fix issue #17 by considering only routines as hooks

Author: RonnyPfannschmidt

CHANGELOG

@@ -4,6 +4,10 @@
 - fix bug where callbacks for historic hooks would not be called for
   already registered plugins.  Thanks Simon Gmizelj for the PR
   and holger krekel for further fixes.
+- fix #17 by considering only actual functions for hooks
+  this removes the ability to register arbitrary callable objects
+  which at first glance is a reasonable simplification,
+  thanks RonnyPfannschmidt for report and pr.
 
 0.4.0
 -----

pluggy.py

@@ -375,6 +375,8 @@ def register(self, plugin, name=None):
 
     def parse_hookimpl_opts(self, plugin, name):
         method = getattr(plugin, name)
+        if not inspect.isroutine(method):
+            return
         try:
             res = getattr(method, self.project_name + "_impl", None)
         except Exception:

testing/test_pluggy.py

@@ -660,17 +660,12 @@ def test_prefix_hookimpl_dontmatch_module(self):
         pm = PluginManager(hookspec.project_name, "hello_")
 
         class BadPlugin:
-            def hello_fine(self):
-                pass
-            hello_fine.optionalhook = True
-
             hello_module = __import__('email')
 
         pm.register(BadPlugin())
         pm.check_pending()
 
 
-
 def test_parse_hookimpl_override():
     class MyPluginManager(PluginManager):
         def parse_hookimpl_opts(self, module_or_class, name):