Fix #550

docs/main/changelog.rst

@@ -21,6 +21,10 @@ Development version
   ``FactoryAggregate.factories`` attribute.
 - Add ``.set_providers()`` method to the ``FactoryAggregate`` provider. It is an alias for
   ``FactoryAggregate.set_factories()`` method.
+- Fix ``Dependency`` provider to don't raise "Dependency is not defined" error when the ``default``
+  is a falsy value of proper type.
+  See issue `#550 <https://github.com/ets-labs/python-dependency-injector/issues/550>`_. Thanks to
+  `@approxit <https://github.com/approxit>`_ for reporting the issue.
 - Refactor ``FactoryAggregate`` provider internals.
 - Update logo on Github and in docs to support dark themes and remove some imperfections.
 

src/dependency_injector/providers.c

@@ -19881,7 +19881,7 @@ static PyObject *__pyx_pf_19dependency_injector_9providers_10Dependency_7default
  * 
  *     def set_default(self, default):             # <<<<<<<<<<<<<<
  *         """Set type."""
- *         if default and not isinstance(default, Provider):
+ *         if default is not None and not isinstance(default, Provider):
  */
 
 /* Python wrapper */
@@ -19914,25 +19914,26 @@ static PyObject *__pyx_pf_19dependency_injector_9providers_10Dependency_14set_de
   /* "dependency_injector/providers.pyx":882
  *     def set_default(self, default):
  *         """Set type."""
- *         if default and not isinstance(default, Provider):             # <<<<<<<<<<<<<<
+ *         if default is not None and not isinstance(default, Provider):             # <<<<<<<<<<<<<<
  *             default = Object(default)
  *         self.__default = default
  */
-  __pyx_t_2 = __Pyx_PyObject_IsTrue(__pyx_v_default); if (unlikely(__pyx_t_2 < 0)) __PYX_ERR(1, 882, __pyx_L1_error)
-  if (__pyx_t_2) {
+  __pyx_t_2 = (__pyx_v_default != Py_None);
+  __pyx_t_3 = (__pyx_t_2 != 0);
+  if (__pyx_t_3) {
   } else {
-    __pyx_t_1 = __pyx_t_2;
+    __pyx_t_1 = __pyx_t_3;
     goto __pyx_L4_bool_binop_done;
   }
-  __pyx_t_2 = __Pyx_TypeCheck(__pyx_v_default, __pyx_ptype_19dependency_injector_9providers_Provider); 
-  __pyx_t_3 = ((!(__pyx_t_2 != 0)) != 0);
-  __pyx_t_1 = __pyx_t_3;
+  __pyx_t_3 = __Pyx_TypeCheck(__pyx_v_default, __pyx_ptype_19dependency_injector_9providers_Provider); 
+  __pyx_t_2 = ((!(__pyx_t_3 != 0)) != 0);
+  __pyx_t_1 = __pyx_t_2;
   __pyx_L4_bool_binop_done:;
   if (__pyx_t_1) {
 
     /* "dependency_injector/providers.pyx":883
  *         """Set type."""
- *         if default and not isinstance(default, Provider):
+ *         if default is not None and not isinstance(default, Provider):
  *             default = Object(default)             # <<<<<<<<<<<<<<
  *         self.__default = default
  *         return self
@@ -19945,14 +19946,14 @@ static PyObject *__pyx_pf_19dependency_injector_9providers_10Dependency_14set_de
     /* "dependency_injector/providers.pyx":882
  *     def set_default(self, default):
  *         """Set type."""
- *         if default and not isinstance(default, Provider):             # <<<<<<<<<<<<<<
+ *         if default is not None and not isinstance(default, Provider):             # <<<<<<<<<<<<<<
  *             default = Object(default)
  *         self.__default = default
  */
   }
 
   /* "dependency_injector/providers.pyx":884
- *         if default and not isinstance(default, Provider):
+ *         if default is not None and not isinstance(default, Provider):
  *             default = Object(default)
  *         self.__default = default             # <<<<<<<<<<<<<<
  *         return self
@@ -19981,7 +19982,7 @@ static PyObject *__pyx_pf_19dependency_injector_9providers_10Dependency_14set_de
  * 
  *     def set_default(self, default):             # <<<<<<<<<<<<<<
  *         """Set type."""
- *         if default and not isinstance(default, Provider):
+ *         if default is not None and not isinstance(default, Provider):
  */
 
   /* function exit code */

src/dependency_injector/providers.pyx

@@ -879,7 +879,7 @@ cdef class Dependency(Provider):
 
     def set_default(self, default):
         """Set type."""
-        if default and not isinstance(default, Provider):
+        if default is not None and not isinstance(default, Provider):
             default = Object(default)
         self.__default = default
         return self

tests/unit/providers/test_dependency_py2_py3.py

@@ -77,6 +77,22 @@ def test_default_attribute_provider():
     assert provider.default is default
 
 
+def test_default_with_empty_dict():
+    # See: https://github.com/ets-labs/python-dependency-injector/issues/550
+    default = {}
+    provider = providers.Dependency(instance_of=dict, default=default)
+    assert provider() == default
+    assert provider.default() == default
+
+
+def test_default_with_empty_string():
+    # See: https://github.com/ets-labs/python-dependency-injector/issues/550
+    default = ""
+    provider = providers.Dependency(instance_of=str, default=default)
+    assert provider() == default
+    assert provider.default() == default
+
+
 def test_is_defined(provider):
     assert provider.is_defined is False