Hi.
I think this is a bug, or i am not getting something right on the flow of GDScript.
See, several classes have a internal ENUM, that you can use to configure function calls parameters.
Several of then are, in my understand, with a _tippo.
I will try to update this post, but i do not think this is exaustive, and i am just starting with one, but i remember others and i will keep commenting them.
If someone confirm this behaviour, its a bug, right? Then i shall report it.
Thanks for the effort in confirmation.