After window.XMLHttpRequest is replaced by the FakeXMLHttpRequest, accessing the readyState constants returns undefined (e.g. XMLHttpRequest.DONE => undefined).
It is available on the instances of XMLHttpRequest, or on FakeXMLHttpRequest, but any code that relies on XMLHttpRequest.DONE will be broken.
After
window.XMLHttpRequestis replaced by the FakeXMLHttpRequest, accessing thereadyStateconstants returns undefined (e.g.XMLHttpRequest.DONE=>undefined).It is available on the instances of
XMLHttpRequest, or onFakeXMLHttpRequest, but any code that relies onXMLHttpRequest.DONEwill be broken.