Raise exception if handler.list() type doesn't exist

src/cement2/cement2/core/foundation.py

@@ -690,6 +690,10 @@ def _setup_controllers(self):
             self.controller = self._resolve_handler('controller', 
                                                     self._meta.base_controller) 
             self._meta.base_controller = self.controller
+        elif self._meta.base_controller is None:
+            if handler.registered('controller', 'base'):
+                self.controller = self._resolve_handler('controller', 'base') 
+                self._meta.base_controller = self.controller
 
         # Trump all with whats passed at the command line, and pop off the arg
         if len(self.argv) > 0:

src/cement2/cement2/core/handler.py

@@ -106,6 +106,10 @@ def list(handler_type):
             The type of handler (i.e. 'output')
     
     """
+    if handler_type not in backend.handlers:
+        raise exc.CementRuntimeError("handler type '%s' does not exist!" % \
+                                     handler_type)
+
     res = []
     for label in backend.handlers[handler_type]:
         if label == '__interface__':

src/cement2/tests/core/controller_tests.py

@@ -241,6 +241,14 @@ def test_base_controller(self):
         self.app.setup()
         self.app.run()
 
+    def test_base_controller_by_name(self):
+        self.app = _t.prep(
+            argv=['my-command'], 
+            base_controller=None
+            )
+        handler.register(TestBaseController)
+        self.app.setup()
+
     def test_stacked_controller(self):
         app = _t.prep(
             argv=['my-stacked-command',], 

src/cement2/tests/core/handler_tests.py

@@ -5,6 +5,7 @@
 from cement2.core import exc, backend, handler, handler, output, meta
 from cement2.core import interface
 from cement2 import test_helper as _t
+from cement2.lib.ext_configparser import ConfigParserConfigHandler
 
 class BogusOutputHandler(meta.MetaMixin):
     class Meta:
@@ -109,6 +110,17 @@ def test_handler_defined(self):
         # and check for bogus one too
         eq_(handler.defined('bogus'), False)
 
+    def test_handler_list(self):
+        self.app.setup()
+        handler_list = handler.list('config')
+        res = ConfigParserConfigHandler in handler_list
+        ok_(res)
+
+    @raises(exc.CementRuntimeError)
+    def test_handler_list_bogus_type(self):
+        self.app.setup()
+        handler_list = handler.list('bogus')
+
     def is_defined(handler_type):
         eq_(handler.defined(handler_type), True)