coercions.py 40 KB

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  1. # sql/coercions.py
  2. # Copyright (C) 2005-2025 the SQLAlchemy authors and contributors
  3. # <see AUTHORS file>
  4. #
  5. # This module is part of SQLAlchemy and is released under
  6. # the MIT License: https://www.opensource.org/licenses/mit-license.php
  7. # mypy: allow-untyped-defs, allow-untyped-calls
  8. from __future__ import annotations
  9. import collections.abc as collections_abc
  10. import numbers
  11. import re
  12. import typing
  13. from typing import Any
  14. from typing import Callable
  15. from typing import cast
  16. from typing import Dict
  17. from typing import Iterable
  18. from typing import Iterator
  19. from typing import List
  20. from typing import NoReturn
  21. from typing import Optional
  22. from typing import overload
  23. from typing import Sequence
  24. from typing import Tuple
  25. from typing import Type
  26. from typing import TYPE_CHECKING
  27. from typing import TypeVar
  28. from typing import Union
  29. from . import roles
  30. from . import visitors
  31. from ._typing import is_from_clause
  32. from .base import ExecutableOption
  33. from .base import Options
  34. from .cache_key import HasCacheKey
  35. from .visitors import Visitable
  36. from .. import exc
  37. from .. import inspection
  38. from .. import util
  39. from ..util.typing import Literal
  40. if typing.TYPE_CHECKING:
  41. # elements lambdas schema selectable are set by __init__
  42. from . import elements
  43. from . import lambdas
  44. from . import schema
  45. from . import selectable
  46. from ._typing import _ColumnExpressionArgument
  47. from ._typing import _ColumnsClauseArgument
  48. from ._typing import _DDLColumnArgument
  49. from ._typing import _DMLTableArgument
  50. from ._typing import _FromClauseArgument
  51. from .dml import _DMLTableElement
  52. from .elements import BindParameter
  53. from .elements import ClauseElement
  54. from .elements import ColumnClause
  55. from .elements import ColumnElement
  56. from .elements import NamedColumn
  57. from .elements import SQLCoreOperations
  58. from .elements import TextClause
  59. from .schema import Column
  60. from .selectable import _ColumnsClauseElement
  61. from .selectable import _JoinTargetProtocol
  62. from .selectable import FromClause
  63. from .selectable import HasCTE
  64. from .selectable import SelectBase
  65. from .selectable import Subquery
  66. from .visitors import _TraverseCallableType
  67. _SR = TypeVar("_SR", bound=roles.SQLRole)
  68. _F = TypeVar("_F", bound=Callable[..., Any])
  69. _StringOnlyR = TypeVar("_StringOnlyR", bound=roles.StringRole)
  70. _T = TypeVar("_T", bound=Any)
  71. def _is_literal(element: Any) -> bool:
  72. """Return whether or not the element is a "literal" in the context
  73. of a SQL expression construct.
  74. """
  75. return not isinstance(
  76. element,
  77. (Visitable, schema.SchemaEventTarget),
  78. ) and not hasattr(element, "__clause_element__")
  79. def _deep_is_literal(element):
  80. """Return whether or not the element is a "literal" in the context
  81. of a SQL expression construct.
  82. does a deeper more esoteric check than _is_literal. is used
  83. for lambda elements that have to distinguish values that would
  84. be bound vs. not without any context.
  85. """
  86. if isinstance(element, collections_abc.Sequence) and not isinstance(
  87. element, str
  88. ):
  89. for elem in element:
  90. if not _deep_is_literal(elem):
  91. return False
  92. else:
  93. return True
  94. return (
  95. not isinstance(
  96. element,
  97. (
  98. Visitable,
  99. schema.SchemaEventTarget,
  100. HasCacheKey,
  101. Options,
  102. util.langhelpers.symbol,
  103. ),
  104. )
  105. and not hasattr(element, "__clause_element__")
  106. and (
  107. not isinstance(element, type)
  108. or not issubclass(element, HasCacheKey)
  109. )
  110. )
  111. def _document_text_coercion(
  112. paramname: str, meth_rst: str, param_rst: str
  113. ) -> Callable[[_F], _F]:
  114. return util.add_parameter_text(
  115. paramname,
  116. (
  117. ".. warning:: "
  118. "The %s argument to %s can be passed as a Python string argument, "
  119. "which will be treated "
  120. "as **trusted SQL text** and rendered as given. **DO NOT PASS "
  121. "UNTRUSTED INPUT TO THIS PARAMETER**."
  122. )
  123. % (param_rst, meth_rst),
  124. )
  125. def _expression_collection_was_a_list(
  126. attrname: str,
  127. fnname: str,
  128. args: Union[Sequence[_T], Sequence[Sequence[_T]]],
  129. ) -> Sequence[_T]:
  130. if args and isinstance(args[0], (list, set, dict)) and len(args) == 1:
  131. if isinstance(args[0], list):
  132. raise exc.ArgumentError(
  133. f'The "{attrname}" argument to {fnname}(), when '
  134. "referring to a sequence "
  135. "of items, is now passed as a series of positional "
  136. "elements, rather than as a list. "
  137. )
  138. return cast("Sequence[_T]", args[0])
  139. return cast("Sequence[_T]", args)
  140. @overload
  141. def expect(
  142. role: Type[roles.TruncatedLabelRole],
  143. element: Any,
  144. **kw: Any,
  145. ) -> str: ...
