API: add snapshot.match_object() (#4)

thrau · web-flow · commit b0cd665e7be2 · 2024-04-25T00:20:26.000+02:00
diff --git a/localstack_snapshot/snapshots/prototype.py b/localstack_snapshot/snapshots/prototype.py
@@ -164,6 +164,23 @@ def _load_state(self) -> dict:
     def _update(self, key: str, obj_state: dict) -> None:
         self.observed_state[key] = obj_state
 
+    def match_object(self, key: str, obj: object) -> None:
+        def _convert_object_to_dict(obj_):
+            if isinstance(obj_, dict):
+                for key in list(obj_.keys()):
+                    if key.startswith("_"):
+                        del obj_[key]
+                    else:
+                        obj_[key] = _convert_object_to_dict(obj_[key])
+            elif isinstance(obj_, list):
+                for idx, val in enumerate(obj_):
+                    obj_[idx] = _convert_object_to_dict(val)
+            elif hasattr(obj_, "__dict__"):
+                return _convert_object_to_dict(obj_.__dict__)
+            return obj_
+
+        return self.match(key, _convert_object_to_dict(obj))
+
     def match(self, key: str, obj: dict) -> None:
         if key in self.called_keys:
             raise Exception(
diff --git a/tests/test_snapshots.py b/tests/test_snapshots.py
@@ -37,6 +37,48 @@ def test_context_replacement(self):
         sm.match("key_a", {"aaa": "something", "bbb": "something hello"})
         sm._assert_all()
 
+    def test_match_object_nochange(self):
+        class CustomObject:
+            def __init__(self, name, nested=False):
+                self.name = name
+                if nested:
+                    self.nested = CustomObject(f"nested{name}")
+                    self.listed = [CustomObject(f"listed{name}"), "otherobj"]
+
+        sm = SnapshotSession(scope_key="A", verify=True, base_file_path="", update=False)
+        sm.recorded_state = {
+            "key_a": {
+                "name": "myname",
+                "nested": {"name": "nestedmyname"},
+                "listed": [{"name": "listedmyname"}, "otherobj"],
+            }
+        }
+        sm.match_object("key_a", CustomObject(name="myname", nested=True))
+        sm._assert_all()
+
+    def test_match_object_ignore_private_values(self):
+        class CustomObject:
+            def __init__(self, name):
+                self.name = name
+                self._internal = "n/a"
+
+        sm = SnapshotSession(scope_key="A", verify=True, base_file_path="", update=False)
+        sm.recorded_state = {"key_a": {"name": "myname"}}
+        sm.match_object("key_a", CustomObject(name="myname"))
+        sm._assert_all()
+
+    def test_match_object_change(self):
+        class CustomObject:
+            def __init__(self, name):
+                self.name = name
+
+        sm = SnapshotSession(scope_key="A", verify=True, base_file_path="", update=False)
+        sm.recorded_state = {"key_a": {"name": "myname"}}
+        sm.match_object("key_a", CustomObject(name="diffname"))
+        with pytest.raises(Exception) as ctx:
+            sm._assert_all()
+        ctx.match("Parity snapshot failed")
+
     # def test_context_replacement_no_change(self):
     #     sm = SnapshotSession(scope_key="A", verify=True, base_file_path="", update=False)
     #     sm.add_transformer(TransformerUtility.key_value("name"))
