(self)
| 336 | return ret, klass_info, annotations |
| 337 | |
| 338 | def _order_by_pairs(self): |
| 339 | if self.query.extra_order_by: |
| 340 | ordering = self.query.extra_order_by |
| 341 | elif not self.query.default_ordering: |
| 342 | ordering = self.query.order_by |
| 343 | elif self.query.order_by: |
| 344 | ordering = self.query.order_by |
| 345 | elif (meta := self.query.get_meta()) and meta.ordering: |
| 346 | ordering = meta.ordering |
| 347 | self._meta_ordering = ordering |
| 348 | else: |
| 349 | ordering = [] |
| 350 | if self.query.standard_ordering: |
| 351 | default_order, _ = ORDER_DIR["ASC"] |
| 352 | else: |
| 353 | default_order, _ = ORDER_DIR["DESC"] |
| 354 | |
| 355 | selected_exprs = {} |
| 356 | # Avoid computing `selected_exprs` if there is no `ordering` as it's |
| 357 | # relatively expensive. |
| 358 | if ordering and (select := self.select): |
| 359 | for ordinal, (expr, _, alias) in enumerate(select, start=1): |
| 360 | pos_expr = PositionRef(ordinal, alias, expr) |
| 361 | if alias: |
| 362 | selected_exprs[alias] = pos_expr |
| 363 | selected_exprs[expr] = pos_expr |
| 364 | |
| 365 | for field in ordering: |
| 366 | if hasattr(field, "resolve_expression"): |
| 367 | if isinstance(field, Value): |
| 368 | # output_field must be resolved for constants. |
| 369 | field = Cast(field, field.output_field) |
| 370 | if not isinstance(field, OrderBy): |
| 371 | field = field.asc() |
| 372 | if not self.query.standard_ordering: |
| 373 | field = field.copy() |
| 374 | field.reverse_ordering() |
| 375 | select_ref = selected_exprs.get(field.expression) |
| 376 | if select_ref or ( |
| 377 | isinstance(field.expression, F) |
| 378 | and (select_ref := selected_exprs.get(field.expression.name)) |
| 379 | ): |
| 380 | # Emulation of NULLS (FIRST|LAST) cannot be combined with |
| 381 | # the usage of ordering by position. |
| 382 | if ( |
| 383 | field.nulls_first is None and field.nulls_last is None |
| 384 | ) or self.connection.features.supports_order_by_nulls_modifier: |
| 385 | field = field.copy() |
| 386 | field.expression = select_ref |
| 387 | # Alias collisions are not possible when dealing with |
| 388 | # combined queries so fallback to it if emulation of NULLS |
| 389 | # handling is required. |
| 390 | elif self.query.combinator: |
| 391 | field = field.copy() |
| 392 | field.expression = Ref(select_ref.refs, select_ref.source) |
| 393 | yield field, select_ref is not None |
| 394 | continue |
| 395 | if field == "?": # random |
no test coverage detected