def analyze_class_attribute_access(itype: Instance, name: str,
context: Context, is_lvalue: bool,
builtin_type: Callable[[str], Instance],
not_ready_callback: Callable[[str, Context],
None],
msg: MessageBuilder,
original_type: Type) -> Optional[Type]:
"""original_type is the type of E in the expression E.var"""
node = itype.type.get(name)
if not node:
if itype.type.fallback_to_any:
return AnyType(TypeOfAny.special_form)
return None
is_decorated = isinstance(node.node, Decorator)
is_method = is_decorated or isinstance(node.node, FuncDef)
if is_lvalue:
if is_method:
msg.cant_assign_to_method(context)
if isinstance(node.node, TypeInfo):
msg.fail(messages.CANNOT_ASSIGN_TO_TYPE, context)
if itype.type.is_enum and not (is_lvalue or is_decorated or is_method):
return itype
t = node.type
if t:
if isinstance(t, PartialType):
symnode = node.node
assert symnode is not None
return handle_partial_attribute_type(t, is_lvalue, msg, symnode)
if not is_method and (isinstance(t, TypeVarType) or get_type_vars(t)):
msg.fail(messages.GENERIC_INSTANCE_VAR_CLASS_ACCESS, context)
is_classmethod = is_decorated and cast(Decorator,
node.node).func.is_class
return add_class_tvars(t, itype, is_classmethod, builtin_type,
original_type)
elif isinstance(node.node, Var):
not_ready_callback(name, context)
return AnyType(TypeOfAny.special_form)
if isinstance(node.node, TypeVarExpr):
msg.fail(
'Type variable "{}.{}" cannot be used as an expression'.format(
itype.type.name(), name), context)
return AnyType(TypeOfAny.from_error)
if isinstance(node.node, TypeInfo):
return type_object_type(node.node, builtin_type)
if isinstance(node.node, MypyFile):
# Reference to a module object.
return builtin_type('types.ModuleType')
if is_decorated:
# TODO: Return type of decorated function. This is quick hack to work around #998.
return AnyType(TypeOfAny.special_form)
else:
return function_type(cast(FuncBase, node.node),
builtin_type('builtins.function'))
def analyze_class_attribute_access(itype: Instance,
name: str,
context: Context,
is_lvalue: bool,
builtin_type: Callable[[str], Instance],
not_ready_callback: Callable[[str, Context], None],
msg: MessageBuilder,
original_type: Type) -> Optional[Type]:
"""original_type is the type of E in the expression E.var"""
node = itype.type.get(name)
if not node:
if itype.type.fallback_to_any:
return AnyType(TypeOfAny.special_form)
return None
is_decorated = isinstance(node.node, Decorator)
is_method = is_decorated or isinstance(node.node, FuncDef)
if is_lvalue:
if is_method:
msg.cant_assign_to_method(context)
if isinstance(node.node, TypeInfo):
msg.fail(messages.CANNOT_ASSIGN_TO_TYPE, context)
if itype.type.is_enum and not (is_lvalue or is_decorated or is_method):
return itype
t = node.type
if t:
if isinstance(t, PartialType):
symnode = node.node
assert symnode is not None
return handle_partial_attribute_type(t, is_lvalue, msg, symnode)
if not is_method and (isinstance(t, TypeVarType) or get_type_vars(t)):
msg.fail(messages.GENERIC_INSTANCE_VAR_CLASS_ACCESS, context)
is_classmethod = is_decorated and cast(Decorator, node.node).func.is_class
return add_class_tvars(t, itype, is_classmethod, builtin_type, original_type)
elif isinstance(node.node, Var):
not_ready_callback(name, context)
return AnyType(TypeOfAny.special_form)
if isinstance(node.node, TypeVarExpr):
msg.fail('Type variable "{}.{}" cannot be used as an expression'.format(
itype.type.name(), name), context)
return AnyType(TypeOfAny.from_error)
if isinstance(node.node, TypeInfo):
return type_object_type(node.node, builtin_type)
if isinstance(node.node, MypyFile):
# Reference to a module object.
return builtin_type('types.ModuleType')
if is_decorated:
# TODO: Return type of decorated function. This is quick hack to work around #998.
return AnyType(TypeOfAny.special_form)
else:
return function_type(cast(FuncBase, node.node), builtin_type('builtins.function'))
def analyze_class_attribute_access(itype: Instance, name: str,
mx: MemberContext) -> Optional[Type]:
"""original_type is the type of E in the expression E.var"""
node = itype.type.get(name)
if not node:
if itype.type.fallback_to_any:
return AnyType(TypeOfAny.special_form)
return None
is_decorated = isinstance(node.node, Decorator)
is_method = is_decorated or isinstance(node.node, FuncBase)
if mx.is_lvalue:
if is_method:
mx.msg.cant_assign_to_method(mx.context)
if isinstance(node.node, TypeInfo):
mx.msg.fail(message_registry.CANNOT_ASSIGN_TO_TYPE, mx.context)
# If a final attribute was declared on `self` in `__init__`, then it
# can't be accessed on the class object.
if node.implicit and isinstance(node.node, Var) and node.node.is_final:
mx.msg.fail(
message_registry.CANNOT_ACCESS_FINAL_INSTANCE_ATTR.format(
node.node.name()), mx.context)
# An assignment to final attribute on class object is also always an error,
# independently of types.
if mx.is_lvalue and not mx.chk.get_final_context():
check_final_member(name, itype.type, mx.msg, mx.context)
if itype.type.is_enum and not (mx.is_lvalue or is_decorated or is_method):
return itype
t = node.type
if t:
if isinstance(t, PartialType):
symnode = node.node
assert isinstance(symnode, Var)
return mx.chk.handle_partial_var_type(t, mx.is_lvalue, symnode,
mx.context)
# Find the class where method/variable was defined.
if isinstance(node.node, Decorator):
super_info = node.node.var.info # type: Optional[TypeInfo]
elif isinstance(node.node, (Var, SYMBOL_FUNCBASE_TYPES)):
super_info = node.node.info
else:
super_info = None
# Map the type to how it would look as a defining class. For example:
# class C(Generic[T]): ...
# class D(C[Tuple[T, S]]): ...
# D[int, str].method()
# Here itype is D[int, str], isuper is C[Tuple[int, str]].
if not super_info:
isuper = None
else:
isuper = map_instance_to_supertype(itype, super_info)
if isinstance(node.node, Var):
assert isuper is not None
# Check if original variable type has type variables. For example:
# class C(Generic[T]):
# x: T
# C.x # Error, ambiguous access
# C[int].x # Also an error, since C[int] is same as C at runtime
if isinstance(t, TypeVarType) or get_type_vars(t):
# Exception: access on Type[...], including first argument of class methods is OK.
if not isinstance(mx.original_type, TypeType):
mx.msg.fail(
message_registry.GENERIC_INSTANCE_VAR_CLASS_ACCESS,
mx.context)
