reblend-testing-library/lib/__tests__/stopwatch.js

Simple and complete Reblendjs testing utilities that encourage good testing practices.

"use strict";

var _reblendjs = require("reblendjs");
var _ = require("../");
class StopWatch extends _reblendjs.Reblend {
  initState() {
    this.state = {
      lapse: 0,
      running: false
    };
  }
  handleRunClick() {
    this.setState(state => {
      if (state.running) {
        clearInterval(this.timer);
      } else {
        const startTime = Date.now() - this.state.lapse;
        this.timer = setInterval(() => {
          this.setState({
            lapse: Date.now() - startTime
          });
        });
      }
      return {
        running: !state.running
      };
    });
  }
  handleClearClick() {
    clearInterval(this.timer);
    this.setState({
      lapse: 0,
      running: false
    });
  }
  componentWillUnmount() {
    clearInterval(this.timer);
  }
  html() {
    const {
      lapse,
      running
    } = this.state;
    return _reblendjs.Reblend.construct.bind(this)("div", null, _reblendjs.Reblend.construct.bind(this)("span", null, lapse, "ms"), _reblendjs.Reblend.construct.bind(this)("button", {
      onClick: this.handleRunClick
    }, running ? "Stop" : "Start"), _reblendjs.Reblend.construct.bind(this)("button", {
      onClick: this.handleClearClick
    }, "Clear"));
  }
}
const sleep = t => new Promise(resolve => setTimeout(resolve, t));
test("unmounts a component", async () => {
  const {
    unmount,
    container,
    debug
  } = await (0, _.render)(_reblendjs.Reblend.construct.bind(this)(StopWatch, null));
  //debug(container);
  _.fireEvent.click(_.screen.getByText("Start"));
  await unmount();
  // hey there reader! You don't need to have an assertion like this one
  // this is just me making sure that the unmount function works.
  // You don't need to do this in your apps. Just rely on the fact that this works.
  expect(container).toBeEmptyDOMElement();
  // just wait to see if the interval is cleared or not
  // if it's not, then we'll call setState on an unmounted component
  // and get an error.
  await sleep(5);
});