  146. @overload
  147. def expect(
  148. role: Type[roles.DMLColumnRole],
  149. element: Any,
  150. *,
  151. as_key: Literal[True] = ...,
  152. **kw: Any,
  153. ) -> str: ...
  154. @overload
  155. def expect(
  156. role: Type[roles.LiteralValueRole],
  157. element: Any,
  158. **kw: Any,
  159. ) -> BindParameter[Any]: ...
  160. @overload
  161. def expect(
  162. role: Type[roles.DDLReferredColumnRole],
  163. element: Any,
  164. **kw: Any,
  165. ) -> Union[Column[Any], str]: ...
  166. @overload
  167. def expect(
  168. role: Type[roles.DDLConstraintColumnRole],
  169. element: Any,
  170. **kw: Any,
  171. ) -> Union[Column[Any], str]: ...
  172. @overload
  173. def expect(
  174. role: Type[roles.StatementOptionRole],
  175. element: Any,
  176. **kw: Any,
  177. ) -> Union[ColumnElement[Any], TextClause]: ...
  178. @overload
  179. def expect(
  180. role: Type[roles.LabeledColumnExprRole[Any]],
  181. element: _ColumnExpressionArgument[_T],
  182. **kw: Any,
  183. ) -> NamedColumn[_T]: ...
  184. @overload
  185. def expect(
  186. role: Union[
  187. Type[roles.ExpressionElementRole[Any]],
  188. Type[roles.LimitOffsetRole],
  189. Type[roles.WhereHavingRole],
  190. ],
  191. element: _ColumnExpressionArgument[_T],
  192. **kw: Any,
  193. ) -> ColumnElement[_T]: ...
  194. @overload
  195. def expect(
  196. role: Union[
  197. Type[roles.ExpressionElementRole[Any]],
  198. Type[roles.LimitOffsetRole],
  199. Type[roles.WhereHavingRole],
  200. Type[roles.OnClauseRole],
  201. Type[roles.ColumnArgumentRole],
  202. ],
  203. element: Any,
  204. **kw: Any,
  205. ) -> ColumnElement[Any]: ...
  206. @overload
  207. def expect(
  208. role: Type[roles.DMLTableRole],
  209. element: _DMLTableArgument,
  210. **kw: Any,
  211. ) -> _DMLTableElement: ...
  212. @overload
  213. def expect(
  214. role: Type[roles.HasCTERole],
  215. element: HasCTE,
  216. **kw: Any,
  217. ) -> HasCTE: ...
  218. @overload
  219. def expect(
  220. role: Type[roles.SelectStatementRole],
  221. element: SelectBase,
  222. **kw: Any,
  223. ) -> SelectBase: ...
  224. @overload
  225. def expect(
  226. role: Type[roles.FromClauseRole],
  227. element: _FromClauseArgument,
  228. **kw: Any,
  229. ) -> FromClause: ...
  230. @overload
  231. def expect(
  232. role: Type[roles.FromClauseRole],
  233. element: SelectBase,
  234. *,
  235. explicit_subquery: Literal[True] = ...,
  236. **kw: Any,
  237. ) -> Subquery: ...
  238. @overload
  239. def expect(
  240. role: Type[roles.ColumnsClauseRole],
  241. element: _ColumnsClauseArgument[Any],
  242. **kw: Any,
  243. ) -> _ColumnsClauseElement: ...
  244. @overload
  245. def expect(
  246. role: Type[roles.JoinTargetRole],
  247. element: _JoinTargetProtocol,
  248. **kw: Any,
  249. ) -> _JoinTargetProtocol: ...
  250. # catchall for not-yet-implemented overloads
  251. @overload
  252. def expect(
  253. role: Type[_SR],
  254. element: Any,
  255. **kw: Any,
  256. ) -> Any: ...
  257. def expect(
  258. role: Type[_SR],
  259. element: Any,
  260. *,
  261. apply_propagate_attrs: Optional[ClauseElement] = None,
  262. argname: Optional[str] = None,
  263. post_inspect: bool = False,
  264. disable_inspection: bool = False,
  265. **kw: Any,
  266. ) -> Any:
  267. if (
  268. role.allows_lambda
  269. # note callable() will not invoke a __getattr__() method, whereas
  270. # hasattr(obj, "__call__") will. by keeping the callable() check here
  271. # we prevent most needless calls to hasattr() and therefore
  272. # __getattr__(), which is present on ColumnElement.
  273. and callable(element)
  274. and hasattr(element, "__code__")
  275. ):
  276. return lambdas.LambdaElement(
  277. element,
  278. role,
  279. lambdas.LambdaOptions(**kw),
  280. apply_propagate_attrs=apply_propagate_attrs,
  281. )
  282. # major case is that we are given a ClauseElement already, skip more
  283. # elaborate logic up front if possible
  284. impl = _impl_lookup[role]
  285. original_element = element
  286. if not isinstance(
  287. element,
  288. (
  289. elements.CompilerElement,
  290. schema.SchemaItem,
  291. schema.FetchedValue,
  292. lambdas.PyWrapper,
  293. ),
  294. ):
  295. resolved = None
  296. if impl._resolve_literal_only:
  297. resolved = impl._literal_coercion(element, **kw)
  298. else:
  299. original_element = element
  300. is_clause_element = False
  301. # this is a special performance optimization for ORM
  302. # joins used by JoinTargetImpl that we don't go through the
  303. # work of creating __clause_element__() when we only need the
  304. # original QueryableAttribute, as the former will do clause
  305. # adaption and all that which is just thrown away here.
