From f0ee02a039831301b0e5c98c3e6e98a264bf8326 Mon Sep 17 00:00:00 2001
From: Iuri de Silvio <iurisilvio@gmail.com>
Date: Wed, 30 Jul 2014 16:21:19 -0300
Subject: [PATCH 1/2] Handler raise a NoFeatureFlagFound instead of handle the
 problem.

Trigger the missing feature behaviour only if the feature wasn't
found in any handler.
---
 flask_featureflags/__init__.py | 27 +++++++++++++++++++--------
 1 file changed, 19 insertions(+), 8 deletions(-)

diff --git a/flask_featureflags/__init__.py b/flask_featureflags/__init__.py
index 7cde935..854627f 100644
--- a/flask_featureflags/__init__.py
+++ b/flask_featureflags/__init__.py
@@ -35,6 +35,11 @@ class StopCheckingFeatureFlags(Exception):
   pass
 
 
+class NoFeatureFlagFound(Exception):
+  """ Raise this when the feature flag does not exist. """
+  pass
+
+
 def AppConfigFlagHandler(feature=None):
   """ This is the default handler. It checks for feature flags in the current app's configuration.
 
@@ -63,11 +68,7 @@ class DevelopmentConfig(Config):
   try:
     return current_app.config[FEATURE_FLAGS_CONFIG][feature]
   except (AttributeError, KeyError):
-    if current_app.debug and current_app.config.get(RAISE_ERROR_ON_MISSING_FEATURES, False):
-      raise KeyError(u"No feature flag defined for {feature}".format(feature=feature))
-    else:
-      log.info(u"No feature flag defined for {feature}".format(feature=feature))
-      return False
+    raise NoFeatureFlagFound()
 
 
 class FeatureFlag(object):
@@ -93,7 +94,6 @@ def init_app(self, app):
     else:
       app.jinja_env.tests[self.JINJA_TEST_NAME] = self.check
 
-
     if not hasattr(app, 'extensions'):
       app.extensions = {}
     app.extensions[EXTENSION_NAME] = self
@@ -119,14 +119,25 @@ def check(self, feature):
     The order of handlers matters - we will immediately return True if any handler returns true.
 
     If you want to a handler to return False and stop the chain, raise the StopCheckingFeatureFlags exception."""
+    found = False
     for handler in self.handlers:
       try:
         if handler(feature):
            return True
       except StopCheckingFeatureFlags:
         return False
-    else:
-      return False
+      except NoFeatureFlagFound:
+        pass
+      else:
+        found = True
+
+    if not found:
+      if current_app.debug and current_app.config.get(RAISE_ERROR_ON_MISSING_FEATURES, False):
+        raise KeyError(u"No feature flag defined for {feature}".format(feature=feature))
+      else:
+        log.info(u"No feature flag defined for {feature}".format(feature=feature))
+
+    return False
 
 
 def is_active(feature):

From 8a4295876a4e1059f46f8fadaa1562062bfe877e Mon Sep 17 00:00:00 2001
From: Iuri de Silvio <iurisilvio@gmail.com>
Date: Wed, 30 Jul 2014 17:11:35 -0300
Subject: [PATCH 2/2] Fix test to support NoFeatureFlagFound.

---
 tests/test_edge_cases.py | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/tests/test_edge_cases.py b/tests/test_edge_cases.py
index 33a18c7..5a0da97 100644
--- a/tests/test_edge_cases.py
+++ b/tests/test_edge_cases.py
@@ -36,4 +36,5 @@ def test_running_default_handler_on_app_that_was_never_set_up_returns_false(self
     test_app = Flask(__name__)
 
     with test_app.test_request_context("/"):
-      self.assertFalse(feature_flags.AppConfigFlagHandler("BOGUS_FEATURE_FLAG"))
+      self.assertRaises(feature_flags.NoFeatureFlagFound,
+                        feature_flags.AppConfigFlagHandler, "BOGUS_FEATURE_FLAG")