to.have.property not detects undefined fields

[sonicoder86]

The property matcher behaves not consistently for undefined values

var obj = { x: undefined, y: 1}
expect(obj).to.have.property('x') // not pass

but checking like this:

expect(Object.getOwnPropertyNames(obj)).to.contain('x') // pass

[keithamus]

Hey @BlackSonic thanks for the issue.

This issue is actually a duplicate of #184 - which was fixed in Chai 2.0.0. It was fixed in PR #308 if you're curious.

Here's a code sample of it working in Chai 2.0.0:

> var obj = { x: undefined, y: 1}
undefined
> expect(obj).to.have.property('x')
{ __flags: { ssfi: [Function], object: undefined, message: undefined } }

Also, if you need the behaviour to work for older version of chai, you can opt to use the ownProperty assertion instead, I believe.

expect(obj).to.have.ownProperty('x')

ownProperty doesn't pass the property value over though, so you cannot chain it in the same way.

I'm going to close this issue - because of the above. If you still feel it is a problem, let me know and I'll reopen it 😄

[sonicoder86]

thanks, upgrading to new version solved the issue