jasmine-mock-factory

Jasmine Mock Factory

A Jasmine test util that uses a TypeScript class or an instance of a class to create a mock instance of that class.

Quick Start

import { SomeClass } from 'some-library';
import { MockFactory} from 'jasmine-mock-factory';

it('should pass', () => {
    const mockInstance = MockFactory.create(SomeClass);
    mockInstance.doSomething.and.returnValue('awesome!');

    mockInstance.doSomething();  // returns 'awesome!'

    expect(mockInstance.doSomething).toHaveBeenCalled();
}

Prerequisite

This util is built with and for Jasmine test framework. Basic understanding of Jasmine is assumed.

This util requires ES6 Proxy and only contains un-compiled *.ts files which must be compiled with a TypeScript compiler.

Usage

Install

npm install jasmine-mock-factory --save-dev

Import

Import the library with ES6 Module Syntax:

import { MockFactory } from 'jasmine-mock-factory'

Creating a mock

From a TypeScript class

class RealClass {
  // This is a typescript class
}

...

const mockInstance = MockFactory.create(RealClass);

From an instance of a class

const realInstance: RealInterface = new RealClass();

...

const mockInstance = MockFactory.create(realInstance);

Using a mock

MockFactory.create() will return an object with the same interface as the original object. You can invoke methods and get/set properties on this object.

• All the public and private methods will have a jasmine.Spy as the initial value. The Spy cannot be overwritten.
• All the public and private properties will have undefined as the initial value. The value can be overwritten with anything.

Examples

class RealClass {
  public doSomething(...arg: any[]) { ... }
  public someProperty = 'whatever';
}

const mockInstance = MockFactory.create(RealClass);

// get, set property
expect(mockInstance.someProperty).toBeUndefined();
mockInstance.someProperty = 'hello';
expect(mockInstance.someProperty).toBe('hello');

// use function spy
expect(mockInstance.doSomething).not.toHaveBeenCalled();

(mockInstance.doSomething as jasmine.Spy).and.returnValue('awesome!');

expect(mockInstance.doSomething(42)).toBe('awesome!');
expect(mockInstance.doSomething).toHaveBeenCalledWith(42);

Develope

This project is built with Angular CLI

Running unit tests

Run ng test to execute the unit tests via Karma.