  306. if (
  307. impl._skip_clauseelement_for_target_match
  308. and isinstance(element, role)
  309. and hasattr(element, "__clause_element__")
  310. ):
  311. is_clause_element = True
  312. else:
  313. while hasattr(element, "__clause_element__"):
  314. is_clause_element = True
  315. if not getattr(element, "is_clause_element", False):
  316. element = element.__clause_element__()
  317. else:
  318. break
  319. if not is_clause_element:
  320. if impl._use_inspection and not disable_inspection:
  321. insp = inspection.inspect(element, raiseerr=False)
  322. if insp is not None:
  323. if post_inspect:
  324. insp._post_inspect
  325. try:
  326. resolved = insp.__clause_element__()
  327. except AttributeError:
  328. impl._raise_for_expected(original_element, argname)
  329. if resolved is None:
  330. resolved = impl._literal_coercion(
  331. element, argname=argname, **kw
  332. )
  333. else:
  334. resolved = element
  335. elif isinstance(element, lambdas.PyWrapper):
  336. resolved = element._sa__py_wrapper_literal(**kw)
  337. else:
  338. resolved = element
  339. if apply_propagate_attrs is not None:
  340. if typing.TYPE_CHECKING:
  341. assert isinstance(resolved, (SQLCoreOperations, ClauseElement))
  342. if not apply_propagate_attrs._propagate_attrs and getattr(
  343. resolved, "_propagate_attrs", None
  344. ):
  345. apply_propagate_attrs._propagate_attrs = resolved._propagate_attrs
  346. if impl._role_class in resolved.__class__.__mro__:
  347. if impl._post_coercion:
  348. resolved = impl._post_coercion(
  349. resolved,
  350. argname=argname,
  351. original_element=original_element,
  352. **kw,
  353. )
  354. return resolved
  355. else:
  356. return impl._implicit_coercions(
  357. original_element, resolved, argname=argname, **kw
  358. )
  359. def expect_as_key(
  360. role: Type[roles.DMLColumnRole], element: Any, **kw: Any
  361. ) -> str:
  362. kw.pop("as_key", None)
  363. return expect(role, element, as_key=True, **kw)
  364. def expect_col_expression_collection(
  365. role: Type[roles.DDLConstraintColumnRole],
  366. expressions: Iterable[_DDLColumnArgument],
  367. ) -> Iterator[
  368. Tuple[
  369. Union[str, Column[Any]],
  370. Optional[ColumnClause[Any]],
  371. Optional[str],
  372. Optional[Union[Column[Any], str]],
  373. ]
  374. ]:
  375. for expr in expressions:
  376. strname = None
  377. column = None
  378. resolved: Union[Column[Any], str] = expect(role, expr)
  379. if isinstance(resolved, str):
  380. assert isinstance(expr, str)
  381. strname = resolved = expr
  382. else:
  383. cols: List[Column[Any]] = []
  384. col_append: _TraverseCallableType[Column[Any]] = cols.append
  385. visitors.traverse(resolved, {}, {"column": col_append})
  386. if cols:
  387. column = cols[0]
  388. add_element = column if column is not None else strname
  389. yield resolved, column, strname, add_element
  390. class RoleImpl:
  391. __slots__ = ("_role_class", "name", "_use_inspection")
  392. def _literal_coercion(self, element, **kw):
  393. raise NotImplementedError()
  394. _post_coercion: Any = None
  395. _resolve_literal_only = False
  396. _skip_clauseelement_for_target_match = False
  397. def __init__(self, role_class):
  398. self._role_class = role_class
  399. self.name = role_class._role_name
  400. self._use_inspection = issubclass(role_class, roles.UsesInspection)
  401. def _implicit_coercions(
  402. self,
  403. element: Any,
  404. resolved: Any,
  405. argname: Optional[str] = None,
  406. **kw: Any,
  407. ) -> Any:
  408. self._raise_for_expected(element, argname, resolved)
  409. def _raise_for_expected(
  410. self,
  411. element: Any,
  412. argname: Optional[str] = None,
  413. resolved: Optional[Any] = None,
  414. *,
  415. advice: Optional[str] = None,
  416. code: Optional[str] = None,
  417. err: Optional[Exception] = None,
  418. **kw: Any,
  419. ) -> NoReturn:
  420. if resolved is not None and resolved is not element:
  421. got = "%r object resolved from %r object" % (resolved, element)
  422. else:
  423. got = repr(element)
  424. if argname:
  425. msg = "%s expected for argument %r; got %s." % (
  426. self.name,
  427. argname,
  428. got,
  429. )
  430. else:
  431. msg = "%s expected, got %s." % (self.name, got)
  432. if advice:
  433. msg += " " + advice
  434. raise exc.ArgumentError(msg, code=code) from err
  435. class _Deannotate:
  436. __slots__ = ()
  437. def _post_coercion(self, resolved, **kw):
  438. from .util import _deep_deannotate
  439. return _deep_deannotate(resolved)
  440. class _StringOnly:
