Python MessageBuilder.deleted_as_rvalue方法代码示例

# 需要导入模块: from mypy.messages import MessageBuilder [as 别名]
# 或者: from mypy.messages.MessageBuilder import deleted_as_rvalue [as 别名]
def analyze_member_access(name: str, typ: Type, node: Context, is_lvalue: bool,
                          is_super: bool,
                          builtin_type: Callable[[str], Instance],
                          not_ready_callback: Callable[[str, Context], None],
                          msg: MessageBuilder, override_info: TypeInfo = None,
                          report_type: Type = None) -> Type:
    """Analyse attribute access.

    This is a general operation that supports various different variations:

      1. lvalue or non-lvalue access (i.e. setter or getter access)
      2. supertype access (when using super(); is_super == True and
         override_info should refer to the supertype)
    """
    report_type = report_type or typ
    if isinstance(typ, Instance):
        if name == '__init__' and not is_super:
            # Accessing __init__ in statically typed code would compromise
            # type safety unless used via super().
            msg.fail(messages.CANNOT_ACCESS_INIT, node)
            return AnyType()

        # The base object has an instance type.

        info = typ.type
        if override_info:
            info = override_info

        # Look up the member. First look up the method dictionary.
        method = info.get_method(name)
        if method:
            if method.is_property:
                assert isinstance(method, OverloadedFuncDef)
                method = cast(OverloadedFuncDef, method)
                return analyze_var(name, method.items[0].var, typ, info, node, is_lvalue, msg,
                                   not_ready_callback)
            if is_lvalue:
                msg.cant_assign_to_method(node)
            typ = map_instance_to_supertype(typ, method.info)
            if name == '__new__':
                # __new__ is special and behaves like a static method -- don't strip
                # the first argument.
                signature = function_type(method, builtin_type('builtins.function'))
            else:
                signature = method_type_with_fallback(method, builtin_type('builtins.function'))
            return expand_type_by_instance(signature, typ)
        else:
            # Not a method.
            return analyze_member_var_access(name, typ, info, node,
                                             is_lvalue, is_super, builtin_type,
                                             not_ready_callback, msg,
                                             report_type=report_type)
    elif isinstance(typ, AnyType):
        # The base object has dynamic type.
        return AnyType()
    elif isinstance(typ, UnionType):
        # The base object has dynamic type.
        msg.disable_type_names += 1
        results = [analyze_member_access(name, subtype, node, is_lvalue,
                                         is_super, builtin_type, not_ready_callback, msg)
                   for subtype in typ.items]
        msg.disable_type_names -= 1
        return UnionType.make_simplified_union(results)
    elif isinstance(typ, TupleType):
        # Actually look up from the fallback instance type.
        return analyze_member_access(name, typ.fallback, node, is_lvalue,
                                     is_super, builtin_type, not_ready_callback, msg)
    elif isinstance(typ, FunctionLike) and typ.is_type_obj():
        # Class attribute.
        # TODO super?
        ret_type = typ.items()[0].ret_type
        if isinstance(ret_type, TupleType):
            ret_type = ret_type.fallback
        if isinstance(ret_type, Instance):
            result = analyze_class_attribute_access(ret_type, name, node, is_lvalue,
                                                    builtin_type, not_ready_callback, msg)
            if result:
                return result
            # Look up from the 'type' type.
            return analyze_member_access(name, typ.fallback, node, is_lvalue, is_super,
                                         builtin_type, not_ready_callback, msg,
                                         report_type=report_type)
        else:
            assert False, 'Unexpected type {}'.format(repr(ret_type))
    elif isinstance(typ, FunctionLike):
        # Look up from the 'function' type.
        return analyze_member_access(name, typ.fallback, node, is_lvalue, is_super,
                                     builtin_type, not_ready_callback, msg,
                                     report_type=report_type)
    elif isinstance(typ, TypeVarType):
        return analyze_member_access(name, typ.upper_bound, node, is_lvalue, is_super,
                                     builtin_type, not_ready_callback, msg,
                                     report_type=report_type)
    elif isinstance(typ, DeletedType):
        msg.deleted_as_rvalue(typ, node)
        return AnyType()
    return msg.has_no_attr(report_type, name, node)

# 需要导入模块: from mypy.messages import MessageBuilder [as 别名]
# 或者: from mypy.messages.MessageBuilder import deleted_as_rvalue [as 别名]

#.........这里部分代码省略.........
            ret_type = ret_type.fallback
        if isinstance(ret_type, Instance):
            if not is_operator:
                # When Python sees an operator (eg `3 == 4`), it automatically translates that
                # into something like `int.__eq__(3, 4)` instead of `(3).__eq__(4)` as an
                # optimation.
                #
                # While it normally it doesn't matter which of the two versions are used, it
                # does cause inconsistencies when working with classes. For example, translating
                # `int == int` to `int.__eq__(int)` would not work since `int.__eq__` is meant to
                # compare two int _instances_. What we really want is `type(int).__eq__`, which
                # is meant to compare two types or classes.
                #
                # This check makes sure that when we encounter an operator, we skip looking up
                # the corresponding method in the current instance to avoid this edge case.
                # See https://github.com/python/mypy/pull/1787 for more info.
                result = analyze_class_attribute_access(
                    ret_type, name, node, is_lvalue, builtin_type, not_ready_callback, msg
                )
                if result:
                    return result
            # Look up from the 'type' type.
            return analyze_member_access(
                name,
                typ.fallback,
                node,
                is_lvalue,
                is_super,
                is_operator,
                builtin_type,
                not_ready_callback,
                msg,
                report_type=report_type,
                chk=chk,
            )
        else:
            assert False, "Unexpected type {}".format(repr(ret_type))
    elif isinstance(typ, FunctionLike):
        # Look up from the 'function' type.
        return analyze_member_access(
            name,
            typ.fallback,
            node,
            is_lvalue,
            is_super,
            is_operator,
            builtin_type,
            not_ready_callback,
            msg,
            report_type=report_type,
            chk=chk,
        )
    elif isinstance(typ, TypeVarType):
        return analyze_member_access(
            name,
            typ.upper_bound,
            node,
            is_lvalue,
            is_super,
            is_operator,
            builtin_type,
            not_ready_callback,
            msg,
            report_type=report_type,
            chk=chk,
        )
    elif isinstance(typ, DeletedType):
        msg.deleted_as_rvalue(typ, node)
        return AnyType()
    elif isinstance(typ, TypeType):
        # Similar to FunctionLike + is_type_obj() above.
        item = None
        if isinstance(typ.item, Instance):
            item = typ.item
        elif isinstance(typ.item, TypeVarType):
            if isinstance(typ.item.upper_bound, Instance):
                item = typ.item.upper_bound
        if item and not is_operator:
            # See comment above for why operators are skipped
            result = analyze_class_attribute_access(item, name, node, is_lvalue, builtin_type, not_ready_callback, msg)
            if result:
                return result
        fallback = builtin_type("builtins.type")
        return analyze_member_access(
            name,
            fallback,
            node,
            is_lvalue,
            is_super,
            is_operator,
            builtin_type,
            not_ready_callback,
            msg,
            report_type=report_type,
            chk=chk,
        )

    if chk and chk.should_suppress_optional_error([typ]):
        return AnyType()
    return msg.has_no_attr(report_type, name, node)

# 需要导入模块: from mypy.messages import MessageBuilder [as 别名]
# 或者: from mypy.messages.MessageBuilder import deleted_as_rvalue [as 别名]

