sinon library extension to stub whole object and interfaces


Keywords
typescript, node, sinon, ts-sinon, interface stub, interface mock, typescript stub, stub, typescript sinon
License
MIT
Install
npm install ts-sinon@1.2.0

Documentation

ts-sinon

Sinon extension providing functions to:

  • stub all object methods
  • stub interface
  • stub object constructor

Prerequisites

  1. You have a version of Node.js >= v8.4.0
  2. You have installed Typescript

Installation

npm install --save-dev ts-sinon or yarn add --dev ts-sinon

Object stubs example

Importing stubObject function:

  • import single function:
import { stubObject } from "ts-sinon";
  • import as part of sinon singleton:
import * as sinon from "ts-sinon";

const stubObject = sinon.stubObject;

Stub all object methods:

class Test {
    method() { return 'original' }
}

const test = new Test();
const testStub = stubObject<Test>(test);

testStub.method.returns('stubbed');

expect(testStub.method()).to.equal('stubbed');

Partial stub:

class Test {
    methodA() { return 'A: original' }
    methodB() { return 'B: original' }
}

const test = new Test();
const testStub = stubObject<Test>(test, ['methodA']);

expect(testStub.methodA()).to.be.undefined;
expect(testStub.methodB()).to.equal('B: original');

Stub with predefined return values (deprecated - see the deprecation note):

class Test {
    method() { return 'original' }
}

const test = new Test();
const testStub = stubObject<Test>(test, { method: 'stubbed' });

expect(testStub.method()).to.equal('stubbed');

Interface stubs example

Importing stubInterface function:

  • import single function:
import { stubInterface } from "ts-sinon";
  • import as part of sinon singleton:
import * as sinon from "ts-sinon";

const stubInterface = sinon.stubInterface;

Interface stub (stub all methods):

interface Test {
    method(): string;
}

const testStub = stubInterface<Test>();

expect(testStub.method()).to.be.undefined;

testStub.method.returns('stubbed');

expect(testStub.method()).to.equal('stubbed');

Interface stub with predefined return values (deprecated - see the deprecation note):

interface Test {
    method(): string;
}

const testStub = stubInterface<Test>({ method: 'stubbed' });

expect(testStub.method()).to.equal('stubbed');

Object constructor stub example

Importing stubConstructor function:

  • import single function:
import { stubConstructor } from "ts-sinon";
  • import as part of sinon singleton:
import * as sinon from "ts-sinon";

const stubConstructor = sinon.stubConstructor;

Object constructor stub (stub all methods):

  • without passing predefined args to the constructor:
class Test {
    public someVar: number = 10;

    method(): string {
        return 'value';
    }
}

// type will be guessed automatically
const testStub = stubConstructor(Test);

expect(testStub.method()).to.be.undefined;

testStub.method.returns('stubbed');

expect(testStub.method()).to.equal('stubbed');

expect(testStub.someVar).to.equal(10);

testStub.someVar = 20;

expect(testStub.someVar).to.equal(20);
  • with passing predefined args to the constructor:
class Test {
    constructor(public someVar: string, y: boolean) {}

    // ...
}

// it won't allow to pass incorrect args
const testStub = stubConstructor(Test, "someVar value", true);

expect(testStub.someVar).to.equal("someValue");

Method map argument deprecation note

Due to a potential risk of overwriting return value type of stubbed method (that won't be caught by TypeScript compiler) I have decided to mark it as deprecated. Please look at the following example of type overwriting using method map:

interface ITest {
    method1(): void;
    method2(num: number): string;
}

const interfaceStub: ITest = stubInterface<ITest>({
    method2: 12345
});

// following expression will assign 12345 value of type number to v variable which is incorrect (it will compile without an error)
const v: string = interfaceStub.method2(1);

Sinon methods

By importing 'ts-sinon' you have access to all sinon methods.

import sinon, { stubInterface } from "ts-sinon";

const functionStub = sinon.stub();
const spy = sinon.spy();
// ...

or

import * as tsSinon from "ts-sinon"

const functionStub = tsSinon.default.stub();
const spy = tsSinon.default.spy();
const tsStubInterface = tsSinon.stubInterface<T>();

// ...

Packages

Dependencies:
  1. Microsoft/TypeScript
  2. TypeStrong/ts-node
  3. sinonjs/sinon
Dev Dependencies:
  1. mochajs/mocha
  2. chaijs/chai
  3. domenic/sinon-chai

Tests

npm test