Suppress special casing of attribute names in closure classes since they are not user defined and any local variable name is allowed without being special.

Closes #1797.

4 files changed, 12 insertions, 10 deletions

diff --git a/Cython/Compiler/ModuleNode.py b/Cython/Compiler/ModuleNode.py
index 2949ceeb6..311afcfb9 100644
--- a/Cython/Compiler/ModuleNode.py
+++ b/Cython/Compiler/ModuleNode.py
@@ -1334,11 +1334,11 @@ class ModuleNode(Nodes.Node, Nodes.BlockNode):
         is_final_type = scope.parent_type.is_final_type
         needs_gc = scope.needs_gc()
 
-        weakref_slot = scope.lookup_here("__weakref__")
+        weakref_slot = scope.lookup_here("__weakref__") if not scope.is_closure_class_scope else None
         if weakref_slot not in scope.var_entries:
             weakref_slot = None
 
-        dict_slot = scope.lookup_here("__dict__")
+        dict_slot = scope.lookup_here("__dict__") if not scope.is_closure_class_scope else None
         if dict_slot not in scope.var_entries:
             dict_slot = None
 
@@ -2800,7 +2800,7 @@ class ModuleNode(Nodes.Node, Nodes.BlockNode):
                             scope.class_name,
                             typeobj_cname,
                             code.error_goto(entry.pos)))
-                weakref_entry = scope.lookup_here("__weakref__")
+                weakref_entry = scope.lookup_here("__weakref__") if not scope.is_closure_class_scope else None
                 if weakref_entry:
                     if weakref_entry.type is py_object_type:
                         tp_weaklistoffset = "%s.tp_weaklistoffset" % typeobj_cname
@@ -2815,7 +2815,7 @@ class ModuleNode(Nodes.Node, Nodes.BlockNode):
                             weakref_entry.cname))
                     else:
                         error(weakref_entry.pos, "__weakref__ slot must be of type 'object'")
-                if scope.lookup_here("__reduce_cython__"):
+                if scope.lookup_here("__reduce_cython__") if not scope.is_closure_class_scope else None:
                     # Unfortunately, we cannot reliably detect whether a
                     # superclass defined __reduce__ at compile time, so we must
                     # do so at runtime.
diff --git a/Cython/Compiler/ParseTreeTransforms.py b/Cython/Compiler/ParseTreeTransforms.py
index 49b280389..e7ba2c55b 100644
--- a/Cython/Compiler/ParseTreeTransforms.py
+++ b/Cython/Compiler/ParseTreeTransforms.py
@@ -2632,6 +2632,7 @@ class CreateClosureClasses(CythonTransform):
         func_scope.scope_class = entry
         class_scope = entry.type.scope
         class_scope.is_internal = True
+        class_scope.is_closure_class_scope = True
         if Options.closure_freelist_size:
             class_scope.directives['freelist'] = Options.closure_freelist_size
 
diff --git a/Cython/Compiler/Symtab.py b/Cython/Compiler/Symtab.py
index 248e6c4bb..3ed21a47e 100644
--- a/Cython/Compiler/Symtab.py
+++ b/Cython/Compiler/Symtab.py
@@ -1917,6 +1917,7 @@ class CClassScope(ClassScope):
     #  inherited_var_entries [Entry]  Adapted var entries from base class
 
     is_c_class_scope = 1
+    is_closure_class_scope = False
 
     has_pyobject_attrs = False
     has_memoryview_attrs = False
@@ -1960,7 +1961,7 @@ class CClassScope(ClassScope):
 
         for entry in self.var_entries:
             if entry.type.is_pyobject:
-                if include_weakref or entry.name != "__weakref__":
+                if include_weakref or (self.is_closure_class_scope or entry.name != "__weakref__"):
                     if include_gc_simple or not entry.type.is_gc_simple:
                         py_attrs.append(entry)
             elif entry.type == PyrexTypes.c_py_buffer_type:
@@ -1980,7 +1981,7 @@ class CClassScope(ClassScope):
                 error(pos,
                     "C attributes cannot be added in implementation part of"
                     " extension type defined in a pxd")
-            if get_special_method_signature(name):
+            if not self.is_closure_class_scope and get_special_method_signature(name):
                 error(pos,
                     "The name '%s' is reserved for a special method."
                         % name)
@@ -1998,7 +1999,7 @@ class CClassScope(ClassScope):
                 self.has_memoryview_attrs = True
             elif type.is_cpp_class:
                 self.has_cpp_class_attrs = True
-            elif type.is_pyobject and name != '__weakref__':
+            elif type.is_pyobject and (self.is_closure_class_scope or name != '__weakref__'):
                 self.has_pyobject_attrs = True
                 if (not type.is_builtin_type
                         or not type.scope or type.scope.needs_gc()):
@@ -2011,7 +2012,7 @@ class CClassScope(ClassScope):
                 # so do conversion ourself rather than rely on the CPython mechanism (through
                 # a property; made in AnalyseDeclarationsTransform).
                 entry.needs_property = True
-                if name == "__weakref__":
+                if not self.is_closure_class_scope and name == "__weakref__":
                     error(pos, "Special attribute __weakref__ cannot be exposed to Python")
                 if not (type.is_pyobject or type.can_coerce_to_pyobject(self)):
                     # we're not testing for coercion *from* Python here - that would fail later
@@ -2056,7 +2057,7 @@ class CClassScope(ClassScope):
         return entry
 
     def lookup_here(self, name):
-        if name == "__new__":
+        if not self.is_closure_class_scope and name == "__new__":
             name = EncodedString("__cinit__")
         entry = ClassScope.lookup_here(self, name)
         if entry and entry.is_builtin_cmethod:
diff --git a/Cython/Compiler/TypeSlots.py b/Cython/Compiler/TypeSlots.py
index b25b4adb8..c764f7261 100644
--- a/Cython/Compiler/TypeSlots.py
+++ b/Cython/Compiler/TypeSlots.py
@@ -519,7 +519,7 @@ class DictOffsetSlot(SlotDescriptor):
     #  Slot descriptor for a class' dict offset, for dynamic attributes.
 
     def slot_code(self, scope):
-        dict_entry = scope.lookup_here("__dict__")
+        dict_entry = scope.lookup_here("__dict__") if not scope.is_closure_class_scope else None
         if dict_entry and dict_entry.is_variable:
             if getattr(dict_entry.type, 'cname', None) != 'PyDict_Type':
                 error(dict_entry.pos, "__dict__ slot must be of type 'dict'")