Fix get_caller_name

[T4rk1n]

Fix get_caller_name by always taking the third stack frame from the function call. (0 is get_caller_name, __init__ is 1 then next one is the app = Dash() call)

[T4rk1n]

Taking by index doesn't work in the case of a custom dash class.

Think we can do with a check on the function name, it is get_caller then a chain of __init__ and we are looking for <module> which has a name.

[alexcjohnson]

💃 This looks good to me!

Note that there's at least one case where this can give a different result from app = Dash(__name__): if you create app in a function that you call from a different module. The inferred root will be the last time you were at the module scope before calling a function. You could construct some very strange situations here - a function imports a module, and that module calls a function that creates the dash app... but it feels to me as though in all those situations you should really be passing in __name__ from the user code anyway, so what you have is the right solution.

[T4rk1n]

but it feels to me as though in all those situations you should really be passing in name

Yes I think in those cases you would want to give what is appropriate by either passing the __name__ from the module or in a function argument.