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Diffstat (limited to 'lib/sqlalchemy/sql/coercions.py')
| -rw-r--r-- | lib/sqlalchemy/sql/coercions.py | 1096 |
1 files changed, 1096 insertions, 0 deletions
diff --git a/lib/sqlalchemy/sql/coercions.py b/lib/sqlalchemy/sql/coercions.py new file mode 100644 index 0000000..8cc73cb --- /dev/null +++ b/lib/sqlalchemy/sql/coercions.py @@ -0,0 +1,1096 @@ +# sql/coercions.py +# Copyright (C) 2005-2022 the SQLAlchemy authors and contributors +# <see AUTHORS file> +# +# This module is part of SQLAlchemy and is released under +# the MIT License: https://www.opensource.org/licenses/mit-license.php + +import numbers +import re + +from . import operators +from . import roles +from . import visitors +from .base import ExecutableOption +from .base import Options +from .traversals import HasCacheKey +from .visitors import Visitable +from .. import exc +from .. import inspection +from .. import util +from ..util import collections_abc + + +elements = None +lambdas = None +schema = None +selectable = None +sqltypes = None +traversals = None + + +def _is_literal(element): + """Return whether or not the element is a "literal" in the context + of a SQL expression construct. + + """ + + return ( + not isinstance( + element, + (Visitable, schema.SchemaEventTarget), + ) + and not hasattr(element, "__clause_element__") + ) + + +def _deep_is_literal(element): + """Return whether or not the element is a "literal" in the context + of a SQL expression construct. + + does a deeper more esoteric check than _is_literal. is used + for lambda elements that have to distinguish values that would + be bound vs. not without any context. + + """ + + if isinstance(element, collections_abc.Sequence) and not isinstance( + element, str + ): + for elem in element: + if not _deep_is_literal(elem): + return False + else: + return True + + return ( + not isinstance( + element, + ( + Visitable, + schema.SchemaEventTarget, + HasCacheKey, + Options, + util.langhelpers._symbol, + ), + ) + and not hasattr(element, "__clause_element__") + and ( + not isinstance(element, type) + or not issubclass(element, HasCacheKey) + ) + ) + + +def _document_text_coercion(paramname, meth_rst, param_rst): + return util.add_parameter_text( + paramname, + ( + ".. warning:: " + "The %s argument to %s can be passed as a Python string argument, " + "which will be treated " + "as **trusted SQL text** and rendered as given. **DO NOT PASS " + "UNTRUSTED INPUT TO THIS PARAMETER**." + ) + % (param_rst, meth_rst), + ) + + +def _expression_collection_was_a_list(attrname, fnname, args): + if args and isinstance(args[0], (list, set, dict)) and len(args) == 1: + if isinstance(args[0], list): + util.warn_deprecated_20( + 'The "%s" argument to %s(), when referring to a sequence ' + "of items, is now passed as a series of positional " + "elements, rather than as a list. " % (attrname, fnname) + ) + return args[0] + else: + return args + + +def expect( + role, + element, + apply_propagate_attrs=None, + argname=None, + post_inspect=False, + **kw +): + if ( + role.allows_lambda + # note callable() will not invoke a __getattr__() method, whereas + # hasattr(obj, "__call__") will. by keeping the callable() check here + # we prevent most needless calls to hasattr() and therefore + # __getattr__(), which is present on ColumnElement. + and callable(element) + and hasattr(element, "__code__") + ): + return lambdas.LambdaElement( + element, + role, + lambdas.LambdaOptions(**kw), + apply_propagate_attrs=apply_propagate_attrs, + ) + + # major case is that we are given a ClauseElement already, skip more + # elaborate logic up front if possible + impl = _impl_lookup[role] + + original_element = element + + if not isinstance( + element, + (elements.ClauseElement, schema.SchemaItem, schema.FetchedValue), + ): + resolved = None + + if impl._resolve_literal_only: + resolved = impl._literal_coercion(element, **kw) + else: + + original_element = element + + is_clause_element = False + + # this is a special performance optimization for ORM + # joins used by JoinTargetImpl that we don't go through the + # work of creating __clause_element__() when we only need the + # original QueryableAttribute, as the former will do clause + # adaption and all that which is just thrown away here. + if ( + impl._skip_clauseelement_for_target_match + and isinstance(element, role) + and hasattr(element, "__clause_element__") + ): + is_clause_element = True + else: + while hasattr(element, "__clause_element__"): + is_clause_element = True + + if not getattr(element, "is_clause_element", False): + element = element.