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# (C) Copyright 2005-2025 Enthought, Inc., Austin, TX
# All rights reserved.
#
# This software is provided without warranty under the terms of the BSD
# license included in LICENSE.txt and may be redistributed only under
# the conditions described in the aforementioned license. The license
# is also available online at http://www.enthought.com/licenses/BSD.txt
#
# Thanks for using Enthought open source!
class Foo0:
""" The original class written with no expectation of being upgraded """
def __init__(self):
self.prenom = 'didier'
self.surnom = 'enfant'
class Foo1:
""" Now to handle both Foo v0 and Foo v1 we need to add more code ..."""
def __init__(self, firstname, lastname):
""" This does not get called when the class is unpickled."""
self.firstname = firstname
self.lastname = lastname
class Foo:
def __str__(self):
result = ['----------------------------------------------------------']
keys = dir(self)
for key in keys:
result.append('%s ---> %s' % (key, getattr(self, key)))
result.append('------------------------------------------------------')
return '\n'.join(result)
def __setstate__(self, state):
print('calling setstate on the real Foo')
state['set'] = True
self.__dict__.update(state)
def save(fname, str):
f = open(fname, 'w')
f.write(str)
f.close()
if __name__ == '__main__':
# Create dummy test data .......
import pickle
obj = Foo0()
print(obj)
t0 = pickle.dumps(obj)
save('foo0.txt', t0)
'''obj = Foo1('duncan', 'child')
t1 = pickle.dumps(obj).replace('Foo1', 'Foo')
save('foo1.txt', t1)
obj = Foo2('duncan child')
t2 = pickle.dumps(obj).replace('Foo2', 'Foo')
save('foo2.txt', t2)
obj = Foo3('duncan child')
t3 = pickle.dumps(obj).replace('Foo3', 'Foo')
save('foo3.txt', t3)
'''
print('==================================================================')
from apptools.persistence.versioned_unpickler import VersionedUnpickler
# Try and read them back in ...
f = open('foo0.txt')
import sys
rev = 1
__import__('integrationtests.persistence.update%d' % rev)
mod = sys.modules['integrationtests.persistence.update%d' % rev]
klass = getattr(mod, 'Update%d' % rev)
updater = klass()
print('%s %s' % (rev, updater))
p = VersionedUnpickler(f, updater).load()
print(p)
print('Restored version %s %s' % (p.lastname, p.firstname))
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