Make MetaType extend ABCMeta

tests/gof/test_graph.py

@@ -30,6 +30,9 @@ class MyType(Type):
     def __init__(self, thingy):
         self.thingy = thingy
 
+    def filter(self, *args, **kwargs):
+        raise NotImplementedError()
+
     def __eq__(self, other):
         return isinstance(other, MyType) and other.thingy == self.thingy
 

tests/gof/test_toolbox.py

@@ -12,6 +12,9 @@ class TestNodeFinder:
             def __init__(self, name):
                 self.name = name
 
+            def filter(self, *args, **kwargs):
+                raise NotImplementedError()
+
             def __str__(self):
                 return self.name
 

theano/gof/utils.py

 import linecache
 import sys
 import traceback
+from abc import ABCMeta
 from io import StringIO
 
 
@@ -157,7 +158,7 @@ class MethodNotDefined(Exception):
     """
 
 
-class MetaType(type):
+class MetaType(ABCMeta):
     def __new__(cls, name, bases, dct):
         props = dct.get("__props__", None)
         if props is not None:
@@ -220,7 +221,7 @@ class MetaType(type):
 
                 dct["__str__"] = __str__
 
-        return type.__new__(cls, name, bases, dct)
+        return super().__new__(cls, name, bases, dct)
 
 
 class MetaObject(metaclass=MetaType):