jasmine2chai

Introduction

Are you migrating your test suite from Jasmine to Mocha? Are you using chai as your assertion library in Mocha?

While Jasmine and Mocha have a very similar test and assertion syntax, they're just different enough to not work out of the box with each other.

Jasmine2Chai uses jscodeshift to (as accurately as possible) transform your test code into something that is compatible with chai.js assertions, while leaving your code style alone.

Installation

npm install -g jasmine2chai

Usage

Print out a converted file to the terminal (stdout):

jasmine2chai myfile.js

Translations

toBe -> to.be

Jasmine assertion:

expect('taco').toBe('taco');

chai assertion:

expect('taco').to.be('taco');

toEqual -> to.equal

Jasmine assertion:

expect('taco').toEqual('taco');

chai assertion:

expect('taco').to.equal('taco');

toMatch -> to.match

Jasmine assertion:

expect('taco').toMatch(/taco/)

chai assertion:

expect('taco').to.match(/taco/);

toBeDefined -> not.to.be.undefined

Jasmine assertion:

expect('taco').toBeDefined();

chai assertion:

expect('taco').to.not.be.undefined;

toBeUndefined -> to.be.undefined

Jasmine assertion:

expect(undefined).toBeUndefined();

chai assertion:

expect(undefined).to.be.undefined;

toBeNull -> to.be.null

Jasmine assertion:

expect(null).toBeNull();

chai assertion:

expect(null).to.be.null;

toBeTruthy -> to.be.ok

Jasmine assertion:

expect(true).toBeTruthy();

chai assertion:

expect(true).to.be.ok;

toBeFalsy -> to.not.be.ok

Jasmine assertion:

expect(false).toBeFalsy();

chai assertion:

expect(false).to.not.be.ok;

toContain -> to.include

Jasmine assertion:

expect([1, 2, 3]).toContain(1);

chai assertion:

expect([1, 2, 3]).to.include(1);

toBeLessThan -> to.be.below

Jasmine assertion:

expect(1).toBeLessThan(2);

chai assertion:

expect(1).to.be.below(2);

toBeGreaterThan -> to.be.above;

Jasmine assertion:

expect(2).toBeGreaterThan(1);

chai assertion:

expect(2).to.be.above(1);

toBeCloseTo -> to.be.closeTo

Jasmine assertion:

expect(2).toBeCloseTo(1,1);

chai assertion:

expect(2).to.be.closeTo(1,1);

toThrow -> to.throw

Jasmine assertion:

expect(function() { throw new Error('hi')).toThrow();

chai assertion:

expect(function() { throw new Error('hi')).to.throw();

toThrowError -> to.throw

Jasmine assertion:

expect(foo).toThrowError("foo bar baz");
expect(foo).toThrowError(/bar/);
expect(foo).toThrowError(TypeError);
expect(foo).toThrowError(TypeError, "foo bar baz");

chai assertion:

expect(foo).to.throw("foo bar baz");
expect(foo).to.throw(/bar/);
expect(foo).to.throw(TypeError);
expect(foo).to.throw(TypeError, "foo bar baz");

Spy Migrations

Important Note:

You'll need the sinon-chai plugins for this to work. In addition, spyOn calls are not yet translated. This only translates the assertions on spies.

toHaveBeenCalled -> to.have.been.called

Jasmine assertion:

expect(foo.setBar).toHaveBeenCalled();

chai assertion:

expect(foo.setBar).to.have.been.called;

toHaveBeenCalledWith -> to.have.been.calledWith

Jasmine assertion:

expect(foo.setBar).toHaveBeenCalledWith(123);
expect(foo.setBar).toHaveBeenCalledWith(456, 'another param');

chai assertion:

expect(foo.setBar).to.have.been.calledWith(123);
expect(foo.setBar).to.have.been.calledWith(456, 'another param');

toHaveBeenCalledTimes -> to.have.callCount

Jasmine assertion:

expect(foo.setBar).toHaveBeenCalledTimes(2);

chai assertion:

expect(foo.setBar).to.have.callCount(2);