refactor!: sqlalchemy database models

src/arcaea_offline/database/models/v4/common.py

@@ -0,0 +1,36 @@
+# pylint: disable=too-few-public-methods
+
+from sqlalchemy.orm import DeclarativeBase
+from sqlalchemy.orm.exc import DetachedInstanceError
+
+
+class ReprHelper:
+    # pylint: disable=no-member
+
+    def _repr(self, **kwargs) -> str:
+        """
+        Helper for __repr__
+
+        https://stackoverflow.com/a/55749579/16484891
+
+        CC BY-SA 4.0
+        """
+        field_strings = []
+        at_least_one_attached_attribute = False
+        for key, field in kwargs.items():
+            try:
+                field_strings.append(f"{key}={field!r}")
+            except DetachedInstanceError:
+                field_strings.append(f"{key}=DetachedInstanceError")
+            else:
+                at_least_one_attached_attribute = True
+        if at_least_one_attached_attribute:
+            return f"<{self.__class__.__name__}({','.join(field_strings)})>"
+        return f"<{self.__class__.__name__} {id(self)}>"
+
+    def __repr__(self):
+        if isinstance(self, DeclarativeBase):
+            return self._repr(
+                **{c.key: getattr(self, c.key) for c in self.__table__.columns}
+            )
+        return super().__repr__()