Fix signatures for wraps, see #1058

jedi/evaluate/signature.py

@@ -30,12 +30,6 @@ class _SignatureMixin(object):
             s += ' -> ' + annotation
         return s
 
-    def get_param_names(self, resolve_stars=True):
-        param_names = self._function_context.get_param_names()
-        if self.is_bound:
-            return param_names[1:]
-        return param_names
-
 
 class AbstractSignature(_SignatureMixin):
     def __init__(self, context, is_bound=False):
@@ -50,6 +44,12 @@ class AbstractSignature(_SignatureMixin):
     def annotation_string(self):
         return ''
 
+    def get_param_names(self, resolve_stars=True):
+        param_names = self._function_context.get_param_names()
+        if self.is_bound:
+            return param_names[1:]
+        return param_names
+
     def bind(self, context):
         raise NotImplementedError