def get_changes(self, cycle):
"""
For every key that has changed since begin() was called, returns a
dictionary mapping the key to its value when begin was called, or
deleted if it did not exist when begin was called.
As a side-effect, updates self.ever_been_changed, and returns the
changes to ever_been_changed as well.
`cycle`
If true, this cycles the old changes to the new changes. If
False, does not.
"""
new = DictItems(self)
rv = find_changes(self.old, new, deleted)
if cycle:
self.old = new
if rv is None:
return None
delta_ebc = set()
if cycle:
for k in rv:
if k not in self.ever_been_changed:
self.ever_been_changed.add(k)
delta_ebc.add(k)
return rv, delta_ebc
def reset(self):
"""
Called to reset this to its initial conditions.
"""
self.ever_been_changed = set()
self.clear()
self.old = DictItems(self)
def __init__(self):
# The value of this dictionary at the start of the current
# rollback period (when begin() was last called).
self.old = DictItems(self)
# The set of variables in this StoreDict that changed since the
# end of the init phase.
self.ever_been_changed = set()
def restore_one(self, name):
sd = store_dicts[name]
sd.clear()
sd.update(self.store[name])
sd.old = DictItems(self.old[name])
sd.ever_been_changed.clear()
sd.ever_been_changed.update(self.ever_been_changed[name])
def get_changes(self):
"""
For every key that has changed since begin() was called, returns a
dictionary mapping the key to its value when begin was called, or
deleted if it did not exist when begin was called.
As a side-effect, updates self.ever_been_changed.
"""
new = DictItems(self)
rv = find_changes(self.old, new, deleted)
self.old = new
if rv is None:
return EMPTY_DICT
for k in rv:
self.ever_been_changed.add(k)
return rv
def begin(self):
"""
Called to mark the start of a rollback period.
"""
self.old = DictItems(self)