prophecy: Callcenter returns null on non registered method call

Hello,

First I do not often submit issues, so please accept my apologies if it is far from perfect. This comment https://github.com/phpspec/prophecy/pull/441/files#r388191626 is perfectly true (as often with Stof) and thus creates an exception with an imprecise message.

Where I would like to see that there was no configured methodCall for these arguments with the list of provided arguments, I have a message about type mismatch. This means to correct the error I have to look at the arguments with a debugger for instance.

I wonder if it is good to authorise a call that must return a value to fail later in case of shouldHaveBeenCalled() because it is not the job of prophecy to know/guess what to return.

I think an option is to return the good type thanks to reflection. Another option would be to check if the type of return is not void and throw the exception immediately which would mean users could not expect a shouldHaveBeenCalled to work for function with a return value without defining the correct return value themselves. There may be a lot of other better options but I only thought of these for now.

Could you please tell me where I made mistakes in my understandings. And if I’m correct about the problem how should we proceed to make this better?

PS : @everzet I’m a regular user of Prophecy and I want to thank you for this piece of software.