README.md

chai-subset

Important

Deprecated! This library and repository are deprecated, as the functionality is now included in chai itself. See more here.

"containSubset" object properties matcher for Chai assertion library

Installation

npm install --save-dev chai-subset

Usage

common.js

var chai = require('chai');
var chaiSubset = require('chai-subset');
chai.use(chaiSubset);

in your spec.js

var obj = {
	a: 'b',
	c: 'd',
	e: {
		foo: 'bar',
		baz: {
			qux: 'quux'
		}
	}
};
	
expect(obj).to.containSubset({
	a: 'b',
	e: {
		baz: {
			qux: 'quux'
		}
	}
});

// or using a compare function
expect(obj).containSubset({
	a: (expectedValue) => expectedValue,
	c: (expectedValue) => expectedValue === 'd'
})

// or with 'not'
expect(obj).to.not.containSubset({
	g: 'whatever'
});

Also works good with arrays and should interface

var list = [{a: 'a', b: 'b'}, {v: 'f', d: {z: 'g'}}];

list.should.containSubset([{a:'a'}]); //Assertion error is not thrown
list.should.containSubset([{a:'a',  b: 'b'}]); //Assertion error is not thrown

list.should.containSubset([{a:'a', b: 'bd'}]); 
/*throws
AssertionError: expected
[
    {
        "a": "a",
        "b": "b"
    },
    {
        "v": "f",
        "d": {
            "z": "g"
        }
    }
]
to contain subset 
[ { a: 'a', b: 'bd' } ]
*/

and with assert interface

assert.containSubset({a: 1, b: 2}, {a: 1});