core: do not assume controller is a method

If a controller is not a method (e.g. a staticmethod or a function),
there's no need to pop up the self argument. That actually make the
signature to mismatch, so let's fix that.

Change-Id: Ia96b7d19b2b664381e422b7182d0437b841914dd

pecan/core.py

@@ -343,7 +343,9 @@ class PecanBase(object):
         args = []
         varargs = []
         kwargs = dict()
-        valid_args = argspec.args[1:]  # pop off `self`
+        valid_args = argspec.args[:]
+        if ismethod(state.controller) or im_self:
+            valid_args.pop(0)  # pop off `self`
         pecan_state = state.request.pecan
 
         def _decode(x):

pecan/tests/test_base.py

@@ -395,6 +395,11 @@ class TestControllerArguments(PecanTestCase):
                     ', '.join(list(args) + data)
                 )
 
+            @staticmethod
+            @expose()
+            def static(id):
+                return "id is %s" % id
+
             @expose()
             def _route(self, args, request):
                 if hasattr(self, args[0]):
@@ -918,6 +923,11 @@ class TestControllerArguments(PecanTestCase):
         assert r.status_int == 200
         assert r.body == b_('variable_kwargs: list=%s' % l)
 
+    def test_staticmethod(self):
+        r = self.app_.get('/static/foobar')
+        assert r.status_int == 200
+        assert r.body == b_('id is foobar')
+
     def test_no_remainder(self):
         try:
             r = self.app_.get('/eater')