="auto"
        value={value}
      />
    </Wrapper>
  );
}

export default Slider;

Slider.test.js

// @flow

import React from "react";
import { cleanup,
  render,
  getAllByAltText,
  fireEvent,
  waitForElement } from "@testing-library/react";
import "@testing-library/jest-dom/extend-expect";

import Slider from "../Slider";


afterEach(cleanup);

describe("<Slider /> specs", () => {

  // [NOTE]: Works, but maybe a better way to do it ?
  xdescribe("<Slider /> component aria-label", () => {

    it("renders without crashing", () => {
      const { container } = render(<Slider />);
      expect(container.firstChild).toBeInTheDocument(); 
    });
  });

  // [ASK]: How to test the event handlers with fireEvent.
  describe("<Slider /> props", () => {

    it("display a initial min value of '1'", () => {
      const renderResult = render(<Slider />);
      // TODO
    });

    it("display a initial max value of '100'", () => {
      const renderResult = render(<Slider />);
      // TODO
    });

    xit("display to values via the onHandleChangeCommitted event when dragging stop", () => {
      const renderResult = render(<Slider />);
      console.log(renderResult)
      // fireEvent.change(renderResult.getByText("1"))
      // expect(onChange).toHaveBeenCalled(0);
    });

    // [NOTE]: Does not work, returns undefined
    xit("display to values via the onHandleChange event when dragging stop", () => {
      const renderResult = render(<Slider />);

      console.log(renderResult.container);
      
      const spanNodeWithAriaAttribute = renderResult.container.firstChild.getElementsByTagName("span")[0].getAttribute('aria-label')
      expect(spanNodeWithAriaAttribute).toBe(/range-slider/)
    });
  });

  // [ASK]: Works, but a snapshot is an overkill a better way of doing this ?
  xdescribe("<Slider /> snapshot", () => {

    it("renders without crashing", () => {
      const { container } = render(<Slider />);
      expect(container.firstChild).toMatchSnapshot();
    });
  });
});

Answer 1

经过几个小时的斗争后，我能够解决与测试 MUI slider 相关的案例

这真的取决于你需要如何测试你的，在我的情况下，我必须检查标签文本内容是否在使用 marks 单击标记后发生变化 slider Prop 。

问题

1) slider组件根据元素 getBoundingClientRect 计算返回值和 MouseEvent
2) 如何查询slider并触发事件。

3)JSDOM对读取元素实际高度和宽度的限制导致问题1

解决方案

1) 模拟getBoundingClientRect也应该解决问题3

2) 将测试 ID 添加到 slider 并使用使用 fireEvent.mouseDown(contaner, {....})

const sliderLabel = screen.getByText("Default text that the user should see")

// add data-testid to slider
const sliderInput = screen.getByTestId("slider")

// mock the getBoundingClientRect
    sliderInput.getBoundingClientRect = jest.fn(() => {
      return {
        bottom: 286.22918701171875,
        height: 28,
        left: 19.572917938232422,
        right: 583.0937919616699,
        top: 258.22918701171875,
        width: 563.5208740234375,
        x: 19.572917938232422,
        y: 258.22918701171875,
      }
    })

    expect(sliderInput).toBeInTheDocument()

    expect(sliderLabel).toHaveTextContent("Default text that the user should see")
    await fireEvent.mouseDown(sliderInput, { clientX: 162, clientY: 302 })
    expect(sliderLabel).toHaveTextContent(
      "New text that the user should see"
    )