but SUCCESS has a corresponding subclassed Exception."""
@classmethod
- def get_subclass_exc(cls, status, message=None):
+ def get_exc_subclass(cls, status):
"""Returns a fine grained Exception() type,detailing the error status"""
subclasses = {
STATUS.OUT_OF_MEMORY: OutOfMemoryError,
STATUS.NOT_INITIALIZED: NotInitializedError
}
assert 0 < status <= len(subclasses)
- return subclasses[status](status, message)
-
- def __init__(self, status, message=None):
+ return subclasses[status]
+
+ def __new__(cls, *args, **kwargs):
+ """Return a correct subclass of NotmuchError if needed
+
+ We return a NotmuchError instance if status is None (or 0) and a
+ subclass that inherits from NotmuchError depending on the
+ 'status' parameter otherwise."""
+ # get 'status'. Passed in as arg or kwarg?
+ status = args[0] if len(args) else kwargs.get('status', None)
+ # no 'status' or cls is subclass already, return 'cls' instance
+ if not status or cls != NotmuchError:
+ return super(NotmuchError, cls).__new__(cls)
+ subclass = cls.get_exc_subclass(status) # which class to use?
+ return subclass.__new__(subclass, *args, **kwargs)
+
+ def __init__(self, status=None, message=None):
self.status = status
self.message = message
return 'Unknown error'
# List of Subclassed exceptions that correspond to STATUS values and are
-# subclasses of NotmuchError:
+# subclasses of NotmuchError.
class OutOfMemoryError(NotmuchError):
pass
class ReadOnlyDatabaseError(NotmuchError):