filename ordering / exception mutation breaks exception-message-attribute

[asottile]

Steps to reproduce

I have the following minimal setup:

# a.py

def f():
    e = Exception()
    e.message = 'bang!'
    raise e

# b.py

def g():
    try:
        raise TypeError('ohai')
    except Exception as e:
        print(e.message)

Current behavior

Currently, errors are reported based on the ordering of the invocation:

$ pylint --py3k a.py b.py

--------------------------------------------------------------------
Your code has been rated at 10.00/10 (previous run: 10.00/10, +0.00)

$ pylint --py3k b.py a.py
************* Module b
b.py:7:14: W1645: Exception.message removed in Python 3 (exception-message-attribute)

------------------------------------------------------------------
Your code has been rated at 8.89/10 (previous run: 8.89/10, +0.00)

Expected behavior

I expect both to produce the error from b.py, and maybe even an error in a.py for assigning to Exception.message

pylint --version output

$ pylint --version
pylint 2.3.1
astroid 2.2.5
Python 3.6.7 (default, Oct 22 2018, 11:32:17) 
[GCC 8.2.0]

[PCManticore]

Thanks for the report! This looks like #689 but we should definitely emit the same error for both files, regardless from where the attribute came.