from jedi.evaluate.base_context import ContextSet, NO_CONTEXTS

class AbstractLazyContext(object):

def __init__(self, data):

self.data = data

def __repr__(self):

return '<%s: %s>' % (self.__class__.__name__, self.data)

def infer(self):

raise NotImplementedError

class LazyKnownContext(AbstractLazyContext):

"""data is a context."""

def infer(self):

return ContextSet(self.data)

class LazyKnownContexts(AbstractLazyContext):

"""data is a ContextSet."""

def infer(self):

return self.data

class LazyUnknownContext(AbstractLazyContext):

def __init__(self):

super(LazyUnknownContext, self).__init__(None)

def infer(self):

return NO_CONTEXTS

class LazyTreeContext(AbstractLazyContext):

def __init__(self, context, node):

super(LazyTreeContext, self).__init__(node)

self._context = context

# We need to save the predefined names. It's an unfortunate side effect

# that needs to be tracked otherwise results will be wrong.

self._predefined_names = dict(context.predefined_names)

def infer(self):

old, self._context.predefined_names = \

self._context.predefined_names, self._predefined_names

try:

return self._context.eval_node(self.data)

finally:

self._context.predefined_names = old

def get_merged_lazy_context(lazy_contexts):

if len(lazy_contexts) > 1:

return MergedLazyContexts(lazy_contexts)

else:

return lazy_contexts[0]

class MergedLazyContexts(AbstractLazyContext):

"""data is a list of lazy contexts."""

def infer(self):

return ContextSet.from_sets(l.infer() for l in self.data)