fix constant folding

vyper/semantics/analysis/constant_folding.py

@@ -131,10 +131,11 @@ def visit_UnaryOp(self, node):
 
     def visit_BinOp(self, node):
         left, right = [i.get_folded_value() for i in (node.left, node.right)]
-        if type(left) is not type(right):
-            raise UnfoldableNode("invalid operation", node)
-        if not isinstance(left, vy_ast.Num):
+        valid_integer_nodes = (vy_ast.Hex, vy_ast.Int)
+        if not type(left) not in valid_integer_nodes:
             raise UnfoldableNode("not a number!", node.left)
+        if not type(right) not in valid_integer_nodes:
+            raise UnfoldableNode("invalid operation", node)
 
         # this validation is performed to prevent the compiler from hanging
         # on very large shifts and improve the error message for negative

vyper/semantics/analysis/utils.py

@@ -306,6 +306,7 @@ def types_from_Constant(self, node):
                 if not isinstance(node, t._valid_literal):
                     continue
 
+                print("type: ", t)
                 # special handling for bytestrings since their
                 # class objects are in the type map, not the type itself
                 # (worth rethinking this design at some point.)
@@ -315,7 +316,7 @@ def types_from_Constant(self, node):
                 # any more validation which needs to occur
                 t.validate_literal(node)
                 types_list.append(t)
-            except VyperException:
+            except VyperException as e:
                 continue
 
         if types_list: