Testing tools for React based applications

Install

npm install @viperhq/react-test-tools

Extend Global

Open jest.setup.ts or any setupFilesAfterEnv setup file where you can access the global used in tests.

import { extendGlobal } from "react-test-tools";

// Enables jest based functionality
extendGlobal("jest");

Global type definitions

Open tsconfig.json used in tests and add an include:

{
  "include": ["node_modules/@viperhq/react-test-tools/global.d.ts"]
}

Usage

Mocked

It allows you to Mock objects in a type safer way.

You can reset the object to default value using resetAllMocks().

Example:

type Mockable = {
  foo: {
    bar: {
      baz: false;
      baz2: true;
    };
    bar2: string;
    fn: () => number;
    arr: ["42"];
    map: Map<string, string>;
    set: Set<string>;
  };
  foo2: number;
};

describe("test", () => {
  const mockable = Mocked<Mockable>({
    foo2: 42,
    foo: {
      fn: jest.fn(),
    },
  });

  beforeEach(() => {
    mockable.resetAllMocks();
    mockable.foo.fn.mockImplementation(() => 42);
  });

  it("should be 42", () => {
    expect(mockable.foo.fn()).toEqual(42);
    mockable.foo2 = 43;
  });

  it("should be 42 here too", () => {
    expect(mockable.foo2).toEqual(42);
  });
});

Caveats with Mocked objects

• Values cannot be cloned keep their state on reset. jest.fn() mocks can be reseted if extendGlobal called with the parameter "jest".

• Mocked objects cannot be nested at the moment.