PromiseInterface has not done object

Taking a look a this line done method does not exist for a React\Promise\PromiseInterface

Line 335 in 10e34de

$this->flushWriteBuffer()->done(function () {

It has produces some errors in my project

In Client.php line 340:

Attempted to call an undefined method named "done" of class "React\Promise\Promise".

This package doesn't target promise v3 yet:

Line 30 in 10e34de

"react/promise": "~2.2"

So how are you getting that error?

P.S. Don't get me wrong, happy to see more and more people using Promise v3 but that shouldn't happen when you use this package yet.

Closing this as #147 landed promise v3 for the upcoming 0.6 release