# Erase non-mapped variables, but keep mapped ones, even if there is an error.
# In the above example this means that we infer following types:
# C.x -> Any
# C[int].x -> int
t = erase_typevars(expand_type_by_instance(t, isuper))
is_classmethod = (
(is_decorated and cast(Decorator, node.node).func.is_class)
or (isinstance(node.node, FuncBase) and node.node.is_class))
result = add_class_tvars(t, itype, isuper, is_classmethod,
mx.builtin_type, mx.original_type)
if not mx.is_lvalue:
result = analyze_descriptor_access(mx.original_type,
result,
mx.builtin_type,
mx.msg,
mx.context,
chk=mx.chk)
return result
elif isinstance(node.node, Var):
mx.not_ready_callback(name, mx.context)
return AnyType(TypeOfAny.special_form)
if isinstance(node.node, TypeVarExpr):
mx.msg.fail(
message_registry.CANNOT_USE_TYPEVAR_AS_EXPRESSION.format(
itype.type.name(), name), mx.context)
return AnyType(TypeOfAny.from_error)
if isinstance(node.node, TypeInfo):
return type_object_type(node.node, mx.builtin_type)
if isinstance(node.node, MypyFile):
# Reference to a module object.
return mx.builtin_type('types.ModuleType')
if isinstance(node.node, TypeAlias) and isinstance(node.node.target,
Instance):
return instance_alias_type(node.node, mx.builtin_type)
if is_decorated:
assert isinstance(node.node, Decorator)
if node.node.type:
return node.node.type
else:
mx.not_ready_callback(name, mx.context)
return AnyType(TypeOfAny.from_error)
else:
return function_type(cast(FuncBase, node.node),
mx.builtin_type('builtins.function'))
def visit_unbound_type(self, t: UnboundType) -> Type:
if t.optional:
t.optional = False
# We don't need to worry about double-wrapping Optionals or
# wrapping Anys: Union simplification will take care of that.
return make_optional_type(self.visit_unbound_type(t))
sym = self.lookup(t.name, t,
suppress_errors=self.third_pass) # type: ignore
if sym is not None:
if sym.node is None:
# UNBOUND_IMPORTED can happen if an unknown name was imported.
if sym.kind != UNBOUND_IMPORTED:
self.fail(errorcode.INTERNAL_ERROR_NODE_IS_NONE(sym.kind),
t)
return AnyType(TypeOfAny.special_form)
fullname = sym.node.fullname()
hook = self.plugin.get_type_analyze_hook(fullname)
if hook:
return hook(AnalyzeTypeContext(t, t, self))
if (fullname in nongen_builtins and t.args and not sym.normalized
and not self.allow_unnormalized):
self.fail(errorcode.NO_SUBSCRIPT_BUILTIN_ALIAS(fullname), t)
if self.tvar_scope:
tvar_def = self.tvar_scope.get_binding(sym)
else:
tvar_def = None
if self.warn_bound_tvar and sym.kind == TVAR and tvar_def is not None:
self.fail(
errorcode.
CANNOT_USE_BOUND_TYPE_VAR_TO_DEFINE_GENERIC_ALIAS(t.name),
t)
return AnyType(TypeOfAny.from_error)
elif sym.kind == TVAR and tvar_def is not None:
if len(t.args) > 0:
self.fail(errorcode.TYPE_VAR_USED_WITH_ARG(t.name), t)
return TypeVarType(tvar_def, t.line)
elif fullname == 'builtins.None':
return NoneTyp()
elif fullname == 'typing.Any' or fullname == 'builtins.Any':
return AnyType(TypeOfAny.explicit)
elif fullname == 'typing.Tuple':
if len(t.args) == 0 and not t.empty_tuple_index:
# Bare 'Tuple' is same as 'tuple'
if self.options.disallow_any_generics and not self.is_typeshed_stub:
self.fail(errorcode.BARE_GENERIC(), t)
typ = self.named_type('builtins.tuple',
line=t.line,
column=t.column)
typ.from_generic_builtin = True
return typ
if len(t.args) == 2 and isinstance(t.args[1], EllipsisType):
# Tuple[T, ...] (uniform, variable-length tuple)
instance = self.named_type('builtins.tuple',
[self.anal_type(t.args[0])])
instance.line = t.line
return instance
return self.tuple_type(self.anal_array(t.args))
elif fullname == 'typing.Union':
items = self.anal_array(t.args)
return UnionType.make_union(items)
elif fullname == 'typing.Optional':
if len(t.args) != 1:
self.fail(errorcode.OPTIONAL_MUST_HAVE_ONE_ARGUMENT(), t)
return AnyType(TypeOfAny.from_error)
item = self.anal_type(t.args[0])
return make_optional_type(item)
elif fullname == 'typing.Callable':
return self.analyze_callable_type(t)
elif fullname == 'typing.Type':
if len(t.args) == 0:
any_type = AnyType(TypeOfAny.from_omitted_generics,
line=t.line,
column=t.column)
return TypeType(any_type, line=t.line, column=t.column)
if len(t.args) != 1:
self.fail(errorcode.TYPE_MUST_HAVE_EXACTLY_ONE_TYPE(), t)
item = self.anal_type(t.args[0])
return TypeType.make_normalized(item, line=t.line)
elif fullname == 'typing.ClassVar':
if self.nesting_level > 0:
self.fail(
errorcode.INVALID_TYPE_CLASSVAR_NESTED_INSIDE_TYPE(),
t)
if len(t.args) == 0:
return AnyType(TypeOfAny.from_omitted_generics,
line=t.line,
column=t.column)
if len(t.args) != 1:
self.fail(
errorcode.CLASS_VAR_MUST_HAVE_AT_MOST_ONE_TYPE_ARG(),
t)
return AnyType(TypeOfAny.from_error)
item = self.anal_type(t.args[0])
if isinstance(item, TypeVarType) or get_type_vars(item):
self.fail(errorcode.CLASSVAR_CANNOT_BE_GENERIC(), t)
return AnyType(TypeOfAny.from_error)
return item
elif fullname in ('mypy_extensions.NoReturn', 'typing.NoReturn'):
return UninhabitedType(is_noreturn=True)
elif sym.kind == TYPE_ALIAS:
override = sym.type_override
all_vars = sym.alias_tvars
assert override is not None
an_args = self.anal_array(t.args)
if all_vars is not None:
exp_len = len(all_vars)
else:
exp_len = 0
act_len = len(an_args)
if exp_len > 0 and act_len == 0:
# Interpret bare Alias same as normal generic, i.e., Alias[Any, Any, ...]
assert all_vars is not None
return set_any_tvars(override, all_vars, t.line, t.column)
if exp_len == 0 and act_len == 0:
return override
if act_len != exp_len:
self.fail(
errorcode.BAD_NUMBER_ARGUMENT_FOR_TYPEALIAS(
exp_len, act_len), t)
return set_any_tvars(override,
all_vars or [],
t.line,
t.column,
implicit=False)
assert all_vars is not None
return replace_alias_tvars(override, all_vars, an_args, t.line,
t.column)
elif not isinstance(sym.node, TypeInfo):
name = sym.fullname
if name is None:
name = sym.node.name()
if isinstance(sym.node, Var) and isinstance(
sym.node.type, AnyType):
# Something with an Any type -- make it an alias for Any in a type
# context. This is slightly problematic as it allows using the type 'Any'
# as a base class -- however, this will fail soon at runtime so the problem
# is pretty minor.
return AnyType(TypeOfAny.from_unimported_type)
# Allow unbound type variables when defining an alias
if not (self.aliasing and sym.kind == TVAR and
(not self.tvar_scope
or self.tvar_scope.get_binding(sym) is None)):
if (not self.third_pass and not self.in_dynamic_func
and not (isinstance(sym.node, (FuncDef, Decorator))
or isinstance(sym.node, Var)
and sym.node.is_ready)
and not (sym.kind == TVAR and tvar_def is None)):
if t.args and not self.global_scope:
self.fail(
errorcode.UNSUPPORTED_FORWARD_REFERENCE(
t.name), t)
return AnyType(TypeOfAny.from_error)
return ForwardRef(t)
self.fail(errorcode.INVALID_TYPE_X(name), t)
if self.third_pass and sym.kind == TVAR:
self.note_func(
errorcode.FORWARD_REERENCES_TO_TYPE_VAR_PROHIBITED(
), t)
return t
info = sym.node # type: TypeInfo
if len(t.args) > 0 and info.fullname() == 'builtins.tuple':
fallback = Instance(info, [AnyType(TypeOfAny.special_form)],
t.line)
return TupleType(self.anal_array(t.args), fallback, t.line)
else:
# Analyze arguments and construct Instance type. The
# number of type arguments and their values are
# checked only later, since we do not always know the
# valid count at this point. Thus we may construct an
# Instance with an invalid number of type arguments.
instance = Instance(info, self.anal_array(t.args), t.line,
t.column)
instance.from_generic_builtin = sym.normalized
tup = info.tuple_type
if tup is not None:
# The class has a Tuple[...] base class so it will be
# represented as a tuple type.
if t.args:
self.fail(
errorcode.GENERIC_TUPLE_TYPES_NOT_SUPPORTED(), t)
return AnyType(TypeOfAny.from_error)
return tup.copy_modified(items=self.anal_array(tup.items),
fallback=instance)
td = info.typeddict_type
if td is not None:
# The class has a TypedDict[...] base class so it will be
# represented as a typeddict type.
if t.args:
self.fail(
errorcode.GENERIC_TYPEDDICT_TYPES_NOT_SUPPORTED(),
t)
return AnyType(TypeOfAny.from_error)
# Create a named TypedDictType
return td.copy_modified(item_types=self.anal_array(
list(td.items.values())),
fallback=instance)
return instance
else:
if self.third_pass:
self.fail(errorcode.INVALID_TYPE_X(t.name), t)
return AnyType(TypeOfAny.from_error)
return AnyType(TypeOfAny.special_form)
def visit_unbound_type(self, t: UnboundType) -> Type:
if t.optional:
t.optional = False
# We don't need to worry about double-wrapping Optionals or
# wrapping Anys: Union simplification will take care of that.
return make_optional_type(self.visit_unbound_type(t))
sym = self.lookup(t.name, t)
if sym is not None:
if sym.node is None:
# UNBOUND_IMPORTED can happen if an unknown name was imported.
if sym.kind != UNBOUND_IMPORTED:
self.fail(
'Internal error (node is None, kind={})'.format(
sym.kind), t)
return AnyType()
fullname = sym.node.fullname()
hook = self.plugin.get_type_analyze_hook(fullname)
if hook:
return hook(AnalyzeTypeContext(t, t, self))
if (fullname in nongen_builtins and t.args and not sym.normalized
and not self.allow_unnormalized):
self.fail(no_subscript_builtin_alias(fullname), t)
tvar_def = self.tvar_scope.get_binding(sym)
if sym.kind == TVAR and tvar_def is not None:
if len(t.args) > 0:
self.fail(
'Type variable "{}" used with arguments'.format(
t.name), t)
return TypeVarType(tvar_def, t.line)
elif fullname == 'builtins.None':
return NoneTyp()
elif fullname == 'typing.Any' or fullname == 'builtins.Any':
return AnyType(explicit=True)
elif fullname == 'typing.Tuple':
if len(t.args) == 0 and not t.empty_tuple_index:
# Bare 'Tuple' is same as 'tuple'
if 'generics' in self.options.disallow_any and not self.is_typeshed_stub:
self.fail(messages.BARE_GENERIC, t)
typ = self.named_type('builtins.tuple',
line=t.line,
column=t.column)
typ.from_generic_builtin = True
return typ
if len(t.args) == 2 and isinstance(t.args[1], EllipsisType):
# Tuple[T, ...] (uniform, variable-length tuple)
instance = self.named_type('builtins.tuple',
[self.anal_type(t.args[0])])
instance.line = t.line
return instance
return self.tuple_type(self.anal_array(t.args))
elif fullname == 'typing.Union':
items = self.anal_array(t.args)
return UnionType.make_union(items)
elif fullname == 'typing.Optional':
if len(t.args) != 1:
self.fail(
'Optional[...] must have exactly one type argument', t)
return AnyType()
item = self.anal_type(t.args[0])
return make_optional_type(item)
elif fullname == 'typing.Callable':
return self.analyze_callable_type(t)
elif fullname == 'typing.Type':
if len(t.args) == 0:
any_type = AnyType(from_omitted_generics=True,
line=t.line,
column=t.column)
return TypeType(any_type, line=t.line, column=t.column)
if len(t.args) != 1:
self.fail('Type[...] must have exactly one type argument',
t)
item = self.anal_type(t.args[0])
return TypeType.make_normalized(item, line=t.line)
elif fullname == 'typing.ClassVar':
if self.nesting_level > 0:
self.fail(
'Invalid type: ClassVar nested inside other type', t)
if len(t.args) == 0:
return AnyType(line=t.line)
if len(t.args) != 1:
self.fail(
'ClassVar[...] must have at most one type argument', t)
return AnyType()
item = self.anal_type(t.args[0])
if isinstance(item, TypeVarType) or get_type_vars(item):
self.fail('Invalid type: ClassVar cannot be generic', t)
return AnyType()
return item
elif fullname in ('mypy_extensions.NoReturn', 'typing.NoReturn'):
return UninhabitedType(is_noreturn=True)
elif sym.kind == TYPE_ALIAS:
override = sym.type_override
all_vars = sym.alias_tvars
assert override is not None
an_args = self.anal_array(t.args)
if all_vars is not None:
exp_len = len(all_vars)
else:
exp_len = 0
act_len = len(an_args)
if exp_len > 0 and act_len == 0:
# Interpret bare Alias same as normal generic, i.e., Alias[Any, Any, ...]
assert all_vars is not None
return set_any_tvars(override, all_vars, t.line, t.column)
if exp_len == 0 and act_len == 0:
return override
if act_len != exp_len:
self.fail(
'Bad number of arguments for type alias, expected: %s, given: %s'
% (exp_len, act_len), t)
return set_any_tvars(override,
all_vars or [],
t.line,
t.column,
implicit=False)
assert all_vars is not None
return replace_alias_tvars(override, all_vars, an_args, t.line,
t.column)
elif not isinstance(sym.node, TypeInfo):
name = sym.fullname
if name is None:
name = sym.node.name()
if isinstance(sym.node, Var) and isinstance(
sym.node.type, AnyType):
# Something with an Any type -- make it an alias for Any in a type
# context. This is slightly problematic as it allows using the type 'Any'
# as a base class -- however, this will fail soon at runtime so the problem
# is pretty minor.
return AnyType(from_unimported_type=True)
# Allow unbound type variables when defining an alias
if not (self.aliasing and sym.kind == TVAR
and self.tvar_scope.get_binding(sym) is None):
self.fail('Invalid type "{}"'.format(name), t)
return t
info = sym.node # type: TypeInfo
if len(t.args) > 0 and info.fullname() == 'builtins.tuple':
return TupleType(self.anal_array(t.args),
Instance(info, [AnyType()], t.line), t.line)
else:
# Analyze arguments and construct Instance type. The
# number of type arguments and their values are
# checked only later, since we do not always know the
# valid count at this point. Thus we may construct an
# Instance with an invalid number of type arguments.
instance = Instance(info, self.anal_array(t.args), t.line,
t.column)
instance.from_generic_builtin = sym.normalized
tup = info.tuple_type
if tup is not None:
# The class has a Tuple[...] base class so it will be
# represented as a tuple type.
if t.args:
self.fail('Generic tuple types not supported', t)
return AnyType()
return tup.copy_modified(items=self.anal_array(tup.items),
fallback=instance)
td = info.typeddict_type
if td is not None:
# The class has a TypedDict[...] base class so it will be
# represented as a typeddict type.
if t.args:
self.fail('Generic TypedDict types not supported', t)
return AnyType()
# Create a named TypedDictType
return td.copy_modified(item_types=self.anal_array(
list(td.items.values())),
fallback=instance)
return instance
else:
return AnyType()
def analyze_class_attribute_access(itype: Instance, name: str,
mx: MemberContext) -> Optional[Type]:
"""original_type is the type of E in the expression E.var"""
node = itype.type.get(name)
if not node:
if itype.type.fallback_to_any:
return AnyType(TypeOfAny.special_form)
return None
is_decorated = isinstance(node.node, Decorator)
is_method = is_decorated or isinstance(node.node, FuncBase)
if mx.is_lvalue:
if is_method:
mx.msg.cant_assign_to_method(mx.context)
if isinstance(node.node, TypeInfo):
mx.msg.fail(messages.CANNOT_ASSIGN_TO_TYPE, mx.context)
# If a final attribute was declared on `self` in `__init__`, then it
# can't be accessed on the class object.
if node.implicit and isinstance(node.node, Var) and node.node.is_final:
mx.msg.fail(
messages.CANNOT_ACCESS_FINAL_INSTANCE_ATTR.format(
node.node.name()), mx.context)
