@applicaster/zapp-react-dom-app/App/Loader/utils/__tests__/getLanguageCode.test.js

Zapp App Component for Applicaster's Quick Brick React Native App

import { getLanguageCodeImpl as getLanguageCode } from "..";

describe("getLanguageCode", () => {
  it("return best matched language", async () => {
    // setup
    const getLanguageCodeFromLocalStorage = jest
      .fn()
      .mockResolvedValueOnce(undefined);

    const getAvailableAppLanguages = jest
      .fn()
      .mockReturnValue(["en", "fr", "ru"]);

    const pickBestMatchedLanguage = jest.fn().mockReturnValue("ru");
    const setLanguageCodeToLocalStorage = jest.fn().mockResolvedValueOnce(true);

    const locale = "ru";

    // run
    const result = await getLanguageCode(
      getLanguageCodeFromLocalStorage,
      getAvailableAppLanguages,
      pickBestMatchedLanguage,
      setLanguageCodeToLocalStorage
    )(locale);

    // verify
    expect(result).toEqual(locale);
  });

  it("return value from local-storage", async () => {
    // setup
    const getLanguageCodeFromLocalStorage = jest
      .fn()
      .mockResolvedValueOnce("value-from-local-storage");

    const getAvailableAppLanguages = jest.fn();
    const pickBestMatchedLanguage = jest.fn();
    const setLanguageCodeToLocalStorage = jest.fn();

    const locale = "ru";

    // run
    const result = await getLanguageCode(
      getLanguageCodeFromLocalStorage,
      getAvailableAppLanguages,
      pickBestMatchedLanguage,
      setLanguageCodeToLocalStorage
    )(locale);

    // verify
    expect(result).toEqual("value-from-local-storage");
    expect(getAvailableAppLanguages).not.toHaveBeenCalled();
    expect(pickBestMatchedLanguage).not.toHaveBeenCalled();
    expect(setLanguageCodeToLocalStorage).not.toHaveBeenCalled();
  });
});