modified dynamic module globals get overriden at load time

[pierreglaser]

Hi all,
While introspecting test_dynamic_module for #192, I wrote a script that

• dumps a dynamic module,
• changes a global variable inside
• finally re-load the dumped module.

import imp
import cloudpickle
import textwrap
import sys
import pickle

mod = imp.new_module('mod')
code = '''
x = 1
'''
exec(textwrap.dedent(code), mod.__dict__)

# first, dump the module
fileobj = cloudpickle.dumps(mod)

# change the mod's global variable x
mod.x = 2

# create child-process-like process environnement where
# mod is already loaded with the modified variable x
sys.modules['mod'] = mod

# finally, re-load the dynamic module
mod2 = pickle.loads(fileobj)

# this fails for now
assert mod2.x == mod.x

The modified global variable gets overriden. I wonder if this is global behavior, or it needs to be changed.

Using Python 3.7.0, cloudpickle==0.5.5

[ogrisel]

This was fixed in #205.