__clause_element__() + else: + break + + if not is_clause_element: + if impl._use_inspection: + insp = inspection.inspect(element, raiseerr=False) + if insp is not None: + if post_inspect: + insp._post_inspect + try: + resolved = insp.__clause_element__() + except AttributeError: + impl._raise_for_expected(original_element, argname) + + if resolved is None: + resolved = impl._literal_coercion( + element, argname=argname, **kw + ) + else: + resolved = element + else: + resolved = element + if ( + apply_propagate_attrs is not None + and not apply_propagate_attrs._propagate_attrs + and resolved._propagate_attrs + ): + apply_propagate_attrs._propagate_attrs = resolved._propagate_attrs + + if impl._role_class in resolved.__class__.__mro__: + if impl._post_coercion: + resolved = impl._post_coercion( + resolved, + argname=argname, + original_element=original_element, + **kw + ) + return resolved + else: + return impl._implicit_coercions( + original_element, resolved, argname=argname, **kw + ) + + +def expect_as_key(role, element, **kw): + kw["as_key"] = True + return expect(role, element, **kw) + + +def expect_col_expression_collection(role, expressions): + for expr in expressions: + strname = None + column = None + + resolved = expect(role, expr) + if isinstance(resolved, util.string_types): + strname = resolved = expr + else: + cols = [] + visitors.traverse(resolved, {}, {"column": cols.append}) + if cols: + column = cols[0] + add_element = column if column is not None else strname + yield resolved, column, strname, add_element + + +class RoleImpl(object): + __slots__ = ("_role_class", "name", "_use_inspection") + + def _literal_coercion(self, element, **kw): + raise NotImplementedError() + + _post_coercion = None + _resolve_literal_only = False + _skip_clauseelement_for_target_match = False + + def __init__(self, role_class): + self._role_class = role_class + self.name = role_class._role_name + self._use_inspection = issubclass(role_class, roles.UsesInspection) + + def _implicit_coercions(self, element, resolved, argname=None, **kw): + self._raise_for_expected(element, argname, resolved) + + def _raise_for_expected( + self, + element, + argname=None, + resolved=None, + advice=None, + code=None, + err=None, + ): + if resolved is not None and resolved is not element: + got = "%r object resolved from %r object" % (resolved, element) + else: + got = repr(element) + + if argname: + msg = "%s expected for argument %r; got %s." % ( + self.name, + argname, + got, + ) + else: + msg = "%s expected, got %s." % (self.name, got) + + if advice: + msg += " " + advice + + util.raise_(exc.ArgumentError(msg, code=code), replace_context=err) + + +class _Deannotate(object): + __slots__ = () + + def _post_coercion(self, resolved, **kw): + from .util import _deep_deannotate + + return _deep_deannotate(resolved) + + +class _StringOnly(object): + __slots__ = () + + _resolve_literal_only = True + + +class _ReturnsStringKey(object): + __slots__ = () + + def _implicit_coercions( + self, original_element, resolved, argname=None, **kw + ): + if isinstance(original_element, util.string_types): + return original_element + else: + self._raise_for_expected(original_element, argname, resolved) + + def _literal_coercion(self, element, **kw): + return element + + +class _ColumnCoercions(object): + __slots__ = () + + def _warn_for_scalar_subquery_coercion(self): + util.warn( + "implicitly coercing SELECT object to scalar subquery; " + "please use the .scalar_subquery() method to produce a scalar " + "subquery.", + ) + + def _implicit_coercions( + self, original_element, resolved, argname=None, **kw + ): + if not getattr(resolved, "is_clause_element", False): + self._raise_for_expected(original_element, argname, resolved) + elif resolved._is_select_statement: + self._warn_for_scalar_subquery_coercion() + return resolved.scalar_subquery() + elif resolved._is_from_clause and isinstance( + resolved, selectable.Subquery + ): + self._warn_for_scalar_subquery_coercion() + return resolved.element.scalar_subquery() + elif self._role_class.allows_lambda and resolved._is_lambda_element: + return resolved + else: + self._raise_for_expected(original_element, argname, resolved) + + +def _no_text_coercion( + element, argname=None, exc_cls=exc.ArgumentError, extra=None, err=None +): + util.raise_( + exc_cls( + "%(extra)sTextual SQL expression %(expr)r %(argname)sshould be " + "explicitly declared as text(%(expr)r)" + % { + "expr": util.ellipses_string(element), + "argname": "for argument %s" % (argname,) if argname else "", + "extra": "%s " % extra if extra else "", + } + ), + replace_context=err, + ) + + +class _NoTextCoercion(object): + __slots__ = () + + def _literal_coercion(self, element, argname=None, **kw): + if isinstance(element, util.string_types) and issubclass( + elements.TextClause, self._role_class + ): + _no_text_coercion(element, argname) + else: + self._raise_for_expected(element, argname) + + +class _CoerceLiterals(object): + __slots__ = () + _coerce_consts = False + _coerce_star = False + _coerce_numerics = False + + def _text_coercion(self, element, argname=None): + return _no_text_coercion(element, argname) + + def _literal_coercion(self, element, argname=None, **kw): + if isinstance(element, util.string_types): + if self._coerce_star and element == "*": + return elements.ColumnClause("*", is_literal=True) + else: + return self._text_coercion(element, argname, **kw) + + if self._coerce_consts: + if element is None: + return elements.Null() + elif element is False: + return elements.False_() + elif element is True: + return elements.True_() + + if self._coerce_numerics and isinstance(element, (numbers.Number)): + return elements.ColumnClause(str(element), is_literal=True) + + self._raise_for_expected(element, argname) + + +class LiteralValueImpl(RoleImpl): + _resolve_literal_only = True + + def _implicit_coercions( + self, element, resolved, argname, type_=None, **kw + ): + if not _is_literal(resolved): + self._raise_for_expected( + element, resolved=resolved, argname=argname, **kw + ) + + return elements.BindParameter(None, element, type_=type_, unique=True) + + def _literal_coercion(self, element, argname=None, type_=None, **kw): + return element + + +class _SelectIsNotFrom(object): + __slots__ = () + + def _raise_for_expected(self, element, argname=None, resolved=None, **kw): + if isinstance(element, roles.SelectStatementRole) or isinstance( + resolved, roles.SelectStatementRole + ): + advice = ( + "To create a " + "FROM clause from a %s object, use the .subquery() method." + % (resolved.__class__ if resolved is not None else element,) + ) + code = "89ve" + else: + advice = code = None + + return super(_SelectIsNotFrom, self)._raise_for_expected( + element, + argname=argname, + resolved=resolved, + advice=advice, + code=code, + **kw + ) + + +class HasCacheKeyImpl(RoleImpl): + __slots__ = () + + def _implicit_coercions( + self, original_element, resolved, argname=None, **kw + ): + if isinstance(original_element, traversals.HasCacheKey): + return original_element + else: + self._raise_for_expected(original_element, argname, resolved) + + def _literal_coercion(self, element, **kw): + return element + + +class ExecutableOptionImpl(RoleImpl): + __slots__ = () + + def _implicit_coercions( + self, original_element, resolved, argname=None, **kw + ): + if isinstance(original_element, ExecutableOption): + return original_element + else: + self._raise_for_expected(original_element, argname, resolved) + + def _literal_coercion(self, element, **kw): + return element + + +class ExpressionElementImpl(_ColumnCoercions, RoleImpl): + __slots__ = () + + def _literal_coercion( + self, element, name=None, type_=None, argname=None, is_crud=False, **kw + ): + if ( + element is None + and not is_crud + and (type_ is None or not type_.should_evaluate_none) + ): + # TODO: there's no test coverage now for the + # "should_evaluate_none" part of this, as outside of "crud" this + # codepath is not normally used except in some special cases + return elements.Null() + else: + try: + return elements.BindParameter( + name, element, type_, unique=True, _is_crud=is_crud + ) + except exc.ArgumentError as err: + self._raise_for_expected(element, err=err) + + def _raise_for_expected(self, element, argname=None, resolved=None, **kw): + if isinstance(element, roles.AnonymizedFromClauseRole): + advice = ( + "To create a " + "column expression from a FROM clause row " + "as a whole, use the .table_valued() method." + ) + else: + advice = None + + return super(ExpressionElementImpl, self)._raise_for_expected( + element, argname=argname, resolved=resolved, advice=advice, **kw + ) + + +class BinaryElementImpl(ExpressionElementImpl, RoleImpl): + + __slots__ = () + + def _literal_coercion( + self, element, expr, operator, bindparam_type=None, argname=None, **kw + ): + try: + return expr._bind_param(operator, element, type_=bindparam_type) + except exc.ArgumentError as err: + self._raise_for_expected(element, err=err) + + def _post_coercion(self, resolved, expr, bindparam_type=None, **kw): + if resolved.type._isnull and not expr.type._isnull: + resolved = resolved._with_binary_element_type( + bindparam_type if bindparam_type is not None else expr.type + ) + return resolved + + +class InElementImpl(RoleImpl): + __slots__ = () + + def _implicit_coercions( + self, original_element, resolved, argname=None, **kw + ): + if resolved._is_from_clause: + if ( + isinstance(resolved, selectable.Alias) + and resolved.element._is_select_statement + ): + self._warn_for_implicit_coercion(resolved) + return self._post_coercion(resolved.element, **kw) + else: + self._warn_for_implicit_coercion(resolved) + return self._post_coercion(resolved.select(), **kw) + else: + self._raise_for_expected(original_element, argname, resolved) + + def _warn_for_implicit_coercion(self, elem): + util.warn( + "Coercing %s object into a select() for use in IN(); " + "please pass a select() construct explicitly" + % (elem.__class__.__name__) + ) + + def _literal_coercion(self, element, expr, operator, **kw): + if isinstance(element, collections_abc.Iterable) and not isinstance( + element, util.string_types + ): + non_literal_expressions = {} + element = list(element) + for o in element: + if not _is_literal(o): + if not isinstance(o, operators.ColumnOperators): + self._raise_for_expected(element, **kw) + else: + non_literal_expressions[o] = o + elif o is None: + non_literal_expressions[o] = elements.Null() + + if non_literal_expressions: + return elements.ClauseList( + *[ + non_literal_expressions[o] + if o in non_literal_expressions + else expr._bind_param(operator, o) + for o in element + ] + ) + else: + return expr._bind_param(operator, element, expanding=True) + + else: + self._raise_for_expected(element, **kw) + + def _post_coercion(self, element, expr, operator, **kw): + if element._is_select_statement: + # for IN, we are doing scalar_subquery() coercion without + # a warning + return element.scalar_subquery() + elif isinstance(element, elements.ClauseList): + assert not len(element.clauses) == 0 + return element.self_group(against=operator) + + elif isinstance(element, elements.BindParameter): + element = element._clone(maintain_key=True) + element.expanding = True + element.expand_op = operator + + return element + else: + return element + + +class OnClauseImpl(_CoerceLiterals, _ColumnCoercions, RoleImpl): + __slots__ = () + + _coerce_consts = True + + def _implicit_coercions( + self, original_element, resolved, argname=None, legacy=False, **kw + ): + if legacy and isinstance(resolved, str): + return resolved + else: + return super(OnClauseImpl, self)._implicit_coercions( + original_element, + resolved, + argname=argname, + legacy=legacy, + **kw + ) + + def _text_coercion(self, element, argname=None, legacy=False): + if legacy and isinstance(element, str): + util.warn_deprecated_20( + "Using strings to indicate relationship names in " + "Query.join() is deprecated and will be removed in " + "SQLAlchemy 2.0. Please use the class-bound attribute " + "directly." + ) + return element + + return super(OnClauseImpl, self)._text_coercion(element, argname) + + def _post_coercion(self, resolved, original_element=None, **kw): + # this is a hack right now as we want to use coercion on an + # ORM InstrumentedAttribute, but we want to return the object + # itself if it is one, not its clause element. + # ORM context _join and _legacy_join() would need to be improved + # to look for annotations in a clause element form. + if isinstance(original_element, roles.JoinTargetRole): + return original_element + return resolved + + +class WhereHavingImpl(_CoerceLiterals, _ColumnCoercions, RoleImpl): + __slots__ = () + + _coerce_consts = True + + def _text_coercion(self, element, argname=None): + return _no_text_coercion(element, argname) + + +class StatementOptionImpl(_CoerceLiterals, RoleImpl): + __slots__ = () + + _coerce_consts = True + + def _text_coercion(self, element, argname=None): + return elements.TextClause(element) + + +class ColumnArgumentImpl(_NoTextCoercion, RoleImpl): + __slots__ = () + + +class ColumnArgumentOrKeyImpl(_ReturnsStringKey, RoleImpl): + __slots__ = () + + +class StrAsPlainColumnImpl(_CoerceLiterals, RoleImpl): + __slots__ = () + + def _text_coercion(self, element, argname=None): + return elements.ColumnClause(element) + + +class ByOfImpl(_CoerceLiterals, _ColumnCoercions, RoleImpl, roles.ByOfRole): + + __slots__ = () + + _coerce_consts = True + + def _text_coercion(self, element, argname=None): + return elements._textual_label_reference(element) + + +class OrderByImpl(ByOfImpl, RoleImpl): + __slots__ = () + + def _post_coercion(self, resolved, **kw): + if ( + isinstance(resolved, self._role_class) + and resolved._order_by_label_element is not None + ): + return elements._label_reference(resolved) + else: + return resolved + + +class GroupByImpl(ByOfImpl, RoleImpl): + __slots__ = () + + def _implicit_coercions( + self, original_element, resolved, argname=None, **kw + ): + if isinstance(resolved, roles.StrictFromClauseRole): + return elements.ClauseList(*resolved.c) + else: + return resolved + + +class DMLColumnImpl(_ReturnsStringKey, RoleImpl): + __slots__ = () + + def _post_coercion(self, element, as_key=False, **kw): + if as_key: + return element.key + else: + return element + + +class ConstExprImpl(RoleImpl): + __slots__ = () + + def _literal_coercion(self, element, argname=None, **kw): + if element is None: + return elements.Null() + elif element is False: + return elements.False_() + elif element is True: + return elements.True_() + else: + self._raise_for_expected(element, argname) + + +class TruncatedLabelImpl(_StringOnly, RoleImpl): + __slots__ = () + + def _implicit_coercions( + self, original_element, resolved, argname=None, **kw + ): + if isinstance(original_element, util.string_types): + return resolved + else: + self._raise_for_expected(original_element, argname, resolved) + + def _literal_coercion(self, element, argname=None, **kw): + """coerce the given value to :class:`._truncated_label`. + + Existing :class:`._truncated_label` and + :class:`._anonymous_label` objects are passed + unchanged. + """ + + if isinstance(element, elements._truncated_label): + return element + else: + return elements._truncated_label(element) + + +class DDLExpressionImpl(_Deannotate, _CoerceLiterals, RoleImpl): + + __slots__ = () + + _coerce_consts = True + + def _text_coercion(self, element, argname=None): + # see #5754 for why we can't easily deprecate this coercion. + # essentially expressions like postgresql_where would have to be + # text() as they come back from reflection and we don't want to + # have text() elements wired into the inspection dictionaries. + return elements.TextClause(element) + + +class DDLConstraintColumnImpl(_Deannotate, _ReturnsStringKey, RoleImpl): + __slots__ = () + + +class DDLReferredColumnImpl(DDLConstraintColumnImpl): + __slots__ = () + + +class LimitOffsetImpl(RoleImpl): + __slots__ = () + + def _implicit_coercions(self, element, resolved, argname=None, **kw): + if resolved is None: + return None + else: + self._raise_for_expected(element, argname, resolved) + + def _literal_coercion(self, element, name, type_, **kw): + if element is None: + return None + else: + value = util.asint(element) + return selectable._OffsetLimitParam( + name, value, type_=type_, unique=True + ) + + +class LabeledColumnExprImpl(ExpressionElementImpl): + __slots__ = () + + def _implicit_coercions( + self, original_element, resolved, argname=None, **kw + ): + if isinstance(resolved, roles.ExpressionElementRole): + return resolved.label(None) + else: + new = super(LabeledColumnExprImpl, self)._implicit_coercions( + original_element, resolved, argname=argname, **kw + ) + if isinstance(new, roles.ExpressionElementRole): + return new.label(None) + else: + self._raise_for_expected(original_element, argname, resolved) + + +class ColumnsClauseImpl(_SelectIsNotFrom, _CoerceLiterals, RoleImpl): + __slots__ = () + + _coerce_consts = True + _coerce_numerics = True + _coerce_star = True + + _guess_straight_column = re.compile(r"^\w\S*$", re.I) + + def _text_coercion(self, element, argname=None): + element = str(element) + + guess_is_literal = not self._guess_straight_column.match(element) + raise exc.ArgumentError( + "Textual column expression %(column)r %(argname)sshould be " + "explicitly declared with text(%(column)r), " + "or use %(literal_column)s(%(column)r) " + "for more specificity" + % { + "column": util.ellipses_string(element), + "argname": "for argument %s" % (argname,) if argname else "", + "literal_column": "literal_column" + if guess_is_literal + else "column", + } + ) + + +class ReturnsRowsImpl(RoleImpl): + __slots__ = () + + +class StatementImpl(_CoerceLiterals, RoleImpl): + __slots__ = () + + def _post_coercion(self, resolved, original_element, argname=None, **kw): + if resolved is not original_element and not isinstance( + original_element, util.string_types + ): + # use same method as Connection uses; this will later raise + # ObjectNotExecutableError + try: + original_element._execute_on_connection + except AttributeError: + util.warn_deprecated( + "Object %r should not be used directly in a SQL statement " + "context, such as passing to methods such as " + "session.execute(). This usage will be disallowed in a " + "future release. " + "Please use Core select() / update() / delete() etc. " + "with Session.execute() and other statement execution " + "methods." % original_element, + "1.4", + ) + + return resolved + + def _implicit_coercions( + self, original_element, resolved, argname=None, **kw + ): + if resolved._is_lambda_element: + return resolved + else: + return super(StatementImpl, self)._implicit_coercions( + original_element, resolved, argname=argname, **kw + ) + + def _text_coercion(self, element, argname=None): + util.warn_deprecated_20( + "Using plain strings to indicate SQL statements without using " + "the text() construct is " + "deprecated and will be removed in version 2.0. Ensure plain " + "SQL statements are passed using the text() construct." + ) + return elements.TextClause(element) + + +class SelectStatementImpl(_NoTextCoercion, RoleImpl): + __slots__ = () + + def _implicit_coercions( + self, original_element, resolved, argname=None, **kw + ): + if resolved._is_text_clause: + return resolved.columns() + else: + self._raise_for_expected(original_element, argname, resolved) + + +class HasCTEImpl(ReturnsRowsImpl): + __slots__ = () + + +class IsCTEImpl(RoleImpl): + __slots__ = () + + +class JoinTargetImpl(RoleImpl): + __slots__ = () + + _skip_clauseelement_for_target_match = True + + def _literal_coercion(self, element, legacy=False, **kw): + if isinstance(element, str): + return element + + def _implicit_coercions( + self, original_element, resolved, argname=None, legacy=False, **kw + ): + if isinstance(original_element, roles.JoinTargetRole): + # note that this codepath no longer occurs as of + # #6550, unless JoinTargetImpl._skip_clauseelement_for_target_match + # were set to False. + return original_element + elif