# An assignment to final attribute on class object is also always an error,
# independently of types.
if mx.is_lvalue and not mx.chk.get_final_context():
check_final_member(name, itype.type, mx.msg, mx.context)
if itype.type.is_enum and not (mx.is_lvalue or is_decorated or is_method):
return itype
t = node.type
if t:
if isinstance(t, PartialType):
symnode = node.node
assert isinstance(symnode, Var)
return mx.chk.handle_partial_var_type(t, mx.is_lvalue, symnode,
mx.context)
if not is_method and (isinstance(t, TypeVarType) or get_type_vars(t)):
mx.msg.fail(messages.GENERIC_INSTANCE_VAR_CLASS_ACCESS, mx.context)
is_classmethod = (
(is_decorated and cast(Decorator, node.node).func.is_class)
or (isinstance(node.node, FuncBase) and node.node.is_class))
result = add_class_tvars(t, itype, is_classmethod, mx.builtin_type,
mx.original_type)
if not mx.is_lvalue:
result = analyze_descriptor_access(mx.original_type,
result,
mx.builtin_type,
mx.msg,
mx.context,
chk=mx.chk)
return result
elif isinstance(node.node, Var):
mx.not_ready_callback(name, mx.context)
return AnyType(TypeOfAny.special_form)
if isinstance(node.node, TypeVarExpr):
mx.msg.fail(
messages.CANNOT_USE_TYPEVAR_AS_EXPRESSION.format(
itype.type.name(), name), mx.context)
return AnyType(TypeOfAny.from_error)
if isinstance(node.node, TypeInfo):
return type_object_type(node.node, mx.builtin_type)
if isinstance(node.node, MypyFile):
# Reference to a module object.
return mx.builtin_type('types.ModuleType')
if isinstance(node.node, TypeAlias) and isinstance(node.node.target,
Instance):
return instance_alias_type(node.node, mx.builtin_type)
if is_decorated:
assert isinstance(node.node, Decorator)
if node.node.type:
return node.node.type
else:
mx.not_ready_callback(name, mx.context)
return AnyType(TypeOfAny.from_error)
else:
return function_type(cast(FuncBase, node.node),
mx.builtin_type('builtins.function'))
def analyze_class_attribute_access(itype: Instance,
name: str,
context: Context,
is_lvalue: bool,
builtin_type: Callable[[str], Instance],
not_ready_callback: Callable[[str, Context], None],
msg: MessageBuilder,
original_type: Type,
chk: 'mypy.checker.TypeChecker') -> Optional[Type]:
"""original_type is the type of E in the expression E.var"""
node = itype.type.get(name)
if not node:
if itype.type.fallback_to_any:
return AnyType(TypeOfAny.special_form)
return None
is_decorated = isinstance(node.node, Decorator)
is_method = is_decorated or isinstance(node.node, FuncBase)
if is_lvalue:
if is_method:
msg.cant_assign_to_method(context)
if isinstance(node.node, TypeInfo):
msg.fail(messages.CANNOT_ASSIGN_TO_TYPE, context)
# If a final attribute was declared on `self` in `__init__`, then it
# can't be accessed on the class object.
if node.implicit and isinstance(node.node, Var) and node.node.is_final:
msg.fail('Cannot access final instance '
'attribute "{}" on class object'.format(node.node.name()), context)
# An assignment to final attribute on class object is also always an error,
# independently of types.
if is_lvalue and not chk.get_final_context():
check_final_member(name, itype.type, msg, context)
if itype.type.is_enum and not (is_lvalue or is_decorated or is_method):
return itype
t = node.type
if t:
if isinstance(t, PartialType):
symnode = node.node
assert isinstance(symnode, Var)
return chk.handle_partial_var_type(t, is_lvalue, symnode, context)
if not is_method and (isinstance(t, TypeVarType) or get_type_vars(t)):
msg.fail(messages.GENERIC_INSTANCE_VAR_CLASS_ACCESS, context)
is_classmethod = ((is_decorated and cast(Decorator, node.node).func.is_class)
or (isinstance(node.node, FuncBase) and node.node.is_class))
result = add_class_tvars(t, itype, is_classmethod, builtin_type, original_type)
if not is_lvalue:
result = analyze_descriptor_access(original_type, result, builtin_type,
msg, context, chk=chk)
return result
elif isinstance(node.node, Var):
not_ready_callback(name, context)
return AnyType(TypeOfAny.special_form)
if isinstance(node.node, TypeVarExpr):
msg.fail('Type variable "{}.{}" cannot be used as an expression'.format(
itype.type.name(), name), context)
return AnyType(TypeOfAny.from_error)
if isinstance(node.node, TypeInfo):
return type_object_type(node.node, builtin_type)
if isinstance(node.node, MypyFile):
# Reference to a module object.
return builtin_type('types.ModuleType')
if isinstance(node.node, TypeAlias) and isinstance(node.node.target, Instance):
return instance_alias_type(node.node, builtin_type)
if is_decorated:
assert isinstance(node.node, Decorator)
if node.node.type:
return node.node.type
else:
not_ready_callback(name, context)
return AnyType(TypeOfAny.from_error)
else:
return function_type(cast(FuncBase, node.node), builtin_type('builtins.function'))
def try_analyze_special_unbound_type(self, t: UnboundType, fullname: str) -> Optional[Type]:
"""Bind special type that is recognized through magic name such as 'typing.Any'.
Return the bound type if successful, and return None if the type is a normal type.
"""
if fullname == 'builtins.None':
return NoneType()
elif fullname == 'typing.Any' or fullname == 'builtins.Any':
return AnyType(TypeOfAny.explicit)
elif fullname in ('typing.Final', 'typing_extensions.Final'):
self.fail("Final can be only used as an outermost qualifier"
" in a variable annotation", t)
return AnyType(TypeOfAny.from_error)
elif fullname == 'typing.Tuple':
# Tuple is special because it is involved in builtin import cycle
# and may be not ready when used.
sym = self.api.lookup_fully_qualified_or_none('builtins.tuple')
if not sym or isinstance(sym.node, PlaceholderNode):
if self.api.is_incomplete_namespace('builtins'):
self.api.record_incomplete_ref()
else:
self.fail("Name 'tuple' is not defined", t)
return AnyType(TypeOfAny.special_form)
if len(t.args) == 0 and not t.empty_tuple_index:
# Bare 'Tuple' is same as 'tuple'
if self.options.disallow_any_generics and not self.is_typeshed_stub:
self.fail(message_registry.BARE_GENERIC, t)
return self.named_type('builtins.tuple', line=t.line, column=t.column)
if len(t.args) == 2 and isinstance(t.args[1], EllipsisType):
# Tuple[T, ...] (uniform, variable-length tuple)
instance = self.named_type('builtins.tuple', [self.anal_type(t.args[0])])
instance.line = t.line
return instance
return self.tuple_type(self.anal_array(t.args))
elif fullname == 'typing.Union':
items = self.anal_array(t.args)
return UnionType.make_union(items)
elif fullname == 'typing.Optional':
if len(t.args) != 1:
self.fail('Optional[...] must have exactly one type argument', t)
return AnyType(TypeOfAny.from_error)
item = self.anal_type(t.args[0])
return make_optional_type(item)
elif fullname == 'typing.Callable':
return self.analyze_callable_type(t)
elif fullname == 'typing.Type':
if len(t.args) == 0:
any_type = AnyType(TypeOfAny.from_omitted_generics,
line=t.line, column=t.column)
return TypeType(any_type, line=t.line, column=t.column)
if len(t.args) != 1:
self.fail('Type[...] must have exactly one type argument', t)
item = self.anal_type(t.args[0])
return TypeType.make_normalized(item, line=t.line)
elif fullname == 'typing.ClassVar':
if self.nesting_level > 0:
self.fail('Invalid type: ClassVar nested inside other type', t)
if len(t.args) == 0:
return AnyType(TypeOfAny.from_omitted_generics, line=t.line, column=t.column)
if len(t.args) != 1:
self.fail('ClassVar[...] must have at most one type argument', t)
return AnyType(TypeOfAny.from_error)
item = self.anal_type(t.args[0])
if isinstance(item, TypeVarType) or get_type_vars(item):
self.fail('Invalid type: ClassVar cannot be generic', t)
return AnyType(TypeOfAny.from_error)
return item
elif fullname in ('mypy_extensions.NoReturn', 'typing.NoReturn'):
return UninhabitedType(is_noreturn=True)
elif fullname in ('typing_extensions.Literal', 'typing.Literal'):
return self.analyze_literal_type(t)
return None
def analyze_class_attribute_access(itype: Instance,
name: str,
mx: MemberContext) -> Optional[Type]:
"""original_type is the type of E in the expression E.var"""
node = itype.type.get(name)
if not node:
if itype.type.fallback_to_any:
return AnyType(TypeOfAny.special_form)
return None
is_decorated = isinstance(node.node, Decorator)
is_method = is_decorated or isinstance(node.node, FuncBase)
if mx.is_lvalue:
if is_method:
mx.msg.cant_assign_to_method(mx.context)
if isinstance(node.node, TypeInfo):
mx.msg.fail(message_registry.CANNOT_ASSIGN_TO_TYPE, mx.context)
