diff options
Diffstat (limited to 'lib/sqlalchemy/sql/schema.py')
| -rw-r--r-- | lib/sqlalchemy/sql/schema.py | 95 |
1 files changed, 62 insertions, 33 deletions
diff --git a/lib/sqlalchemy/sql/schema.py b/lib/sqlalchemy/sql/schema.py index 7206cfdba..0e3e24a14 100644 --- a/lib/sqlalchemy/sql/schema.py +++ b/lib/sqlalchemy/sql/schema.py @@ -37,6 +37,7 @@ import typing from typing import Any from typing import Callable from typing import Dict +from typing import Iterator from typing import List from typing import MutableMapping from typing import Optional @@ -54,7 +55,6 @@ from . import ddl from . import roles from . import type_api from . import visitors -from .base import ColumnCollection from .base import DedupeColumnCollection from .base import DialectKWArgs from .base import Executable @@ -78,6 +78,7 @@ from ..util.typing import Protocol from ..util.typing import TypeGuard if typing.TYPE_CHECKING: + from .base import ReadOnlyColumnCollection from .type_api import TypeEngine from ..engine import Connection from ..engine import Engine @@ -273,6 +274,16 @@ class Table(DialectKWArgs, HasSchemaAttr, TableClause): __visit_name__ = "table" + if TYPE_CHECKING: + + @util.ro_non_memoized_property + def primary_key(self) -> PrimaryKeyConstraint: + ... + + @util.ro_non_memoized_property + def foreign_keys(self) -> Set[ForeignKey]: + ... + constraints: Set[Constraint] """A collection of all :class:`_schema.Constraint` objects associated with this :class:`_schema.Table`. @@ -316,12 +327,18 @@ class Table(DialectKWArgs, HasSchemaAttr, TableClause): ] if TYPE_CHECKING: - - @util.non_memoized_property - def columns(self) -> ColumnCollection[Column[Any]]: + # we are upgrading .c and .columns to return Column, not + # ColumnClause. mypy typically sees this as incompatible because + # the contract of TableClause is that we can put a ColumnClause + # into this collection. does not recognize its immutability + # for the moment. + @util.ro_non_memoized_property + def columns(self) -> ReadOnlyColumnCollection[str, Column[Any]]: # type: ignore # noqa: E501 ... - c: ColumnCollection[Column[Any]] + @util.ro_non_memoized_property + def c(self) -> ReadOnlyColumnCollection[str, Column[Any]]: # type: ignore # noqa: E501 + ... def _gen_cache_key(self, anon_map, bindparams): if self._annotations: @@ -737,7 +754,7 @@ class Table(DialectKWArgs, HasSchemaAttr, TableClause): PrimaryKeyConstraint( _implicit_generated=True )._set_parent_with_dispatch(self) - self.foreign_keys = set() + self.foreign_keys = set() # type: ignore self._extra_dependencies = set() if self.schema is not None: self.fullname = "%s.%s" % (self.schema, self.name) @@ -3537,7 +3554,7 @@ class ColumnCollectionMixin: """ - columns: ColumnCollection[Column[Any]] + _columns: DedupeColumnCollection[Column[Any]] _allow_multiple_tables = False @@ -3551,7 +3568,7 @@ class ColumnCollectionMixin: def __init__(self, *columns, **kw): _autoattach = kw.pop("_autoattach", True) self._column_flag = kw.pop("_column_flag", False) - self.columns = DedupeColumnCollection() + self._columns = DedupeColumnCollection() processed_expressions = kw.pop("_gather_expressions", None) if processed_expressions is not None: @@ -3624,6 +3641,14 @@ class ColumnCollectionMixin: ) ) + @util.ro_memoized_property + def columns(self) -> ReadOnlyColumnCollection[str, Column[Any]]: + return self._columns.as_readonly() + + @util.ro_memoized_property + def c(self) -> ReadOnlyColumnCollection[str, Column[Any]]: + return self._columns.as_readonly() + def _col_expressions(self, table: Table) -> List[Column[Any]]: return [ table.c[col] if isinstance(col, str) else col @@ -3635,7 +3660,7 @@ class ColumnCollectionMixin: assert isinstance(parent, Table) for col in self._col_expressions(parent): if col is not None: - self.columns.add(col) + self._columns.add(col) class ColumnCollectionConstraint(ColumnCollectionMixin, Constraint): @@ -3668,7 +3693,7 @@ class ColumnCollectionConstraint(ColumnCollectionMixin, Constraint): self, *columns, _autoattach=_autoattach, _column_flag=_column_flag ) - columns: DedupeColumnCollection[Column[Any]] + columns: ReadOnlyColumnCollection[str, Column[Any]] """A :class:`_expression.ColumnCollection` representing the set of columns for this constraint. @@ -3679,7 +3704,7 @@ class ColumnCollectionConstraint(ColumnCollectionMixin, Constraint): ColumnCollectionMixin._set_parent(self, table) def __contains__(self, x): - return x in self.columns + return x in self._columns @util.deprecated( "1.4", @@ -3708,7 +3733,7 @@ class ColumnCollectionConstraint(ColumnCollectionMixin, Constraint): initially=self.initially, *[ _copy_expression(expr, self.parent, target_table) - for expr in self.columns + for expr in self._columns ], **constraint_kwargs, ) @@ -3723,13 +3748,13 @@ class ColumnCollectionConstraint(ColumnCollectionMixin, Constraint): """ - return self.columns.contains_column(col) + return self._columns.contains_column(col) - def __iter__(self): - return iter(self.columns) + def __iter__(self) -> Iterator[Column[Any]]: + return iter(self._columns) - def __len__(self): - return len(self.columns) + def __len__(self) -> int: + return len(self._columns) class CheckConstraint(ColumnCollectionConstraint): @@ -4002,10 +4027,10 @@ class ForeignKeyConstraint(ColumnCollectionConstraint): self._set_parent_with_dispatch(table) def _append_element(self, column: Column[Any], fk: ForeignKey) -> None: - self.columns.add(column) + self._columns.add(column) self.elements.append(fk) - columns: DedupeColumnCollection[Column[Any]] + columns: ReadOnlyColumnCollection[str, Column[Any]] """A :class:`_expression.ColumnCollection` representing the set of columns for this constraint. @@ -4072,7 +4097,7 @@ class ForeignKeyConstraint(ColumnCollectionConstraint): """ if hasattr(self, "parent"): - return self.columns.keys() + return self._columns.keys() else: return [ col.key if isinstance(col, ColumnElement) else str(col) @@ -4095,7 +4120,7 @@ class ForeignKeyConstraint(ColumnCollectionConstraint): "named '%s' is present." % (table.description, ke.args[0]) ) from ke - for col, fk in zip(self.columns, self.elements): + for col, fk in zip(self._columns, self.elements): if not hasattr(fk, "parent") or fk.parent is not col: fk._set_parent_with_dispatch(col) @@ -4226,7 +4251,11 @@ class PrimaryKeyConstraint(ColumnCollectionConstraint): table.constraints.add(self) table_pks = [c for c in table.c if c.primary_key] - if self.columns and table_pks and set(table_pks) != set(self.columns): + if ( + self._columns + and table_pks + and set(table_pks) != set(self._columns) + ): util.warn( "Table '%s' specifies columns %s as primary_key=True, " "not matching locally specified columns %s; setting the " @@ -4235,18 +4264,18 @@ class PrimaryKeyConstraint(ColumnCollectionConstraint): % ( table.name, ", ".join("'%s'" % c.name for c in table_pks), - ", ".join("'%s'" % c.name for c in self.columns), - ", ".join("'%s'" % c.name for c in self.columns), + ", ".join("'%s'" % c.name for c in self._columns), + ", ".join("'%s'" % c.name for c in self._columns), ) ) table_pks[:] = [] - for c in self.columns: + for c in self._columns: c.primary_key = True if c._user_defined_nullable is NULL_UNSPECIFIED: c.nullable = False if table_pks: - self.columns.extend(table_pks) + self._columns.extend(table_pks) def _reload(self, columns): """repopulate this :class:`.PrimaryKeyConstraint` given @@ -4272,14 +4301,14 @@ class PrimaryKeyConstraint(ColumnCollectionConstraint): for col in columns: col.primary_key = True - self.columns.extend(columns) + self._columns.extend(columns) PrimaryKeyConstraint._autoincrement_column._reset(self) self._set_parent_with_dispatch(self.table) def _replace(self, col): PrimaryKeyConstraint._autoincrement_column._reset(self) - self.columns.replace(col) + self._columns.replace(col) self.dispatch._sa_event_column_added_to_pk_constraint(self, col) @@ -4288,9 +4317,9 @@ class PrimaryKeyConstraint(ColumnCollectionConstraint): autoinc = self._autoincrement_column if autoinc is not None: - return [autoinc] + [c for c in self.columns if c is not autoinc] + return [autoinc] + [c for c in self._columns if c is not autoinc] else: - return list(self.columns) + return list(self._columns) @util.memoized_property def _autoincrement_column(self): @@ -4323,8 +4352,8 @@ class PrimaryKeyConstraint(ColumnCollectionConstraint): return False return True - if len(self.columns) == 1: - col = list(self.columns)[0] + if len(self._columns) == 1: + col = list(self._columns)[0] if col.autoincrement is True: _validate_autoinc(col, True) @@ -4337,7 +4366,7 @@ class PrimaryKeyConstraint(ColumnCollectionConstraint): else: autoinc = None - for col in self.columns: + for col in self._columns: if col.autoincrement is True: _validate_autoinc(col, True) if autoinc is not None: |