revert restriction to eventonly predicates, allow a predicate to receive all args

2 files changed, 27 insertions, 4 deletions

diff --git a/src/pyramid/config/adapters.py b/src/pyramid/config/adapters.py
index 08bfff142..8a043cf56 100644
--- a/src/pyramid/config/adapters.py
+++ b/src/pyramid/config/adapters.py
@@ -45,13 +45,17 @@ class AdaptersConfiguratorMixin:
             predlist = self.get_predlist('subscriber')
             order, preds, phash = predlist.make(self, **predicates)
 
-            derived_subscriber = self._derive_subscriber(subscriber, preds)
+            derived_predicates = [self._derive_predicate(p) for p in preds]
+            derived_subscriber = self._derive_subscriber(
+                subscriber, derived_predicates
+            )
 
             intr.update(
                 {
                     'phash': phash,
                     'order': order,
                     'predicates': preds,
+                    'derived_predicates': derived_predicates,
                     'derived_subscriber': derived_subscriber,
                 }
             )
@@ -71,6 +75,19 @@ class AdaptersConfiguratorMixin:
         self.action(None, register, introspectables=(intr,))
         return subscriber
 
+    def _derive_predicate(self, predicate):
+        if eventonly(predicate):
+
+            def derived_predicate(*arg):
+                return predicate(arg[0])
+
+            # seems pointless to try to fix __doc__, __module__, etc as
+            # predicate will invariably be an instance
+        else:
+            derived_predicate = predicate
+
+        return derived_predicate
+
     def _derive_subscriber(self, subscriber, predicates):
         if eventonly(subscriber):
 
@@ -104,7 +121,7 @@ class AdaptersConfiguratorMixin:
             # with all args, the eventonly hack would not have been required.
             # At this point, though, using .subscriptions and manual execution
             # is not possible without badly breaking backwards compatibility.
-            if all(predicate(arg[0]) for predicate in predicates):
+            if all(predicate(*arg) for predicate in predicates):
                 return derived_subscriber(*arg)
 
         if hasattr(subscriber, '__name__'):
@@ -309,4 +326,7 @@ class AdaptersConfiguratorMixin:
 
 
 def eventonly(callee):
-    return takes_one_arg(callee, argname='event')
+    # we do not count a function as eventonly if it accepts *args
+    # which will open up the possibility for the function to receive
+    # all of the args
+    return takes_one_arg(callee, argname='event', allow_varargs=False)
diff --git a/src/pyramid/util.py b/src/pyramid/util.py
index f396712f3..c71528a49 100644
--- a/src/pyramid/util.py
+++ b/src/pyramid/util.py
@@ -652,7 +652,7 @@ def make_contextmanager(fn):
     return wrapper
 
 
-def takes_one_arg(callee, attr=None, argname=None):
+def takes_one_arg(callee, attr=None, argname=None, allow_varargs=True):
     ismethod = False
     if attr is None:
         attr = '__call__'
@@ -679,6 +679,9 @@ def takes_one_arg(callee, attr=None, argname=None):
     if not args:
         return False
 
+    if not allow_varargs and argspec.varargs:
+        return False
+
     if len(args) == 1:
         return True