# If a final attribute was declared on `self` in `__init__`, then it
# can't be accessed on the class object.
if node.implicit and isinstance(node.node, Var) and node.node.is_final:
mx.msg.fail(message_registry.CANNOT_ACCESS_FINAL_INSTANCE_ATTR
.format(node.node.name()), mx.context)
# An assignment to final attribute on class object is also always an error,
# independently of types.
if mx.is_lvalue and not mx.chk.get_final_context():
check_final_member(name, itype.type, mx.msg, mx.context)
if itype.type.is_enum and not (mx.is_lvalue or is_decorated or is_method):
return itype
t = node.type
if t:
if isinstance(t, PartialType):
symnode = node.node
assert isinstance(symnode, Var)
return mx.chk.handle_partial_var_type(t, mx.is_lvalue, symnode, mx.context)
# Find the class where method/variable was defined.
if isinstance(node.node, Decorator):
super_info = node.node.var.info # type: Optional[TypeInfo]
elif isinstance(node.node, (Var, SYMBOL_FUNCBASE_TYPES)):
super_info = node.node.info
else:
super_info = None
# Map the type to how it would look as a defining class. For example:
# class C(Generic[T]): ...
# class D(C[Tuple[T, S]]): ...
# D[int, str].method()
# Here itype is D[int, str], isuper is C[Tuple[int, str]].
if not super_info:
isuper = None
else:
isuper = map_instance_to_supertype(itype, super_info)
if isinstance(node.node, Var):
assert isuper is not None
# Check if original variable type has type variables. For example:
# class C(Generic[T]):
# x: T
# C.x # Error, ambiguous access
# C[int].x # Also an error, since C[int] is same as C at runtime
if isinstance(t, TypeVarType) or get_type_vars(t):
# Exception: access on Type[...], including first argument of class methods is OK.
if not isinstance(mx.original_type, TypeType):
mx.msg.fail(message_registry.GENERIC_INSTANCE_VAR_CLASS_ACCESS, mx.context)
# Erase non-mapped variables, but keep mapped ones, even if there is an error.
# In the above example this means that we infer following types:
# C.x -> Any
# C[int].x -> int
t = erase_typevars(expand_type_by_instance(t, isuper))
is_classmethod = ((is_decorated and cast(Decorator, node.node).func.is_class)
or (isinstance(node.node, FuncBase) and node.node.is_class))
result = add_class_tvars(t, itype, isuper, is_classmethod, mx.builtin_type,
mx.original_type)
if not mx.is_lvalue:
result = analyze_descriptor_access(mx.original_type, result, mx.builtin_type,
mx.msg, mx.context, chk=mx.chk)
return result
elif isinstance(node.node, Var):
mx.not_ready_callback(name, mx.context)
return AnyType(TypeOfAny.special_form)
if isinstance(node.node, TypeVarExpr):
mx.msg.fail(message_registry.CANNOT_USE_TYPEVAR_AS_EXPRESSION.format(
itype.type.name(), name), mx.context)
return AnyType(TypeOfAny.from_error)
if isinstance(node.node, TypeInfo):
return type_object_type(node.node, mx.builtin_type)
if isinstance(node.node, MypyFile):
# Reference to a module object.
return mx.builtin_type('types.ModuleType')
if isinstance(node.node, TypeAlias) and isinstance(node.node.target, Instance):
return instance_alias_type(node.node, mx.builtin_type)
if is_decorated:
assert isinstance(node.node, Decorator)
if node.node.type:
return node.node.type
else:
mx.not_ready_callback(name, mx.context)
return AnyType(TypeOfAny.from_error)
else:
return function_type(cast(FuncBase, node.node), mx.builtin_type('builtins.function'))
def visit_unbound_type_nonoptional(self, t: UnboundType) -> Type:
sym = self.lookup(t.name, t, suppress_errors=self.third_pass)
if '.' in t.name:
# Handle indirect references to imported names.
#
# TODO: Do this for module-local references as well and remove ImportedName
# type check below.
sym = self.api.dereference_module_cross_ref(sym)
if sym is not None:
if isinstance(sym.node, ImportedName):
# Forward reference to an imported name that hasn't been processed yet.
# To maintain backward compatibility, these get translated to Any.
#
# TODO: Remove this special case.
return AnyType(TypeOfAny.implementation_artifact)
if sym.fullname in type_aliases:
# Resolve forward reference to type alias like 'typing.List'.
# TODO: Unify how type aliases are handled; currently we resolve them in two
# places (the other is in the semantic analyzer pass 2).
resolved = type_aliases[sym.fullname]
new = self.api.lookup_qualified(resolved, t)
if new:
sym = new.copy()
sym.normalized = True
if sym.node is None:
# UNBOUND_IMPORTED can happen if an unknown name was imported.
if sym.kind != UNBOUND_IMPORTED:
self.fail(
'Internal error (node is None, kind={})'.format(
sym.kind), t)
return AnyType(TypeOfAny.special_form)
fullname = sym.node.fullname()
hook = self.plugin.get_type_analyze_hook(fullname)
if hook:
return hook(AnalyzeTypeContext(t, t, self))
if (fullname in nongen_builtins and t.args and not sym.normalized
and not self.allow_unnormalized):
self.fail(no_subscript_builtin_alias(fullname), t)
if self.tvar_scope:
tvar_def = self.tvar_scope.get_binding(sym)
else:
tvar_def = None
if self.warn_bound_tvar and sym.kind == TVAR and tvar_def is not None:
self.fail(
'Can\'t use bound type variable "{}"'
' to define generic alias'.format(t.name), t)
return AnyType(TypeOfAny.from_error)
elif sym.kind == TVAR and tvar_def is not None:
if len(t.args) > 0:
self.fail(
'Type variable "{}" used with arguments'.format(
t.name), t)
return TypeVarType(tvar_def, t.line)
elif fullname == 'builtins.None':
return NoneTyp()
elif fullname == 'typing.Any' or fullname == 'builtins.Any':
return AnyType(TypeOfAny.explicit)
elif fullname == 'typing.Tuple':
if len(t.args) == 0 and not t.empty_tuple_index:
# Bare 'Tuple' is same as 'tuple'
if self.options.disallow_any_generics and not self.is_typeshed_stub:
self.fail(messages.BARE_GENERIC, t)
typ = self.named_type('builtins.tuple',
line=t.line,
column=t.column)
typ.from_generic_builtin = True
return typ
if len(t.args) == 2 and isinstance(t.args[1], EllipsisType):
# Tuple[T, ...] (uniform, variable-length tuple)
instance = self.named_type('builtins.tuple',
[self.anal_type(t.args[0])])
instance.line = t.line
return instance
return self.tuple_type(self.anal_array(t.args))
elif fullname == 'typing.Union':
items = self.anal_array(t.args)
return UnionType.make_union(items)
elif fullname == 'typing.Optional':
if len(t.args) != 1:
self.fail(
'Optional[...] must have exactly one type argument', t)
return AnyType(TypeOfAny.from_error)
item = self.anal_type(t.args[0])
return make_optional_type(item)
elif fullname == 'typing.Callable':
return self.analyze_callable_type(t)
elif fullname == 'typing.Type':
if len(t.args) == 0:
any_type = AnyType(TypeOfAny.from_omitted_generics,
line=t.line,
column=t.column)
return TypeType(any_type, line=t.line, column=t.column)
if len(t.args) != 1:
self.fail('Type[...] must have exactly one type argument',
t)
item = self.anal_type(t.args[0])
return TypeType.make_normalized(item, line=t.line)
elif fullname == 'typing.ClassVar':
if self.nesting_level > 0:
self.fail(
'Invalid type: ClassVar nested inside other type', t)
if len(t.args) == 0:
return AnyType(TypeOfAny.from_omitted_generics,
line=t.line,
column=t.column)
if len(t.args) != 1:
self.fail(
'ClassVar[...] must have at most one type argument', t)
return AnyType(TypeOfAny.from_error)
item = self.anal_type(t.args[0])
if isinstance(item, TypeVarType) or get_type_vars(item):
self.fail('Invalid type: ClassVar cannot be generic', t)
return AnyType(TypeOfAny.from_error)
return item
elif fullname in ('mypy_extensions.NoReturn', 'typing.NoReturn'):
return UninhabitedType(is_noreturn=True)
elif sym.kind == TYPE_ALIAS:
if sym.alias_name is not None:
self.aliases_used.add(sym.alias_name)
override = sym.type_override
all_vars = sym.alias_tvars
assert override is not None
an_args = self.anal_array(t.args)
if all_vars is not None:
exp_len = len(all_vars)
else:
exp_len = 0
act_len = len(an_args)
if exp_len > 0 and act_len == 0:
# Interpret bare Alias same as normal generic, i.e., Alias[Any, Any, ...]
assert all_vars is not None
return set_any_tvars(override, all_vars, t.line, t.column)
if exp_len == 0 and act_len == 0:
return override
if act_len != exp_len:
self.fail(
'Bad number of arguments for type alias, expected: %s, given: %s'
% (exp_len, act_len), t)
return set_any_tvars(override,
all_vars or [],
t.line,
t.column,
implicit=False)
assert all_vars is not None
return replace_alias_tvars(override, all_vars, an_args, t.line,
t.column)
elif not isinstance(sym.node, TypeInfo):
name = sym.fullname
if name is None:
name = sym.node.name()
if isinstance(sym.node, Var) and isinstance(
sym.node.type, AnyType):
# Something with an Any type -- make it an alias for Any in a type
# context. This is slightly problematic as it allows using the type 'Any'
# as a base class -- however, this will fail soon at runtime so the problem
# is pretty minor.
return AnyType(
TypeOfAny.from_unimported_type,
missing_import_name=sym.node.type.missing_import_name)
# Allow unbound type variables when defining an alias
if not (self.aliasing and sym.kind == TVAR and
(not self.tvar_scope
or self.tvar_scope.get_binding(sym) is None)):
if (not self.third_pass and not self.in_dynamic_func
and not (isinstance(sym.node, (FuncDef, Decorator))
or isinstance(sym.node, Var)
and sym.node.is_ready)
and not (sym.kind == TVAR and tvar_def is None)):
if t.args and not self.global_scope:
self.fail(
'Unsupported forward reference to "{}"'.format(
t.name), t)
return AnyType(TypeOfAny.from_error)
return ForwardRef(t)
self.fail('Invalid type "{}"'.format(name), t)
if self.third_pass and sym.kind == TVAR:
self.note_func(
"Forward references to type variables are prohibited",
t)
return t
info = sym.node # type: TypeInfo
if sym.is_aliasing:
if sym.alias_name is not None:
self.aliases_used.add(sym.alias_name)
if len(t.args) > 0 and info.fullname() == 'builtins.tuple':
fallback = Instance(info, [AnyType(TypeOfAny.special_form)],
t.line)
return TupleType(self.anal_array(t.args), fallback, t.line)
else:
# Analyze arguments and construct Instance type. The
# number of type arguments and their values are
# checked only later, since we do not always know the
# valid count at this point. Thus we may construct an
# Instance with an invalid number of type arguments.
instance = Instance(info, self.anal_array(t.args), t.line,
t.column)
instance.from_generic_builtin = sym.normalized
tup = info.tuple_type
if tup is not None:
# The class has a Tuple[...] base class so it will be
# represented as a tuple type.
if t.args:
self.fail('Generic tuple types not supported', t)
return AnyType(TypeOfAny.from_error)
return tup.copy_modified(items=self.anal_array(tup.items),
fallback=instance)
td = info.typeddict_type
if td is not None:
# The class has a TypedDict[...] base class so it will be
# represented as a typeddict type.
if t.args:
self.fail('Generic TypedDict types not supported', t)
return AnyType(TypeOfAny.from_error)
# Create a named TypedDictType
return td.copy_modified(item_types=self.anal_array(
list(td.items.values())),
fallback=instance)
return instance
else:
if self.third_pass:
self.fail('Invalid type "{}"'.format(t.name), t)
return AnyType(TypeOfAny.from_error)
return AnyType(TypeOfAny.special_form)
def visit_unbound_type_nonoptional(self, t: UnboundType) -> Type:
sym = self.lookup(t.name, t, suppress_errors=self.third_pass)
if '.' in t.name:
# Handle indirect references to imported names.
#
# TODO: Do this for module-local references as well and remove ImportedName
# type check below.
sym = self.api.dereference_module_cross_ref(sym)
if sym is not None:
if isinstance(sym.node, ImportedName):
# Forward reference to an imported name that hasn't been processed yet.
# To maintain backward compatibility, these get translated to Any.
#
# TODO: Remove this special case.
return AnyType(TypeOfAny.implementation_artifact)
if sym.node is None:
# UNBOUND_IMPORTED can happen if an unknown name was imported.
if sym.kind != UNBOUND_IMPORTED:
self.fail(
'Internal error (node is None, kind={})'.format(
sym.kind), t)
return AnyType(TypeOfAny.special_form)
fullname = sym.node.fullname()
hook = self.plugin.get_type_analyze_hook(fullname)
if hook:
return hook(AnalyzeTypeContext(t, t, self))
if (fullname in nongen_builtins and t.args
and not self.allow_unnormalized):
self.fail(
no_subscript_builtin_alias(
fullname, propose_alt=not self.defining_alias), t)
if self.tvar_scope:
tvar_def = self.tvar_scope.get_binding(sym)
else:
tvar_def = None
if sym.kind == TVAR and tvar_def is not None and self.defining_alias:
self.fail(
'Can\'t use bound type variable "{}"'
' to define generic alias'.format(t.name), t)
return AnyType(TypeOfAny.from_error)
elif sym.kind == TVAR and tvar_def is not None:
if len(t.args) > 0:
self.fail(
'Type variable "{}" used with arguments'.format(
t.name), t)
return TypeVarType(tvar_def, t.line)
elif fullname == 'builtins.None':
return NoneTyp()
elif fullname == 'typing.Any' or fullname == 'builtins.Any':
return AnyType(TypeOfAny.explicit)
elif fullname in ('typing.Final', 'typing_extensions.Final'):
self.fail(
"Final can be only used as an outermost qualifier"
" in a variable annotation", t)
return AnyType(TypeOfAny.from_error)
elif fullname == 'typing.Tuple':
if len(t.args) == 0 and not t.empty_tuple_index:
# Bare 'Tuple' is same as 'tuple'
if self.options.disallow_any_generics and not self.is_typeshed_stub:
self.fail(messages.BARE_GENERIC, t)
return self.named_type('builtins.tuple',
line=t.line,
column=t.column)
if len(t.args) == 2 and isinstance(t.args[1], EllipsisType):
# Tuple[T, ...] (uniform, variable-length tuple)
instance = self.named_type('builtins.tuple',
[self.anal_type(t.args[0])])
instance.line = t.line
return instance
return self.tuple_type(self.anal_array(t.args))
elif fullname == 'typing.Union':
items = self.anal_array(t.args)
return UnionType.make_union(items)
elif fullname == 'typing.Optional':
if len(t.args) != 1:
self.fail(
'Optional[...] must have exactly one type argument', t)
return AnyType(TypeOfAny.from_error)
item = self.anal_type(t.args[0])
return make_optional_type(item)
elif fullname == 'typing.Callable':
return self.analyze_callable_type(t)
elif fullname == 'typing.Type':
if len(t.args) == 0:
any_type = AnyType(TypeOfAny.from_omitted_generics,
line=t.line,
column=t.column)
return TypeType(any_type, line=t.line, column=t.column)
if len(t.args) != 1:
self.fail('Type[...] must have exactly one type argument',
t)
item = self.anal_type(t.args[0])
return TypeType.make_normalized(item, line=t.line)
elif fullname == 'typing.ClassVar':
if self.nesting_level > 0:
self.fail(
'Invalid type: ClassVar nested inside other type', t)
if len(t.args) == 0:
return AnyType(TypeOfAny.from_omitted_generics,
line=t.line,
column=t.column)
if len(t.args) != 1:
self.fail(
'ClassVar[...] must have at most one type argument', t)
return AnyType(TypeOfAny.from_error)
item = self.anal_type(t.args[0])
if isinstance(item, TypeVarType) or get_type_vars(item):
self.fail('Invalid type: ClassVar cannot be generic', t)
return AnyType(TypeOfAny.from_error)
return item
elif fullname in ('mypy_extensions.NoReturn', 'typing.NoReturn'):
return UninhabitedType(is_noreturn=True)
elif isinstance(sym.node, TypeAlias):
self.aliases_used.add(sym.node.fullname())
all_vars = sym.node.alias_tvars
target = sym.node.target
an_args = self.anal_array(t.args)
return expand_type_alias(target, all_vars, an_args, self.fail,
sym.node.no_args, t)
elif not isinstance(sym.node, TypeInfo):