  441. __slots__ = ()
  442. _resolve_literal_only = True
  443. class _ReturnsStringKey(RoleImpl):
  444. __slots__ = ()
  445. def _implicit_coercions(self, element, resolved, argname=None, **kw):
  446. if isinstance(element, str):
  447. return element
  448. else:
  449. self._raise_for_expected(element, argname, resolved)
  450. def _literal_coercion(self, element, **kw):
  451. return element
  452. class _ColumnCoercions(RoleImpl):
  453. __slots__ = ()
  454. def _warn_for_scalar_subquery_coercion(self):
  455. util.warn(
  456. "implicitly coercing SELECT object to scalar subquery; "
  457. "please use the .scalar_subquery() method to produce a scalar "
  458. "subquery.",
  459. )
  460. def _implicit_coercions(self, element, resolved, argname=None, **kw):
  461. original_element = element
  462. if not getattr(resolved, "is_clause_element", False):
  463. self._raise_for_expected(original_element, argname, resolved)
  464. elif resolved._is_select_base:
  465. self._warn_for_scalar_subquery_coercion()
  466. return resolved.scalar_subquery()
  467. elif resolved._is_from_clause and isinstance(
  468. resolved, selectable.Subquery
  469. ):
  470. self._warn_for_scalar_subquery_coercion()
  471. return resolved.element.scalar_subquery()
  472. elif self._role_class.allows_lambda and resolved._is_lambda_element:
  473. return resolved
  474. else:
  475. self._raise_for_expected(original_element, argname, resolved)
  476. def _no_text_coercion(
  477. element: Any,
  478. argname: Optional[str] = None,
  479. exc_cls: Type[exc.SQLAlchemyError] = exc.ArgumentError,
  480. extra: Optional[str] = None,
  481. err: Optional[Exception] = None,
  482. ) -> NoReturn:
  483. raise exc_cls(
  484. "%(extra)sTextual SQL expression %(expr)r %(argname)sshould be "
  485. "explicitly declared as text(%(expr)r)"
  486. % {
  487. "expr": util.ellipses_string(element),
  488. "argname": "for argument %s" % (argname,) if argname else "",
  489. "extra": "%s " % extra if extra else "",
  490. }
  491. ) from err
  492. class _NoTextCoercion(RoleImpl):
  493. __slots__ = ()
  494. def _literal_coercion(self, element, *, argname=None, **kw):
  495. if isinstance(element, str) and issubclass(
  496. elements.TextClause, self._role_class
  497. ):
  498. _no_text_coercion(element, argname)
  499. else:
  500. self._raise_for_expected(element, argname)
  501. class _CoerceLiterals(RoleImpl):
  502. __slots__ = ()
  503. _coerce_consts = False
  504. _coerce_star = False
  505. _coerce_numerics = False
  506. def _text_coercion(self, element, argname=None):
  507. return _no_text_coercion(element, argname)
  508. def _literal_coercion(self, element, *, argname=None, **kw):
  509. if isinstance(element, str):
  510. if self._coerce_star and element == "*":
  511. return elements.ColumnClause("*", is_literal=True)
  512. else:
  513. return self._text_coercion(element, argname, **kw)
  514. if self._coerce_consts:
  515. if element is None:
  516. return elements.Null()
  517. elif element is False:
  518. return elements.False_()
  519. elif element is True:
  520. return elements.True_()
  521. if self._coerce_numerics and isinstance(element, (numbers.Number)):
  522. return elements.ColumnClause(str(element), is_literal=True)
  523. self._raise_for_expected(element, argname)
  524. class LiteralValueImpl(RoleImpl):
  525. _resolve_literal_only = True
  526. def _implicit_coercions(
  527. self,
  528. element,
  529. resolved,
  530. argname=None,
  531. *,
  532. type_=None,
  533. literal_execute=False,
  534. **kw,
  535. ):
  536. if not _is_literal(resolved):
  537. self._raise_for_expected(
  538. element, resolved=resolved, argname=argname, **kw
  539. )
  540. return elements.BindParameter(
  541. None,
  542. element,
  543. type_=type_,
  544. unique=True,
  545. literal_execute=literal_execute,
  546. )
  547. def _literal_coercion(self, element, **kw):
  548. return element
  549. class _SelectIsNotFrom(RoleImpl):
  550. __slots__ = ()
  551. def _raise_for_expected(
  552. self,
  553. element: Any,
  554. argname: Optional[str] = None,
  555. resolved: Optional[Any] = None,
  556. *,
  557. advice: Optional[str] = None,
  558. code: Optional[str] = None,
  559. err: Optional[Exception] = None,
  560. **kw: Any,
  561. ) -> NoReturn:
  562. if (
  563. not advice
  564. and isinstance(element, roles.SelectStatementRole)
  565. or isinstance(resolved, roles.SelectStatementRole)
  566. ):
  567. advice = (
  568. "To create a "
  569. "FROM clause from a %s object, use the .subquery() method."
  570. % (resolved.__class__ if resolved is not None else element,)
  571. )
  572. code = "89ve"
  573. else:
  574. code = None
  575. super()._raise_for_expected(
  576. element,
  577. argname=argname,
  578. resolved=resolved,
  579. advice=advice,
  580. code=code,
  581. err=err,
  582. **kw,
  583. )
  584. # never reached
  585. assert False
  586. class HasCacheKeyImpl(RoleImpl):
  587. __slots__ = ()
  588. def _implicit_coercions(
  589. self,
  590. element: Any,
  591. resolved: Any,
  592. argname: Optional[str] = None,
  593. **kw: Any,
  594. ) -> Any:
  595. if isinstance(element, HasCacheKey):
  596. return element
  597. else:
  598. self._raise_for_expected(element, argname, resolved)
  599. def _literal_coercion(self, element, **kw):
  600. return element
  601. class ExecutableOptionImpl(RoleImpl):
  602. __slots__ = ()
  603. def _implicit_coercions(
  604. self,
  605. element: Any,
  606. resolved: Any,
  607. argname: Optional[str] = None,
  608. **kw: Any,
  609. ) -> Any:
  610. if isinstance(element, ExecutableOption):
  611. return element
  612. else:
  613. self._raise_for_expected(element, argname, resolved)
  614. def _literal_coercion(self, element, **kw):
  615. return element
  616. class ExpressionElementImpl(_ColumnCoercions, RoleImpl):
  617. __slots__ = ()
  618. def _literal_coercion(
  619. self, element, *, name=None, type_=None, is_crud=False, **kw
  620. ):
  621. if (
  622. element is None
  623. and not is_crud
  624. and (type_ is None or not type_.should_evaluate_none)
  625. ):
  626. # TODO: there's no test coverage now for the
  627. # "should_evaluate_none" part of this, as outside of "crud" this
  628. # codepath is not normally used except in some special cases
  629. return elements.Null()
  630. else:
  631. try:
  632. return elements.BindParameter(
  633. name, element, type_, unique=True, _is_crud=is_crud
  634. )
  635. except exc.ArgumentError as err:
  636. self._raise_for_expected(element, err=err)
  637. def _raise_for_expected(self, element, argname=None, resolved=None, **kw):
  638. # select uses implicit coercion with warning instead of raising
  639. if isinstance(element, selectable.Values):
  640. advice = (
  641. "To create a column expression from a VALUES clause, "
  642. "use the .scalar_values() method."
  643. )
  644. elif isinstance(element, roles.AnonymizedFromClauseRole):
  645. advice = (
  646. "To create a column expression from a FROM clause row "
  647. "as a whole, use the .table_valued() method."
  648. )
  649. else:
  650. advice = None
  651. return super()._raise_for_expected(
  652. element, argname=argname, resolved=resolved, advice=advice, **kw
  653. )
  654. class BinaryElementImpl(ExpressionElementImpl, RoleImpl):
  655. __slots__ = ()
  656. def _literal_coercion( # type: ignore[override]
  657. self,
  658. element,
  659. *,
  660. expr,
  661. operator,
  662. bindparam_type=None,
  663. argname=None,
  664. **kw,
  665. ):
  666. try:
  667. return expr._bind_param(operator, element, type_=bindparam_type)
  668. except exc.ArgumentError as err:
  669. self._raise_for_expected(element, err=err)
  670. def _post_coercion(self, resolved, *, expr, bindparam_type=None, **kw):
  671. if resolved.type._isnull and not expr.type._isnull:
  672. resolved = resolved._with_binary_element_type(
  673. bindparam_type if bindparam_type is not None else expr.type
  674. )
  675. return resolved
  676. class InElementImpl(RoleImpl):
  677. __slots__ = ()
  678. def _implicit_coercions(
  679. self,
  680. element: Any,
  681. resolved: Any,
  682. argname: Optional[str] = None,
  683. **kw: Any,
  684. ) -> Any:
  685. if resolved._is_from_clause:
  686. if (
  687. isinstance(resolved, selectable.Alias)
  688. and resolved.element._is_select_base
  689. ):
  690. self._warn_for_implicit_coercion(resolved)
  691. return self._post_coercion(resolved.element, **kw)
  692. else:
  693. self._warn_for_implicit_coercion(resolved)
  694. return self._post_coercion(resolved.select(), **kw)
  695. else:
  696. self._raise_for_expected(element, argname, resolved)
  697. def _warn_for_implicit_coercion(self, elem):
  698. util.warn(
  699. "Coercing %s object into a select() for use in IN(); "
  700. "please pass a select() construct explicitly"
  701. % (elem.__class__.__name__)
  702. )
  703. @util.preload_module("sqlalchemy.sql.elements")
  704. def _literal_coercion(self, element, *, expr, operator, **kw): # type: ignore[override] # noqa: E501
  705. if util.is_non_string_iterable(element):
  706. non_literal_expressions: Dict[
  707. Optional[_ColumnExpressionArgument[Any]],
  708. _ColumnExpressionArgument[Any],
  709. ] = {}
  710. element = list(element)
  711. for o in element:
  712. if not _is_literal(o):
  713. if not isinstance(
  714. o, util.preloaded.sql_elements.ColumnElement
  715. ) and not hasattr(o, "__clause_element__"):
  716. self._raise_for_expected(element, **kw)
  717. else:
  718. non_literal_expressions[o] = o
  719. if non_literal_expressions:
  720. return elements.ClauseList(
  721. *[
  722. (
  723. non_literal_expressions[o]
  724. if o in non_literal_expressions
  725. else expr._bind_param(operator, o)
  726. )
  727. for o in element
  728. ]
  729. )
  730. else:
  731. return expr._bind_param(operator, element, expanding=True)
  732. else:
  733. self._raise_for_expected(element, **kw)
  734. def _post_coercion(self, element, *, expr, operator, **kw):
  735. if element._is_select_base:
  736. # for IN, we are doing scalar_subquery() coercion without
  737. # a warning
  738. return element.scalar_subquery()
  739. elif isinstance(element, elements.ClauseList):
  740. assert not len(element.clauses) == 0
  741. return element.self_group(against=operator)
  742. elif isinstance(element, elements.BindParameter):
  743. element = element._clone(maintain_key=True)
  744. element.expanding = True
  745. element.expand_op = operator
  746. return element
  747. elif isinstance(element, selectable.Values):
  748. return element.scalar_values()
  749. else:
  750. return element
  751. class OnClauseImpl(_ColumnCoercions, RoleImpl):
  752. __slots__ = ()
  753. _coerce_consts = True
  754. def _literal_coercion(self, element, **kw):
  755. self._raise_for_expected(element)
  756. def _post_coercion(self, resolved, *, original_element=None, **kw):
  757. # this is a hack right now as we want to use coercion on an
  758. # ORM InstrumentedAttribute, but we want to return the object
  759. # itself if it is one, not its clause element.
  760. # ORM context _join and _legacy_join() would need to be improved
  761. # to look for annotations in a clause element form.
  762. if isinstance(original_element, roles.JoinTargetRole):
  763. return original_element
  764. return resolved
  765. class WhereHavingImpl(_CoerceLiterals, _ColumnCoercions, RoleImpl):
  766. __slots__ = ()
  767. _coerce_consts = True
  768. def _text_coercion(self, element, argname=None):
  769. return _no_text_coercion(element, argname)
  770. class StatementOptionImpl(_CoerceLiterals, RoleImpl):
  771. __slots__ = ()
  772. _coerce_consts = True
  773. def _text_coercion(self, element, argname=None):
  774. return elements.TextClause(element)
  775. class ColumnArgumentImpl(_NoTextCoercion, RoleImpl):
  776. __slots__ = ()
  777. class ColumnArgumentOrKeyImpl(_ReturnsStringKey, RoleImpl):
  778. __slots__ = ()
  779. class StrAsPlainColumnImpl(_CoerceLiterals, RoleImpl):
  780. __slots__ = ()
  781. def _text_coercion(self, element, argname=None):
  782. return elements.ColumnClause(element)
  783. class ByOfImpl(_CoerceLiterals, _ColumnCoercions, RoleImpl, roles.ByOfRole):
  784. __slots__ = ()
  785. _coerce_consts = True
  786. def _text_coercion(self, element, argname=None):
  787. return elements._textual_label_reference(element)
  788. class OrderByImpl(ByOfImpl, RoleImpl):
  789. __slots__ = ()
  790. def _post_coercion(self, resolved, **kw):
  791. if (
  792. isinstance(resolved, self._role_class)
  793. and resolved._order_by_label_element is not None
  794. ):
  795. return elements._label_reference(resolved)
  796. else:
  797. return resolved
  798. class GroupByImpl(ByOfImpl, RoleImpl):
  799. __slots__ = ()
  800. def _implicit_coercions(
  801. self,
  802. element: Any,
  803. resolved: Any,
  804. argname: Optional[str] = None,
  805. **kw: Any,
  806. ) -> Any:
  807. if is_from_clause(resolved):
  808. return elements.ClauseList(*resolved.c)
  809. else:
  810. return resolved
  811. class DMLColumnImpl(_ReturnsStringKey, RoleImpl):
  812. __slots__ = ()
  813. def _post_coercion(self, element, *, as_key=False, **kw):
  814. if as_key:
  815. return element.key
  816. else:
  817. return element
  818. class ConstExprImpl(RoleImpl):
  819. __slots__ = ()
  820. def _literal_coercion(self, element, *, argname=None, **kw):
  821. if element is None:
  822. return elements.Null()
  823. elif element is False:
  824. return elements.False_()
  825. elif element is True:
  826. return elements.True_()
  827. else:
  828. self._raise_for_expected(element, argname)
  829. class TruncatedLabelImpl(_StringOnly, RoleImpl):
  830. __slots__ = ()
  831. def _implicit_coercions(
  832. self,
  833. element: Any,
  834. resolved: Any,
  835. argname: Optional[str] = None,
  836. **kw: Any,
  837. ) -> Any:
  838. if isinstance(element, str):
  839. return resolved
  840. else:
  841. self._raise_for_expected(element, argname, resolved)
  842. def _literal_coercion(self, element, **kw):
  843. """coerce the given value to :class:`._truncated_label`.
  844. Existing :class:`._truncated_label` and
  845. :class:`._anonymous_label` objects are passed
  846. unchanged.
  847. """
  848. if isinstance(element, elements._truncated_label):
  849. return element
  850. else:
  851. return elements._truncated_label(element)
  852. class DDLExpressionImpl(_Deannotate, _CoerceLiterals, RoleImpl):
  853. __slots__ = ()
  854. _coerce_consts = True
  855. def _text_coercion(self, element, argname=None):
  856. # see #5754 for why we can't easily deprecate this coercion.
  857. # essentially expressions like postgresql_where would have to be
  858. # text() as they come back from reflection and we don't want to
  859. # have text() elements wired into the inspection dictionaries.
  860. return elements.TextClause(element)
  861. class DDLConstraintColumnImpl(_Deannotate, _ReturnsStringKey, RoleImpl):
  862. __slots__ = ()
  863. class DDLReferredColumnImpl(DDLConstraintColumnImpl):
  864. __slots__ = ()
  865. class LimitOffsetImpl(RoleImpl):
  866. __slots__ = ()
  867. def _implicit_coercions(
  868. self,
  869. element: Any,
  870. resolved: Any,
  871. argname: Optional[str] = None,
  872. **kw: Any,
  873. ) -> Any:
  874. if resolved is None:
  875. return None
  876. else:
  877. self._raise_for_expected(element, argname, resolved)
  878. def _literal_coercion( # type: ignore[override]
  879. self, element, *, name, type_, **kw
  880. ):
  881. if element is None:
  882. return None
  883. else:
  884. value = util.asint(element)
  885. return selectable._OffsetLimitParam(
  886. name, value, type_=type_, unique=True
  887. )
  888. class LabeledColumnExprImpl(ExpressionElementImpl):
  889. __slots__ = ()
  890. def _implicit_coercions(
  891. self,
  892. element: Any,
  893. resolved: Any,
  894. argname: Optional[str] = None,
  895. **kw: Any,
  896. ) -> Any:
  897. if isinstance(resolved, roles.ExpressionElementRole):
  898. return resolved.label(None)
  899. else:
  900. new = super()._implicit_coercions(
  901. element, resolved, argname=argname, **kw
  902. )
  903. if isinstance(new, roles.ExpressionElementRole):
  904. return new.label(None)
  905. else:
  906. self._raise_for_expected(element, argname, resolved)
  907. class ColumnsClauseImpl(_SelectIsNotFrom, _CoerceLiterals, RoleImpl):
  908. __slots__ = ()
  909. _coerce_consts = True
  910. _coerce_numerics = True
  911. _coerce_star = True
  912. _guess_straight_column = re.compile(r"^\w\S*$", re.I)
  913. def _raise_for_expected(
  914. self, element, argname=None, resolved=None, *, advice=None, **kw
  915. ):
  916. if not advice and isinstance(element, list):
  917. advice = (
  918. f"Did you mean to say select("
  919. f"{', '.join(repr(e) for e in element)})?"
  920. )
  921. return super()._raise_for_expected(
  922. element, argname=argname, resolved=resolved, advice=advice, **kw
  923. )
  924. def _text_coercion(self, element, argname=None):
  925. element = str(element)
  926. guess_is_literal = not self._guess_straight_column.match(element)
  927. raise exc.ArgumentError(
  928. "Textual column expression %(column)r %(argname)sshould be "
  929. "explicitly declared with text(%(column)r), "
  930. "or use %(literal_column)s(%(column)r) "
  931. "for more specificity"
  932. % {
  933. "column": util.ellipses_string(element),
  934. "argname": "for argument %s" % (argname,) if argname else "",
  935. "literal_column": (
  936. "literal_column" if guess_is_literal else "column"
  937. ),
  938. }
  939. )
  940. class ReturnsRowsImpl(RoleImpl):
  941. __slots__ = ()
  942. class StatementImpl(_CoerceLiterals, RoleImpl):
  943. __slots__ = ()
  944. def _post_coercion(
  945. self, resolved, *, original_element, argname=None, **kw
  946. ):
  947. if resolved is not original_element and not isinstance(
  948. original_element, str
  949. ):
  950. # use same method as Connection uses; this will later raise
  951. # ObjectNotExecutableError
  952. try:
  953. original_element._execute_on_connection
  954. except AttributeError:
  955. util.warn_deprecated(
  956. "Object %r should not be used directly in a SQL statement "
  957. "context, such as passing to methods such as "
  958. "session.execute(). This usage will be disallowed in a "
  959. "future release. "
  960. "Please use Core select() / update() / delete() etc. "
  961. "with Session.execute() and other statement execution "
  962. "methods." % original_element,
  963. "1.4",
  964. )
  965. return resolved
  966. def _implicit_coercions(
  967. self,
  968. element: Any,
  969. resolved: Any,
  970. argname: Optional[str] = None,
  971. **kw: Any,
  972. ) -> Any:
  973. if resolved._is_lambda_element:
  974. return resolved
  975. else:
  976. return super()._implicit_coercions(
  977. element, resolved, argname=argname, **kw
  978. )
  979. class SelectStatementImpl(_NoTextCoercion, RoleImpl):
  980. __slots__ = ()
  981. def _implicit_coercions(
  982. self,
  983. element: Any,
  984. resolved: Any,
  985. argname: Optional[str] = None,
  986. **kw: Any,
  987. ) -> Any:
  988. if resolved._is_text_clause:
  989. return resolved.columns()
  990. else:
  991. self._raise_for_expected(element, argname, resolved)
  992. class HasCTEImpl(ReturnsRowsImpl):
  993. __slots__ = ()
  994. class IsCTEImpl(RoleImpl):
  995. __slots__ = ()
  996. class JoinTargetImpl(RoleImpl):
  997. __slots__ = ()
  998. _skip_clauseelement_for_target_match = True
  999. def _literal_coercion(self, element, *, argname=None, **kw):
  1000. self._raise_for_expected(element, argname)
  1001. def _implicit_coercions(
  1002. self,
  1003. element: Any,
  1004. resolved: Any,
  1005. argname: Optional[str] = None,
  1006. *,
  1007. legacy: bool = False,
  1008. **kw: Any,
  1009. ) -> Any:
  1010. if isinstance(element, roles.JoinTargetRole):
  1011. # note that this codepath no longer occurs as of
  1012. # #6550, unless JoinTargetImpl._skip_clauseelement_for_target_match
  1013. # were set to False.
  1014. return element
  1015. elif legacy and resolved._is_select_base:
  1016. util.warn_deprecated(
  1017. "Implicit coercion of SELECT and textual SELECT "
  1018. "constructs into FROM clauses is deprecated; please call "
  1019. ".subquery() on any Core select or ORM Query object in "
  1020. "order to produce a subquery object.",
  1021. version="1.4",
  1022. )
  1023. # TODO: doing _implicit_subquery here causes tests to fail,
  1024. # how was this working before? probably that ORM
  1025. # join logic treated it as a select and subquery would happen
  1026. # in _ORMJoin->Join
  1027. return resolved
  1028. else:
  1029. self._raise_for_expected(element, argname, resolved)
  1030. class FromClauseImpl(_SelectIsNotFrom, _NoTextCoercion, RoleImpl):
  1031. __slots__ = ()
  1032. def _implicit_coercions(
  1033. self,
  1034. element: Any,
  1035. resolved: Any,
  1036. argname: Optional[str] = None,
  1037. *,
  1038. explicit_subquery: bool = False,
  1039. allow_select: bool = True,
  1040. **kw: Any,
  1041. ) -> Any:
  1042. if resolved._is_select_base:
  1043. if explicit_subquery:
  1044. return resolved.subquery()
  1045. elif allow_select:
  1046. util.warn_deprecated(
  1047. "Implicit coercion of SELECT and textual SELECT "
  1048. "constructs into FROM clauses is deprecated; please call "
  1049. ".subquery() on any Core select or ORM Query object in "
  1050. "order to produce a subquery object.",
  1051. version="1.4",
  1052. )
  1053. return resolved._implicit_subquery
  1054. elif resolved._is_text_clause:
  1055. return resolved
  1056. else:
  1057. self._raise_for_expected(element, argname, resolved)
  1058. def _post_coercion(self, element, *, deannotate=False, **kw):
  1059. if deannotate:
  1060. return element._deannotate()
  1061. else:
  1062. return element
  1063. class StrictFromClauseImpl(FromClauseImpl):
  1064. __slots__ = ()
  1065. def _implicit_coercions(
  1066. self,
  1067. element: Any,
  1068. resolved: Any,
  1069. argname: Optional[str] = None,
  1070. *,
  1071. allow_select: bool = False,
  1072. **kw: Any,
  1073. ) -> Any:
  1074. if resolved._is_select_base and allow_select:
  1075. util.warn_deprecated(
  1076. "Implicit coercion of SELECT and textual SELECT constructs "
  1077. "into FROM clauses is deprecated; please call .subquery() "
  1078. "on any Core select or ORM Query object in order to produce a "
  1079. "subquery object.",
  1080. version="1.4",
  1081. )
  1082. return resolved._implicit_subquery
  1083. else:
  1084. self._raise_for_expected(element, argname, resolved)
  1085. class AnonymizedFromClauseImpl(StrictFromClauseImpl):
  1086. __slots__ = ()
  1087. def _post_coercion(self, element, *, flat=False, name=None, **kw):
  1088. assert name is None
  1089. return element._anonymous_fromclause(flat=flat)
  1090. class DMLTableImpl(_SelectIsNotFrom, _NoTextCoercion, RoleImpl):
  1091. __slots__ = ()
  1092. def _post_coercion(self, element, **kw):
  1093. if "dml_table" in element._annotations:
  1094. return element._annotations["dml_table"]
  1095. else:
  1096. return element
  1097. class DMLSelectImpl(_NoTextCoercion, RoleImpl):
  1098. __slots__ = ()
  1099. def _implicit_coercions(
  1100. self,
  1101. element: Any,
  1102. resolved: Any,
  1103. argname: Optional[str] = None,
  1104. **kw: Any,
  1105. ) -> Any:
  1106. if resolved._is_from_clause:
  1107. if (
  1108. isinstance(resolved, selectable.Alias)
  1109. and resolved.element._is_select_base
  1110. ):
  1111. return resolved.element
  1112. else:
  1113. return resolved.select()
  1114. else:
  1115. self._raise_for_expected(element, argname, resolved)
  1116. class CompoundElementImpl(_NoTextCoercion, RoleImpl):
  1117. __slots__ = ()
  1118. def _raise_for_expected(self, element, argname=None, resolved=None, **kw):
  1119. if isinstance(element, roles.FromClauseRole):
  1120. if element._is_subquery:
  1121. advice = (
  1122. "Use the plain select() object without "
  1123. "calling .subquery() or .alias()."
  1124. )
  1125. else:
  1126. advice = (
  1127. "To SELECT from any FROM clause, use the .select() method."
  1128. )
  1129. else:
  1130. advice = None
  1131. return super()._raise_for_expected(
  1132. element, argname=argname, resolved=resolved, advice=advice, **kw
  1133. )
  1134. _impl_lookup = {}
  1135. for name in dir(roles):
  1136. cls = getattr(roles, name)
  1137. if name.endswith("Role"):
  1138. name = name.replace("Role", "Impl")
  1139. if name in globals():
  1140. impl = globals()[name](cls)
  1141. _impl_lookup[cls] = impl
  1142. if not TYPE_CHECKING:
  1143. ee_impl = _impl_lookup[roles.ExpressionElementRole]
  1144. for py_type in (int, bool, str, float):
  1145. _impl_lookup[roles.ExpressionElementRole[py_type]] = ee_impl