allow removing items or sources from config

confuse/core.py

@@ -87,6 +87,11 @@ def add(self, value):
         """
         raise NotImplementedError
 
+    def remove(self, value):
+        """Remove source or value from config
+        """
+        raise NotImplementedError
+
     def set(self, value):
         """*Override* the value for this configuration view. The
         specified value is added as the highest-priority configuration
@@ -136,6 +141,11 @@ def __setitem__(self, key, value):
         """
         self.set({key: value})
 
+    def __delitem__(self, key):
+        """Remove value from config by key.
+        """
+        self.remove(key)
+
     def __contains__(self, key):
         return self[key].exists()
 
@@ -439,6 +449,22 @@ def __init__(self, sources):
     def add(self, obj):
         self.sources.append(ConfigSource.of(obj))
 
+    def remove(self, obj):
+        """Remove source or item from configuration
+        """
+        if isinstance(obj, ConfigSource):
+            if obj.default:
+                raise ConfigError(u'Cannot remove default source')
+            self.sources.remove(obj)
+        elif isinstance(obj, util.STRING):
+            for source in self.sources:
+                if isinstance(source, ConfigSource) and obj in source:
+                    del source[obj]
+        else:
+            raise ConfigError(u'Unrecognized obj {0}'.format(
+                obj
+            ))
+
     def set(self, value):
         self.sources.insert(0, ConfigSource.of(value))
 

test/test_views.py

@@ -241,6 +241,23 @@ def test_override_list_index(self):
         self.assertEqual(config['foo'][1].get(), 'bar')
 
 
+class DeleteTest(unittest.TestCase):
+
+    def test_remove(self):
+        config = _root({'foo': 'bar', 'qux': 'baz'})
+        config.remove('foo')
+        with self.assertRaises(confuse.NotFoundError):
+            config['foo'].get()
+        self.assertEqual(set(config.keys()), set(['qux']))
+
+    def test_del(self):
+        config = _root({'foo': 'bar', 'qux': 'baz'})
+        del config['foo']
+        with self.assertRaises(confuse.NotFoundError):
+            config['foo'].get()
+        self.assertEqual(set(config.keys()), set(['qux']))
+
+
 class BuildNamespaceDictTests(unittest.TestCase):
     def test_pure_dicts(self):
         config = {'foo': {'bar': 1}}