legacy and isinstance(resolved, str): + util.warn_deprecated_20( + "Using strings to indicate relationship names in " + "Query.join() is deprecated and will be removed in " + "SQLAlchemy 2.0. Please use the class-bound attribute " + "directly." + ) + return resolved + elif legacy and isinstance(resolved, roles.WhereHavingRole): + return resolved + elif legacy and resolved._is_select_statement: + util.warn_deprecated( + "Implicit coercion of SELECT and textual SELECT " + "constructs into FROM clauses is deprecated; please call " + ".subquery() on any Core select or ORM Query object in " + "order to produce a subquery object.", + version="1.4", + ) + # TODO: doing _implicit_subquery here causes tests to fail, + # how was this working before? probably that ORM + # join logic treated it as a select and subquery would happen + # in _ORMJoin->Join + return resolved + else: + self._raise_for_expected(original_element, argname, resolved) + + +class FromClauseImpl(_SelectIsNotFrom, _NoTextCoercion, RoleImpl): + __slots__ = () + + def _implicit_coercions( + self, + original_element, + resolved, + argname=None, + explicit_subquery=False, + allow_select=True, + **kw + ): + if resolved._is_select_statement: + if explicit_subquery: + return resolved.subquery() + elif allow_select: + util.warn_deprecated( + "Implicit coercion of SELECT and textual SELECT " + "constructs into FROM clauses is deprecated; please call " + ".subquery() on any Core select or ORM Query object in " + "order to produce a subquery object.", + version="1.4", + ) + return resolved._implicit_subquery + elif resolved._is_text_clause: + return resolved + else: + self._raise_for_expected(original_element, argname, resolved) + + def _post_coercion(self, element, deannotate=False, **kw): + if deannotate: + return element._deannotate() + else: + return element + + +class StrictFromClauseImpl(FromClauseImpl): + __slots__ = () + + def _implicit_coercions( + self, + original_element, + resolved, + argname=None, + allow_select=False, + **kw + ): + if resolved._is_select_statement and allow_select: + util.warn_deprecated( + "Implicit coercion of SELECT and textual SELECT constructs " + "into FROM clauses is deprecated; please call .subquery() " + "on any Core select or ORM Query object in order to produce a " + "subquery object.", + version="1.4", + ) + return resolved._implicit_subquery + else: + self._raise_for_expected(original_element, argname, resolved) + + +class AnonymizedFromClauseImpl(StrictFromClauseImpl): + __slots__ = () + + def _post_coercion(self, element, flat=False, name=None, **kw): + assert name is None + + return element._anonymous_fromclause(flat=flat) + + +class DMLTableImpl(_SelectIsNotFrom, _NoTextCoercion, RoleImpl): + __slots__ = () + + def _post_coercion(self, element, **kw): + if "dml_table" in element._annotations: + return element._annotations["dml_table"] + else: + return element + + +class DMLSelectImpl(_NoTextCoercion, RoleImpl): + __slots__ = () + + def _implicit_coercions( + self, original_element, resolved, argname=None, **kw + ): + if resolved._is_from_clause: + if ( + isinstance(resolved, selectable.Alias) + and resolved.element._is_select_statement + ): + return resolved.element + else: + return resolved.select() + else: + self._raise_for_expected(original_element, argname, resolved) + + +class CompoundElementImpl(_NoTextCoercion, RoleImpl): + __slots__ = () + + def _raise_for_expected(self, element, argname=None, resolved=None, **kw): + if isinstance(element, roles.FromClauseRole): + if element._is_subquery: + advice = ( + "Use the plain select() object without " + "calling .subquery() or .alias()." + ) + else: + advice = ( + "To SELECT from any FROM clause, use the .select() method." + ) + else: + advice = None + return super(CompoundElementImpl, self)._raise_for_expected( + element, argname=argname, resolved=resolved, advice=advice, **kw + ) + + +_impl_lookup = {} + + +for name in dir(roles): + cls = getattr(roles, name) + if name.endswith("Role"): + name = name.replace("Role", "Impl") + if name in globals(): + impl = globals()[name](cls) + _impl_lookup[cls] = impl |