def _apply_type_to_mapped_statement(
api: SemanticAnalyzerPluginInterface,
stmt: AssignmentStmt,
lvalue: NameExpr,
left_hand_explicit_type: Optional[Union[Instance, UnionType]],
python_type_for_type: Union[Instance, UnionType],
) -> None:
"""Apply the Mapped[<type>] annotation and right hand object to a
declarative assignment statement.
This converts a Python declarative class statement such as::
class User(Base):
# ...
attrname = Column(Integer)
To one that describes the final Python behavior to Mypy::
class User(Base):
# ...
attrname : Mapped[Optional[int]] = <meaningless temp node>
"""
descriptor = api.modules["sqlalchemy.orm.attributes"].names["Mapped"]
left_node = lvalue.node
inst = Instance(descriptor.node, [python_type_for_type])
if left_hand_explicit_type is not None:
left_node.type = Instance(descriptor.node, [left_hand_explicit_type])
else:
lvalue.is_inferred_def = False
left_node.type = inst
# so to have it skip the right side totally, we can do this:
# stmt.rvalue = TempNode(AnyType(TypeOfAny.special_form))
# however, if we instead manufacture a new node that uses the old
# one, then we can still get type checking for the call itself,
# e.g. the Column, relationship() call, etc.
# rewrite the node as:
# <attr> : Mapped[<typ>] =
# _sa_Mapped._empty_constructor(<original CallExpr from rvalue>)
# the original right-hand side is maintained so it gets type checked
# internally
api.add_symbol_table_node("_sa_Mapped", descriptor)
column_descriptor = nodes.NameExpr("_sa_Mapped")
column_descriptor.fullname = "sqlalchemy.orm.Mapped"
mm = nodes.MemberExpr(column_descriptor, "_empty_constructor")
orig_call_expr = stmt.rvalue
stmt.rvalue = CallExpr(
mm,
[orig_call_expr],
[nodes.ARG_POS],
["arg1"],
)
def _field_from_field_def(
self,
stmt: nodes.AssignmentStmt,
name: nodes.NameExpr,
sym: nodes.SymbolTableNode,
):
field = super()._field_from_field_def(stmt, name, sym)
if field is None:
return None
else:
assert isinstance(sym.node, nodes.Var)
sym.node.is_initialized_in_class = False
name.is_inferred_def = False
rhs = stmt.rvalue
if not isinstance(rhs, nodes.CastExpr):
stmt.rvalue = nodes.CastExpr(
typ=field.type,
expr=rhs,
)
stmt.rvalue.line = rhs.line
stmt.rvalue.column = rhs.column
return field
def apply_type_to_mapped_statement(
api: SemanticAnalyzerPluginInterface,
stmt: AssignmentStmt,
lvalue: NameExpr,
left_hand_explicit_type: Optional[ProperType],
python_type_for_type: Optional[ProperType],
) -> None:
"""Apply the Mapped[<type>] annotation and right hand object to a
declarative assignment statement.
This converts a Python declarative class statement such as::
class User(Base):
# ...
attrname = Column(Integer)
To one that describes the final Python behavior to Mypy::
class User(Base):
# ...
attrname : Mapped[Optional[int]] = <meaningless temp node>
"""
left_node = lvalue.node
assert isinstance(left_node, Var)
if left_hand_explicit_type is not None:
left_node.type = api.named_type(
"__sa_Mapped", [left_hand_explicit_type]
)
else:
lvalue.is_inferred_def = False
left_node.type = api.named_type(
"__sa_Mapped",
[] if python_type_for_type is None else [python_type_for_type],
)
# so to have it skip the right side totally, we can do this:
# stmt.rvalue = TempNode(AnyType(TypeOfAny.special_form))
# however, if we instead manufacture a new node that uses the old
# one, then we can still get type checking for the call itself,
# e.g. the Column, relationship() call, etc.
# rewrite the node as:
# <attr> : Mapped[<typ>] =
# _sa_Mapped._empty_constructor(<original CallExpr from rvalue>)
# the original right-hand side is maintained so it gets type checked
# internally
stmt.rvalue = util.expr_to_mapped_constructor(stmt.rvalue)
def visit_assignment_stmt(self, s: AssignmentStmt) -> None:
super().visit_assignment_stmt(s)
if isinstance(s.lvalues[0], IndexExpr):
index = cast(IndexExpr, s.lvalues[0])
method_type = index.method_type
if self.dynamic_funcs[-1] or isinstance(method_type, AnyType):
lvalue_type = AnyType() # type: Type
else:
method_callable = cast(Callable, method_type)
# TODO arg_types[1] may not be reliable
lvalue_type = method_callable.arg_types[1]
else:
lvalue_type = self.get_type(s.lvalues[0])
s.rvalue = self.coerce2(s.rvalue, lvalue_type, self.get_type(s.rvalue), self.type_context())
def visit_assignment_stmt(self, s: AssignmentStmt) -> None:
super().visit_assignment_stmt(s)
if isinstance(s.lvalues[0], IndexExpr):
index = cast(IndexExpr, s.lvalues[0])
method_type = index.method_type
if self.dynamic_funcs[-1] or isinstance(method_type, AnyType):
lvalue_type = AnyType() # type: Type
else:
method_callable = cast(Callable, method_type)
# TODO arg_types[1] may not be reliable
lvalue_type = method_callable.arg_types[1]
else:
lvalue_type = self.get_type(s.lvalues[0])
s.rvalue = self.coerce2(s.rvalue, lvalue_type, self.get_type(s.rvalue),
self.type_context())