# Something unusual. We try our best to find out what it is.
name = sym.fullname
if name is None:
name = sym.node.name()
# Option 1:
# Something with an Any type -- make it an alias for Any in a type
# context. This is slightly problematic as it allows using the type 'Any'
# as a base class -- however, this will fail soon at runtime so the problem
# is pretty minor.
if isinstance(sym.node, Var) and isinstance(
sym.node.type, AnyType):
return AnyType(
TypeOfAny.from_unimported_type,
missing_import_name=sym.node.type.missing_import_name)
# Option 2:
# Unbound type variable. Currently these may be still valid,
# for example when defining a generic type alias.
unbound_tvar = ((sym.kind == TVAR) and
(not self.tvar_scope
or self.tvar_scope.get_binding(sym) is None))
if self.allow_unbound_tvars and unbound_tvar and not self.third_pass:
return t
# Option 3:
# If it is not something clearly bad (like a known function, variable,
# type variable, or module), and it is still not too late, we try deferring
# this type using a forward reference wrapper. It will be revisited in
# the third pass.
allow_forward_ref = not (
self.third_pass or isinstance(sym.node,
(FuncDef, Decorator))
or isinstance(sym.node, Var) and sym.node.is_ready
or sym.kind in (MODULE_REF, TVAR))
if allow_forward_ref:
# We currently can't support subscripted forward refs in functions;
# see https://github.com/python/mypy/pull/3952#discussion_r139950690
# for discussion.
if t.args and not self.global_scope:
if not self.in_dynamic_func:
self.fail(
'Unsupported forward reference to "{}"'.format(
t.name), t)
return AnyType(TypeOfAny.from_error)
return ForwardRef(t)
# None of the above options worked, we give up.
self.fail('Invalid type "{}"'.format(name), t)
if self.third_pass and sym.kind == TVAR:
self.note_func(
"Forward references to type variables are prohibited",
t)
return AnyType(TypeOfAny.from_error)
# TODO: Would it be better to always return Any instead of UnboundType
# in case of an error? On one hand, UnboundType has a name so error messages
# are more detailed, on the other hand, some of them may be bogus.
return t
info = sym.node # type: TypeInfo
if len(t.args) > 0 and info.fullname() == 'builtins.tuple':
fallback = Instance(info, [AnyType(TypeOfAny.special_form)],
t.line)
return TupleType(self.anal_array(t.args), fallback, t.line)
else:
# Analyze arguments and construct Instance type. The
# number of type arguments and their values are
# checked only later, since we do not always know the
# valid count at this point. Thus we may construct an
# Instance with an invalid number of type arguments.
instance = Instance(info, self.anal_array(t.args), t.line,
t.column)
if not t.args and self.options.disallow_any_generics and not self.defining_alias:
# We report/patch invalid built-in instances already during second pass.
# This is done to avoid storing additional state on instances.
# All other (including user defined) generics will be patched/reported
# in the third pass.
if not self.is_typeshed_stub and info.fullname(
) in nongen_builtins:
alternative = nongen_builtins[info.fullname()]
self.fail(
messages.IMPLICIT_GENERIC_ANY_BUILTIN.format(
alternative), t)
any_type = AnyType(TypeOfAny.from_error, line=t.line)
else:
any_type = AnyType(TypeOfAny.from_omitted_generics,
line=t.line)
instance.args = [any_type] * len(info.type_vars)
tup = info.tuple_type
if tup is not None:
# The class has a Tuple[...] base class so it will be
# represented as a tuple type.
if t.args:
self.fail('Generic tuple types not supported', t)
return AnyType(TypeOfAny.from_error)
return tup.copy_modified(items=self.anal_array(tup.items),
fallback=instance)
td = info.typeddict_type
if td is not None:
# The class has a TypedDict[...] base class so it will be
# represented as a typeddict type.
if t.args:
self.fail('Generic TypedDict types not supported', t)
return AnyType(TypeOfAny.from_error)
# Create a named TypedDictType
return td.copy_modified(item_types=self.anal_array(
list(td.items.values())),
fallback=instance)
return instance
else:
if self.third_pass:
self.fail('Invalid type "{}"'.format(t.name), t)
return AnyType(TypeOfAny.from_error)
return AnyType(TypeOfAny.special_form)
def analyze_class_attribute_access(itype: Instance,
name: str,
mx: MemberContext) -> Optional[Type]:
"""original_type is the type of E in the expression E.var"""
node = itype.type.get(name)
if not node:
if itype.type.fallback_to_any:
return AnyType(TypeOfAny.special_form)
return None
is_decorated = isinstance(node.node, Decorator)
is_method = is_decorated or isinstance(node.node, FuncBase)
if mx.is_lvalue:
if is_method:
mx.msg.cant_assign_to_method(mx.context)
if isinstance(node.node, TypeInfo):
mx.msg.fail(messages.CANNOT_ASSIGN_TO_TYPE, mx.context)
# If a final attribute was declared on `self` in `__init__`, then it
# can't be accessed on the class object.
if node.implicit and isinstance(node.node, Var) and node.node.is_final:
mx.msg.fail(messages.CANNOT_ACCESS_FINAL_INSTANCE_ATTR
.format(node.node.name()), mx.context)
# An assignment to final attribute on class object is also always an error,
# independently of types.
if mx.is_lvalue and not mx.chk.get_final_context():
check_final_member(name, itype.type, mx.msg, mx.context)
if itype.type.is_enum and not (mx.is_lvalue or is_decorated or is_method):
return itype
t = node.type
if t:
if isinstance(t, PartialType):
symnode = node.node
assert isinstance(symnode, Var)
return mx.chk.handle_partial_var_type(t, mx.is_lvalue, symnode, mx.context)
if not is_method and (isinstance(t, TypeVarType) or get_type_vars(t)):
mx.msg.fail(messages.GENERIC_INSTANCE_VAR_CLASS_ACCESS, mx.context)
is_classmethod = ((is_decorated and cast(Decorator, node.node).func.is_class)
or (isinstance(node.node, FuncBase) and node.node.is_class))
result = add_class_tvars(t, itype, is_classmethod, mx.builtin_type, mx.original_type)
if not mx.is_lvalue:
result = analyze_descriptor_access(mx.original_type, result, mx.builtin_type,
mx.msg, mx.context, chk=mx.chk)
return result
elif isinstance(node.node, Var):
mx.not_ready_callback(name, mx.context)
return AnyType(TypeOfAny.special_form)
if isinstance(node.node, TypeVarExpr):
mx.msg.fail(messages.CANNOT_USE_TYPEVAR_AS_EXPRESSION.format(
itype.type.name(), name), mx.context)
return AnyType(TypeOfAny.from_error)
if isinstance(node.node, TypeInfo):
return type_object_type(node.node, mx.builtin_type)
if isinstance(node.node, MypyFile):