#.........这里部分代码省略.........
                   for subtype in typ.relevant_items()]
        msg.disable_type_names -= 1
        return UnionType.make_simplified_union(results)
    elif isinstance(typ, TupleType):
        # Actually look up from the fallback instance type.
        return analyze_member_access(name, typ.fallback, node, is_lvalue, is_super,
                                     is_operator, builtin_type, not_ready_callback, msg,
                                     original_type=original_type, chk=chk)
    elif isinstance(typ, TypedDictType):
        # Actually look up from the fallback instance type.
        return analyze_member_access(name, typ.fallback, node, is_lvalue, is_super,
                                     is_operator, builtin_type, not_ready_callback, msg,
                                     original_type=original_type, chk=chk)
    elif isinstance(typ, FunctionLike) and typ.is_type_obj():
        # Class attribute.
        # TODO super?
        ret_type = typ.items()[0].ret_type
        if isinstance(ret_type, TupleType):
            ret_type = ret_type.fallback
        if isinstance(ret_type, Instance):
            if not is_operator:
                # When Python sees an operator (eg `3 == 4`), it automatically translates that
                # into something like `int.__eq__(3, 4)` instead of `(3).__eq__(4)` as an
                # optimization.
                #
                # While it normally it doesn't matter which of the two versions are used, it
                # does cause inconsistencies when working with classes. For example, translating
                # `int == int` to `int.__eq__(int)` would not work since `int.__eq__` is meant to
                # compare two int _instances_. What we really want is `type(int).__eq__`, which
                # is meant to compare two types or classes.
                #
                # This check makes sure that when we encounter an operator, we skip looking up
                # the corresponding method in the current instance to avoid this edge case.
                # See https://github.com/python/mypy/pull/1787 for more info.
                result = analyze_class_attribute_access(ret_type, name, node, is_lvalue,
                                                        builtin_type, not_ready_callback, msg,
                                                        original_type=original_type)
                if result:
                    return result
            # Look up from the 'type' type.
            return analyze_member_access(name, typ.fallback, node, is_lvalue, is_super,
                                         is_operator, builtin_type, not_ready_callback, msg,
                                         original_type=original_type, chk=chk)
        else:
            assert False, 'Unexpected type {}'.format(repr(ret_type))
    elif isinstance(typ, FunctionLike):
        # Look up from the 'function' type.
        return analyze_member_access(name, typ.fallback, node, is_lvalue, is_super,
                                     is_operator, builtin_type, not_ready_callback, msg,
                                     original_type=original_type, chk=chk)
    elif isinstance(typ, TypeVarType):
        return analyze_member_access(name, typ.upper_bound, node, is_lvalue, is_super,
                                     is_operator, builtin_type, not_ready_callback, msg,
                                     original_type=original_type, chk=chk)
    elif isinstance(typ, DeletedType):
        msg.deleted_as_rvalue(typ, node)
        return AnyType(TypeOfAny.from_error)
    elif isinstance(typ, TypeType):
        # Similar to FunctionLike + is_type_obj() above.
        item = None
        fallback = builtin_type('builtins.type')
        ignore_messages = msg.copy()
        ignore_messages.disable_errors()
        if isinstance(typ.item, Instance):
            item = typ.item
        elif isinstance(typ.item, AnyType):
            return analyze_member_access(name, fallback, node, is_lvalue, is_super,
                                     is_operator, builtin_type, not_ready_callback,
                                     ignore_messages, original_type=original_type, chk=chk)
        elif isinstance(typ.item, TypeVarType):
            if isinstance(typ.item.upper_bound, Instance):
                item = typ.item.upper_bound
        elif isinstance(typ.item, TupleType):
            item = typ.item.fallback
        elif isinstance(typ.item, FunctionLike) and typ.item.is_type_obj():
            item = typ.item.fallback
        elif isinstance(typ.item, TypeType):
            # Access member on metaclass object via Type[Type[C]]
            if isinstance(typ.item.item, Instance):
                item = typ.item.item.type.metaclass_type
        if item and not is_operator:
            # See comment above for why operators are skipped
            result = analyze_class_attribute_access(item, name, node, is_lvalue,
                                                    builtin_type, not_ready_callback, msg,
                                                    original_type=original_type)
            if result:
                if not (isinstance(result, AnyType) and item.type.fallback_to_any):
                    return result
                else:
                    # We don't want errors on metaclass lookup for classes with Any fallback
                    msg = ignore_messages
        if item is not None:
            fallback = item.type.metaclass_type or fallback
        return analyze_member_access(name, fallback, node, is_lvalue, is_super,
                                     is_operator, builtin_type, not_ready_callback, msg,
                                     original_type=original_type, chk=chk)

    if chk.should_suppress_optional_error([typ]):
        return AnyType(TypeOfAny.from_error)
    return msg.has_no_attr(original_type, typ, name, node)