# HG changeset patch
# User Paul Boddie <paul@boddie.org.uk>
# Date 1481236394 -3600
# Node ID 19b30b3612e7eb72e1493a898c04c7b06a3a881a
# Parent  4849542ef9da9f43070e7c2e503112292a1c9752
Ensure that deduced types for "self" include the class of the method involved.

diff -r 4849542ef9da -r 19b30b3612e7 deducer.py
--- a/deducer.py	Thu Dec 08 23:30:24 2016 +0100
+++ b/deducer.py	Thu Dec 08 23:33:14 2016 +0100
@@ -23,7 +23,7 @@
                    get_attrname_from_location, get_attrnames, \
                    get_invoked_attributes, get_name_path, init_item, \
                    sorted_output, CommonOutput
-from encoders import encode_attrnames, encode_access_location, \
+from encoders import encode_access_location, \
                      encode_constrained, encode_location, encode_usage, \
                      get_kinds, test_label_for_kind, test_label_for_type
 from errors import DeduceError
@@ -1315,6 +1315,17 @@
         # Constrain "self" references.
 
         if name == "self":
+
+            # Test for the class of the method in the deduced types.
+
+            class_name = self.in_method(unit_path)
+
+            if class_name and class_name not in class_types and class_name not in only_instance_types:
+                raise DeduceError("In %s, usage {%s} is not directly supported by class %s or its instances." %
+                                  (unit_path, encode_usage(usage), class_name))
+
+            # Constrain the types to the class's hierarchy.
+
             t = self.constrain_self_reference(unit_path, class_types, only_instance_types)
             if t:
                 class_types, only_instance_types, module_types, constrained = t