Keeps track of the options sent to :paramref:`.relationship.cascade`
| 178 | |
| 179 | |
| 180 | class CascadeOptions(FrozenSet[str]): |
| 181 | """Keeps track of the options sent to |
| 182 | :paramref:`.relationship.cascade`""" |
| 183 | |
| 184 | _add_w_all_cascades = all_cascades.difference( |
| 185 | ["all", "none", "delete-orphan"] |
| 186 | ) |
| 187 | _allowed_cascades = all_cascades |
| 188 | |
| 189 | _viewonly_cascades = ["expunge", "all", "none", "refresh-expire", "merge"] |
| 190 | |
| 191 | __slots__ = ( |
| 192 | "save_update", |
| 193 | "delete", |
| 194 | "refresh_expire", |
| 195 | "merge", |
| 196 | "expunge", |
| 197 | "delete_orphan", |
| 198 | ) |
| 199 | |
| 200 | save_update: bool |
| 201 | delete: bool |
| 202 | refresh_expire: bool |
| 203 | merge: bool |
| 204 | expunge: bool |
| 205 | delete_orphan: bool |
| 206 | |
| 207 | def __new__( |
| 208 | cls, value_list: Optional[Union[Iterable[str], str]] |
| 209 | ) -> CascadeOptions: |
| 210 | if isinstance(value_list, str) or value_list is None: |
| 211 | return cls.from_string(value_list) # type: ignore |
| 212 | values = set(value_list) |
| 213 | if values.difference(cls._allowed_cascades): |
| 214 | raise sa_exc.ArgumentError( |
| 215 | "Invalid cascade option(s): %s" |
| 216 | % ", ".join( |
| 217 | [ |
| 218 | repr(x) |
| 219 | for x in sorted( |
| 220 | values.difference(cls._allowed_cascades) |
| 221 | ) |
| 222 | ] |
| 223 | ) |
| 224 | ) |
| 225 | |
| 226 | if "all" in values: |
| 227 | values.update(cls._add_w_all_cascades) |
| 228 | if "none" in values: |
| 229 | values.clear() |
| 230 | values.discard("all") |
| 231 | |
| 232 | self = super().__new__(cls, values) |
| 233 | self.save_update = "save-update" in values |
| 234 | self.delete = "delete" in values |
| 235 | self.refresh_expire = "refresh-expire" in values |
| 236 | self.merge = "merge" in values |
| 237 | self.expunge = "expunge" in values |