Be explicit about requiring keyword arguments

jstasiak · jstasiak · commit fd4ee3333e9d · 2013-09-02T00:55:26.000+01:00
diff --git a/injector.py b/injector.py
@@ -814,8 +814,13 @@ def class_wrapper(cls):
 
         @inject(**bindings)
         def init(self, *args, **kwargs):
-            for key in original_keys:
-                setattr(self, key, kwargs.pop(key.lstrip('_')))
+            try:
+                for key in original_keys:
+                    normalized_key = key.lstrip('_')
+                    setattr(self, key, kwargs.pop(normalized_key))
+            except KeyError as e:
+                reraise(e, CallError('Keyword argument %s not found' % normalized_key))
+
             orig_init(self, *args, **kwargs)
         cls.__init__ = init
         return cls
diff --git a/injector_test.py b/injector_test.py
@@ -987,6 +987,17 @@ class X(object):
         x = X(b=314)
         assert (x._b == 314)
 
+    def test_correct_exception_is_raised_when_argument_is_missing(self):
+        @inject(s=str)
+        class X(object):
+            pass
+
+        with pytest.raises(CallError):
+            self.B()
+
+        with pytest.raises(CallError):
+            self.B('something')
+
 
 def test_provides_and_scope_decorator_collaboration():
     @provides(int)
