[Feature] Support shallow copy for Config (#1796)

* Add .owners.yml to mark daily issue shift

* Update .owners.yml

fix end of file

* Add __copy__() to Config

* fix format in config.py

* fix format in test_copy

* fix format in config.py

* Update config.py

* Update tests/test_utils/test_config.py
Co-authored-by: Zaida Zhou <58739961+zhouzaida@users.noreply.github.com>
Co-authored-by: Zaida Zhou <58739961+zhouzaida@users.noreply.github.com>

mmcv/utils/config.py

@@ -528,6 +528,13 @@ class Config:
     def __getstate__(self):
         return (self._cfg_dict, self._filename, self._text)
 
+    def __copy__(self):
+        cls = self.__class__
+        other = cls.__new__(cls)
+        other.__dict__.update(self.__dict__)
+
+        return other
+
     def __deepcopy__(self, memo):
         cls = self.__class__
         other = cls.__new__(cls)

tests/test_utils/test_config.py

@@ -549,3 +549,15 @@ def test_deepcopy():
     assert new_cfg._cfg_dict is not cfg._cfg_dict
     assert new_cfg._filename == cfg._filename
     assert new_cfg._text == cfg._text
+
+
+def test_copy():
+    cfg_file = osp.join(data_path, 'config/n.py')
+    cfg = Config.fromfile(cfg_file)
+    new_cfg = copy.copy(cfg)
+
+    assert isinstance(new_cfg, Config)
+    assert new_cfg is not cfg
+    assert new_cfg._cfg_dict is cfg._cfg_dict
+    assert new_cfg._filename == cfg._filename
+    assert new_cfg._text == cfg._text