# Reference to a module object.
return mx.builtin_type('types.ModuleType')
if isinstance(node.node, TypeAlias) and isinstance(node.node.target, Instance):
return instance_alias_type(node.node, mx.builtin_type)
if is_decorated:
assert isinstance(node.node, Decorator)
if node.node.type:
return node.node.type
else:
mx.not_ready_callback(name, mx.context)
return AnyType(TypeOfAny.from_error)
else:
return function_type(cast(FuncBase, node.node), mx.builtin_type('builtins.function'))
def visit_unbound_type(self, t: UnboundType) -> Type:
if t.optional:
t.optional = False
# We don't need to worry about double-wrapping Optionals or
# wrapping Anys: Union simplification will take care of that.
return make_optional_type(self.visit_unbound_type(t))
sym = self.lookup(t.name, t, suppress_errors=self.third_pass) # type: ignore
if sym is not None:
if sym.node is None:
# UNBOUND_IMPORTED can happen if an unknown name was imported.
if sym.kind != UNBOUND_IMPORTED:
self.fail('Internal error (node is None, kind={})'.format(sym.kind), t)
return AnyType(TypeOfAny.special_form)
fullname = sym.node.fullname()
hook = self.plugin.get_type_analyze_hook(fullname)
if hook:
return hook(AnalyzeTypeContext(t, t, self))
if (fullname in nongen_builtins and t.args and
not sym.normalized and not self.allow_unnormalized):
self.fail(no_subscript_builtin_alias(fullname), t)
if self.tvar_scope:
tvar_def = self.tvar_scope.get_binding(sym)
else:
tvar_def = None
if self.warn_bound_tvar and sym.kind == TVAR and tvar_def is not None:
self.fail('Can\'t use bound type variable "{}"'
' to define generic alias'.format(t.name), t)
return AnyType(TypeOfAny.from_error)
elif sym.kind == TVAR and tvar_def is not None:
if len(t.args) > 0:
self.fail('Type variable "{}" used with arguments'.format(
t.name), t)
return TypeVarType(tvar_def, t.line)
elif fullname == 'builtins.None':
return NoneTyp()
elif fullname == 'typing.Any' or fullname == 'builtins.Any':
return AnyType(TypeOfAny.explicit)
elif fullname == 'typing.Tuple':
if len(t.args) == 0 and not t.empty_tuple_index:
# Bare 'Tuple' is same as 'tuple'
if self.options.disallow_any_generics and not self.is_typeshed_stub:
self.fail(messages.BARE_GENERIC, t)
typ = self.named_type('builtins.tuple', line=t.line, column=t.column)
typ.from_generic_builtin = True
return typ
if len(t.args) == 2 and isinstance(t.args[1], EllipsisType):
# Tuple[T, ...] (uniform, variable-length tuple)
instance = self.named_type('builtins.tuple', [self.anal_type(t.args[0])])
instance.line = t.line
return instance
return self.tuple_type(self.anal_array(t.args))
elif fullname == 'typing.Union':
items = self.anal_array(t.args)
return UnionType.make_union(items)
elif fullname == 'typing.Optional':
if len(t.args) != 1:
self.fail('Optional[...] must have exactly one type argument', t)
return AnyType(TypeOfAny.from_error)
item = self.anal_type(t.args[0])
return make_optional_type(item)
elif fullname == 'typing.Callable':
return self.analyze_callable_type(t)
elif fullname == 'typing.Type':
if len(t.args) == 0:
any_type = AnyType(TypeOfAny.from_omitted_generics,
line=t.line, column=t.column)
return TypeType(any_type, line=t.line, column=t.column)
if len(t.args) != 1:
self.fail('Type[...] must have exactly one type argument', t)
item = self.anal_type(t.args[0])
return TypeType.make_normalized(item, line=t.line)
elif fullname == 'typing.ClassVar':
if self.nesting_level > 0:
self.fail('Invalid type: ClassVar nested inside other type', t)
if len(t.args) == 0:
return AnyType(TypeOfAny.from_omitted_generics, line=t.line, column=t.column)
if len(t.args) != 1:
self.fail('ClassVar[...] must have at most one type argument', t)
return AnyType(TypeOfAny.from_error)
item = self.anal_type(t.args[0])
if isinstance(item, TypeVarType) or get_type_vars(item):
self.fail('Invalid type: ClassVar cannot be generic', t)
return AnyType(TypeOfAny.from_error)
return item
elif fullname in ('mypy_extensions.NoReturn', 'typing.NoReturn'):
return UninhabitedType(is_noreturn=True)
elif sym.kind == TYPE_ALIAS:
override = sym.type_override
all_vars = sym.alias_tvars
assert override is not None
an_args = self.anal_array(t.args)
if all_vars is not None:
exp_len = len(all_vars)
else:
exp_len = 0
act_len = len(an_args)
if exp_len > 0 and act_len == 0:
# Interpret bare Alias same as normal generic, i.e., Alias[Any, Any, ...]
assert all_vars is not None
return set_any_tvars(override, all_vars, t.line, t.column)
if exp_len == 0 and act_len == 0:
return override
if act_len != exp_len:
self.fail('Bad number of arguments for type alias, expected: %s, given: %s'
% (exp_len, act_len), t)
return set_any_tvars(override, all_vars or [],
t.line, t.column, implicit=False)
assert all_vars is not None
return replace_alias_tvars(override, all_vars, an_args, t.line, t.column)
elif not isinstance(sym.node, TypeInfo):
name = sym.fullname
if name is None:
name = sym.node.name()
if isinstance(sym.node, Var) and isinstance(sym.node.type, AnyType):
# Something with an Any type -- make it an alias for Any in a type
# context. This is slightly problematic as it allows using the type 'Any'
# as a base class -- however, this will fail soon at runtime so the problem
# is pretty minor.
return AnyType(TypeOfAny.from_unimported_type)
# Allow unbound type variables when defining an alias
if not (self.aliasing and sym.kind == TVAR and
(not self.tvar_scope or self.tvar_scope.get_binding(sym) is None)):
if (not self.third_pass and not self.in_dynamic_func and
not (isinstance(sym.node, (FuncDef, Decorator)) or
isinstance(sym.node, Var) and sym.node.is_ready) and
not (sym.kind == TVAR and tvar_def is None)):
if t.args and not self.global_scope:
self.fail('Unsupported forward reference to "{}"'.format(t.name), t)
return AnyType(TypeOfAny.from_error)
return ForwardRef(t)
self.fail('Invalid type "{}"'.format(name), t)
if self.third_pass and sym.kind == TVAR:
self.note_func("Forward references to type variables are prohibited", t)
return t
info = sym.node # type: TypeInfo
if len(t.args) > 0 and info.fullname() == 'builtins.tuple':
fallback = Instance(info, [AnyType(TypeOfAny.special_form)], t.line)
return TupleType(self.anal_array(t.args), fallback, t.line)
else:
# Analyze arguments and construct Instance type. The
# number of type arguments and their values are
# checked only later, since we do not always know the
# valid count at this point. Thus we may construct an
# Instance with an invalid number of type arguments.
instance = Instance(info, self.anal_array(t.args), t.line, t.column)
instance.from_generic_builtin = sym.normalized
tup = info.tuple_type
if tup is not None:
# The class has a Tuple[...] base class so it will be
# represented as a tuple type.
if t.args:
self.fail('Generic tuple types not supported', t)
return AnyType(TypeOfAny.from_error)
return tup.copy_modified(items=self.anal_array(tup.items),
fallback=instance)
td = info.typeddict_type
if td is not None:
# The class has a TypedDict[...] base class so it will be
# represented as a typeddict type.
if t.args:
self.fail('Generic TypedDict types not supported', t)
return AnyType(TypeOfAny.from_error)
# Create a named TypedDictType
return td.copy_modified(item_types=self.anal_array(list(td.items.values())),
fallback=instance)
return instance
else:
if self.third_pass:
self.fail('Invalid type "{}"'.format(t.name), t)
return AnyType(TypeOfAny.from_error)
return AnyType(TypeOfAny.special_form)
