Merge pull request #158 from partizaans/fix/refresh-from-db

Update the initial state after calling `refresh_from_db` on the model instance

Author: EnriqueSoria

django_lifecycle/mixins.py

@@ -212,6 +212,10 @@ def delete(self, *args, **kwargs):
         self._run_hooked_methods(AFTER_DELETE, **kwargs)
         return value
 
+    def refresh_from_db(self, *args, **kwargs):
+        super().refresh_from_db(*args, **kwargs)
+        self._initial_state = self._snapshot_state()
+
     @classmethod
     @lru_cache(typed=True)
     def _potentially_hooked_methods(cls):

docs/advanced.md

@@ -4,10 +4,10 @@
 
 These are available on your model instance when the mixin or extend the base model is used.
 
-|                  Method                  |                                              Details                                              |
-|:----------------------------------------:|:-------------------------------------------------------------------------------------------------:|
-|  `has_changed(field_name: str) -> bool`  | Return a boolean indicating whether the field's value has changed since the model was initialized |
-| `initial_value(field_name: str) -> bool` |                Return the value of the field when the model was first initialized                 |
+|                  Method                  |                                                         Details                                                         |
+|:----------------------------------------:|:-----------------------------------------------------------------------------------------------------------------------:|
+|  `has_changed(field_name: str) -> bool`  | Return a boolean indicating whether the field's value has changed since the model was initialized, or refreshed from db |
+| `initial_value(field_name: str) -> bool` |                Return the value of the field when the model was first initialized, or refreshed from db                 |
 
 ### Example
 You can use these methods for more advanced checks, for example:

tests/testapp/tests/test_mixin.py

@@ -203,6 +203,17 @@ def test_has_changed(self):
         user_account.username = "Josephine"
         self.assertTrue(user_account.has_changed("username"))
 
+    def test_has_changed_when_refreshed_from_db(self):
+        data = self.stub_data
+        UserAccount.objects.create(**data)
+        user_account = UserAccount.objects.get()
+        UserAccount.objects.update(username="not " + user_account.username)
+        user_account.refresh_from_db()
+        user_account.username = data["username"]
+        self.assertTrue(user_account.has_changed("username"),
+                        'The initial state should get updated after refreshing the object from db')
+
+
     def test_has_changed_is_true_if_fk_related_model_field_has_changed(self):
         org = Organization.objects.create(name="Dunder Mifflin")
         UserAccount.objects.create(**self.stub_data, organization=org)