chai-to-jasmine

This repository has been depreciated by a contribution to https://github.com/skovhus/jest-codemods. All future updates and bug fixes will live on in the jest-codemods repository.

A jscodeshift codemod that transforms test files from chai to Jasmine.

Install & Run

npm install -g jscodeshift
git clone https://github.com/AlexJuarez/chai-to-jasmine.git
jscodeshift -t ./transforms/chai-to-jasmine <file>

Supported Chai Assertions

• calls

keys, a, an, instanceof, lengthof, length, equal, throw,
include, contain, eql, above, least, below, most, match,
string, members, property, ownproperty, ownpropertydescriptor,
gte, lte

• members

ok, true, false, null, undefined, exist, empty, nan

Unsupported Chai Assertions

oneOf, change, increase, decrease

Quirks

.keys

.any is not currently supported, e.g. the following code will not correctly be converted

expect([1, 3, 4]).to.have.any.keys(1, 2);

Example Input

expect([1, 2, 3]).to.have.all.keys(1, 2);
expect({ foo: 1, bar: 2 }).to.have.all.keys({'bar': 6, 'foo': 7});
expect({ foo: 1, bar: 2, baz: 3 }).to.contain.all.keys(['bar', 'foo']);
expect({ foo: 1, bar: 2, baz: 3 }).to.contain.all.keys({'bar': 6});

Example Output

expect([1, 2, 3]).toEqual(jasmine.arrayContaining([1, 2]));
expect(Object.keys({ foo: 1, bar: 2 })).toEqual(jasmine.arrayContaining(Object.keys({'bar': 6, 'foo': 7})));
expect(Object.keys({ foo: 1, bar: 2, baz: 3 })).toEqual(jasmine.arrayContaining(['bar', 'foo']));
expect(Object.keys({ foo: 1, bar: 2, baz: 3 })).toEqual(jasmine.arrayContaining(Object.keys({'bar': 6})));

.a|.an

The converted form uses typeof to make the type checking, some of the chai types will not be correctly checked.

Example

Correctish output

// Input
expect('test').to.be.a('string');
expect({ foo: 'bar' }).to.be.an('object');
expect(null).to.be.a('null');
expect(undefined).to.be.an('undefined');
// Correct Output
expect(typeof 'test').toBe('string');
expect(typeof { foo: 'bar' }).toBe('object');
expect(null).toBeNull();
expect(undefined).toBeUndefined();
// Input that may not work
expect(new Error).to.be.an('error');
expect(new Promise).to.be.a('promise');
expect(new Float32Array()).to.be.a('float32array');
expect(Symbol()).to.be.a('symbol');
// Output that may not work
expect(typeof new Error).toBe('error');
expect(typeof new Promise).toBe('promise');
expect(typeof new Float32Array()).toBe('float32array');
expect(typeof Symbol()).toBe('symbol');

.property

Does not support deeply nested property checks. The following code will not be correctly converted.

expect(deepObj).to.have.deep.property('green.tea', 'matcha');