Chain .property() assertions on objects

Hello,

is there a workaround to allow something like this:

chai.expect({ foo: 'bar', bar: 'foo' })
  .to.have.property('foo', 'bar')
  .and.to.have.property('bar', 'foo')
  ;

[keithamus]

I just remembered that we have .include which can test subset bodies:

chai.expect({ foo: 'bar', bar: 'foo', baz: 'bing' }).to.include({ foo: 'bar', bar: 'foo' });

This should be suitable for testing many properties. You can even combine it with property for complex nesting:

var multiLayerObject = {
    foo: {
        bar: 1,
        baz: 2,
    },
    bing: 3,
    bong: 4,
};
chai.expect(multiLayerObject)
  .to.include({ bing: 3, bong: 4 })
  .and.have.property('foo').include({ bar: 1 });

[keithamus]

I quite like the idea of also… but it needs some more discussion to fill gaps; for example I can see people expecting to traverse deep objects like so:

var multiLayerObject = {
    foo: {
        bar: 1,
        baz: 2,
    },
    bing: {
        bong: 3
        bash: 4
    }
};

// Does it just go up a level?
expect(multiLayerObject).to.have.property('foo')
    .and.have.property('bar', 1)
    .and.also.have.property('baz', 2)
  .and.also.also.have.property('bing') // ???
    .and.have.property('bong', 3)
    .and.also.have.property('bash', 4);

// Or does it reset to the originally object within expect()?
expect(multiLayerObject).to.have.deep.property('foo.bar', 1)
    .and.also.have.deep.property('foo.baz', 2)
    .and.also.have.deep.property('bing.bong', 3)
    .and.also.have.deep.property('bing.bash', 4);

At the risk of sounding cynical - I can see either implementation getting a few issues springing up discussing semantics and trying to alter them to the users use-case.

Also worth pointing out that .property() isn’t the only thing that sets the object to a new one; .throw() and .ownPropertyDescriptor() do this too - and potentially more will. We’ll need a solution that works for all of these I believe.