@nateradebaugh/react-datetime/src/test/viewDate.test.js

A lightweight but complete datetime picker React.js component

import utils from "./testUtils";
import Enzyme from "enzyme";
import Adapter from "enzyme-adapter-react-16";
import { advanceTo as mockDateTo } from "jest-date-mock";
import format from "date-fns/format";

Enzyme.configure({ adapter: new Adapter() });

// Mock date to get rid of time as a factor to make tests deterministic
mockDateTo("September 2, 2018 03:24:00");

describe("with viewDate", () => {
  it("date value", () => {
    const date = new Date(2000, 0, 15, 2, 2, 2, 2),
      strDate = format(date, "MMMM YYYY"),
      component = utils.createDatetime({ viewDate: date });
    expect(utils.getViewDateValue(component)).toEqual(strDate);
  });

  it("Date value", () => {
    const date = new Date(2000, 0, 15, 2, 2, 2, 2),
      strDate = format(date, "MMMM YYYY"),
      component = utils.createDatetime({ viewDate: date });
    expect(utils.getViewDateValue(component)).toEqual(strDate);
  });

  it("string value", () => {
    const date = new Date(2000, 0, 15, 2, 2, 2, 2),
      strDate = `${format(date, "MM/DD/YYYY")} ${format(date, "h:mm A")}`,
      expectedStrDate = format(date, "MMMM YYYY"),
      component = utils.createDatetime({ viewDate: strDate });
    expect(utils.getViewDateValue(component)).toEqual(expectedStrDate);
  });

  it("UTC value from UTC string", () => {
    const date = new Date(2000, 0, 15, 2, 2, 2, 2),
      dateUTC = new Date(date.getTime()),
      strDateUTC = `${format(dateUTC, "MM/DD/YYYY")} ${format(
        dateUTC,
        "h:mm A"
      )}`,
      expectedStrDate = format(dateUTC, "MMMM YYYY"),
      component = utils.createDatetime({ viewDate: strDateUTC, utc: true });
    expect(utils.getViewDateValue(component)).toEqual(expectedStrDate);
  });

  it("invalid string value", () => {
    const strDate = "invalid string",
      expectedStrDate = format(new Date(), "MMMM YYYY"),
      component = utils.createDatetime({ viewDate: strDate });
    expect(utils.getViewDateValue(component)).toEqual(expectedStrDate);
  });

  it("invalid Date object", () => {
    const date = null,
      expectedStrDate = format(new Date(), "MMMM YYYY"),
      component = utils.createDatetime({ viewDate: date });
    expect(utils.getViewDateValue(component)).toEqual(expectedStrDate);
  });

  it("viewDate -> picker should change the initial month (viewMode=months)", () => {
    const preDate = new Date(2000, 0, 15, 2, 2, 2, 2),
      strPreDate = format(preDate, "MMMM YYYY"),
      component = utils.createDatetime({ viewDate: preDate });
    expect(utils.getViewDateValue(component)).toEqual(strPreDate);

    const postDate = new Date(2010, 0, 15, 2, 2, 2, 2),
      strPostDate = format(postDate, "MMMM YYYY");
    component.setProps({ viewDate: postDate });
    expect(utils.getViewDateValue(component)).toEqual(strPostDate);
  });
});