1 files changed, 22 insertions, 7 deletions
diff --git a/src/mailman/app/finder.py b/src/mailman/app/finder.py
index 41685730a..bd1305c21 100644
--- a/src/mailman/app/finder.py
+++ b/src/mailman/app/finder.py
@@ -22,6 +22,7 @@ from __future__ import absolute_import, unicode_literals
 __metaclass__ = type
 __all__ = [
     'find_components',
+    'scan_module',
     ]
 
 
@@ -32,6 +33,25 @@ from pkg_resources import resource_listdir
 
 
 
+def scan_module(module, interface):
+    """Return all the items in a module that conform to an interface.
+
+    :param module: A module object.  The module's `__all__` will be scanned.
+    :type module: module
+    :param interface: The interface that returned objects must conform to.
+    :type interface: `Interface`
+    :return: The sequence of matching components.
+    :rtype: objects implementing `interface`
+    """
+    missing = object()
+    for name in module.__all__:
+        component = getattr(module, name, missing)
+        assert component is not missing, (
+            '%s has bad __all__: %s' % (module, name))
+        if interface.implementedBy(component):
+            yield component
+
+
 def find_components(package, interface):
     """Find components which conform to a given interface.
 
@@ -54,10 +74,5 @@ def find_components(package, interface):
         module = sys.modules[module_name]
         if not hasattr(module, '__all__'):
             continue
-        for name in module.__all__:
-            missing = object()
-            component = getattr(module, name, missing)
-            assert component is not missing, (
-                '%s has bad __all__: %s' % (module, name))
-            if interface.implementedBy(component):
-                yield component
+        for component in scan_module(module, interface):
+            yield component