Beispiel #1
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 def add_field(var: Var, is_initialized_in_class: bool = False,
               is_property: bool = False) -> None:
     var.info = info
     var.is_initialized_in_class = is_initialized_in_class
     var.is_property = is_property
     var._fullname = '%s.%s' % (info.fullname(), var.name())
     info.names[var.name()] = SymbolTableNode(MDEF, var)
Beispiel #2
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 def make_accessors(self, n: Var) -> List[Node]:
     if n.type:
         t = n.type
     else:
         t = AnyType()
     return [self.make_getter_wrapper(n.name(), t),
             self.make_setter_wrapper(n.name(), t),
             self.make_dynamic_getter_wrapper(n.name(), t),
             self.make_dynamic_setter_wrapper(n.name(), t)]
Beispiel #3
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def _make_frozen(ctx: 'mypy.plugin.ClassDefContext', attributes: List[Attribute]) -> None:
    """Turn all the attributes into properties to simulate frozen classes."""
    for attribute in attributes:
        if attribute.name in ctx.cls.info.names:
            # This variable belongs to this class so we can modify it.
            node = ctx.cls.info.names[attribute.name].node
            assert isinstance(node, Var)
            node.is_property = True
        else:
            # This variable belongs to a super class so create new Var so we
            # can modify it.
            var = Var(attribute.name, ctx.cls.info[attribute.name].type)
            var.info = ctx.cls.info
            var._fullname = '%s.%s' % (ctx.cls.info.fullname(), var.name())
            ctx.cls.info.names[var.name()] = SymbolTableNode(MDEF, var)
            var.is_property = True
Beispiel #4
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def analyze_var(
    name: str,
    var: Var,
    itype: Instance,
    info: TypeInfo,
    node: Context,
    is_lvalue: bool,
    msg: MessageBuilder,
    not_ready_callback: Callable[[str, Context], None],
) -> Type:
    """Analyze access to an attribute via a Var node.

    This is conceptually part of analyze_member_access and the arguments are similar.
    """
    # Found a member variable.
    itype = map_instance_to_supertype(itype, var.info)
    typ = var.type
    if typ:
        if isinstance(typ, PartialType):
            return handle_partial_attribute_type(typ, is_lvalue, msg, var)
        t = expand_type_by_instance(typ, itype)
        if is_lvalue and var.is_property and not var.is_settable_property:
            # TODO allow setting attributes in subclass (although it is probably an error)
            msg.read_only_property(name, info, node)
        if var.is_initialized_in_class and isinstance(t, FunctionLike):
            if is_lvalue:
                if var.is_property:
                    if not var.is_settable_property:
                        msg.read_only_property(name, info, node)
                else:
                    msg.cant_assign_to_method(node)

            if not var.is_staticmethod:
                # Class-level function objects and classmethods become bound
                # methods: the former to the instance, the latter to the
                # class.
                functype = t
                check_method_type(functype, itype, var.is_classmethod, node, msg)
                signature = method_type(functype)
                if var.is_property:
                    # A property cannot have an overloaded type => the cast
                    # is fine.
                    return cast(CallableType, signature).ret_type
                else:
                    return signature
        return t
    else:
        if not var.is_ready:
            not_ready_callback(var.name(), node)
        # Implicit 'Any' type.
        return AnyType()
Beispiel #5
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 def analyse_lvalue(self, lval, nested=False, add_defs=False):
     if isinstance(lval, NameExpr):
         n = lval
         nested_global = not self.locals and self.block_depth > 0 and not self.type
         if (add_defs or nested_global) and n.name not in self.globals:
             # Define new global name.
             v = Var(n.name)
             v._full_name = self.qualified_name(n.name)
             v.is_ready = False  # Type not inferred yet
             n.node = v
             n.is_def = True
             n.kind = GDEF
             n.full_name = v._full_name
             self.globals[n.name] = SymbolTableNode(GDEF, v, self.cur_mod_id)
         elif isinstance(n.node, Var) and n.is_def:
             v = n.node
             self.module_names[v.name()] = SymbolTableNode(GDEF, v, self.cur_mod_id)
         elif self.locals and n.name not in self.locals[-1] and n.name not in self.global_decls[-1]:
             # Define new local name.
             v = Var(n.name)
             n.node = v
             n.is_def = True
             n.kind = LDEF
             self.add_local(v, n)
         elif not self.locals and (self.type and n.name not in self.type.vars):
             # Define a new attribute.
             v = Var(n.name)
             v.info = self.type
             v.is_initialized_in_class = True
             n.node = v
             n.is_def = True
             self.type.vars[n.name] = v
         else:
             # Bind to an existing name.
             lval.accept(self)
     elif isinstance(lval, MemberExpr):
         if not add_defs:
             self.analyse_member_lvalue(lval)
     elif isinstance(lval, IndexExpr):
         if not add_defs:
             lval.accept(self)
     elif isinstance(lval, ParenExpr):
         self.analyse_lvalue((lval).expr, nested, add_defs)
     elif (isinstance(lval, TupleExpr) or isinstance(lval, ListExpr)) and not nested:
         items = (lval).items
         for i in items:
             self.analyse_lvalue(i, True, add_defs)
     else:
         self.fail("Invalid assignment target", lval)
Beispiel #6
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 def visit_var(self, node: Var) -> Var:
     # Note that a Var must be transformed to a Var.
     if node in self.var_map:
         return self.var_map[node]
     new = Var(node.name(), self.optional_type(node.type))
     new.line = node.line
     new._fullname = node._fullname
     new.info = node.info
     new.is_self = node.is_self
     new.is_ready = node.is_ready
     new.is_initialized_in_class = node.is_initialized_in_class
     new.is_staticmethod = node.is_staticmethod
     new.is_property = node.is_property
     new.set_line(node.line)
     self.var_map[node] = new
     return new
Beispiel #7
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def analyze_var(
    name: str, var: Var, itype: Instance, info: TypeInfo, node: Context, is_lvalue: bool, msg: MessageBuilder
) -> Type:
    """Analyze access to an attribute via a Var node.

    This is conceptually part of analyze_member_access and the arguments are similar.
    """
    # Found a member variable.
    itype = map_instance_to_supertype(itype, var.info)
    if var.type:
        t = expand_type_by_instance(var.type, itype)
        if var.is_initialized_in_class and isinstance(t, FunctionLike):
            if is_lvalue:
                if var.is_property:
                    if not var.is_settable_property:
                        msg.read_only_property(name, info, node)
                else:
                    msg.cant_assign_to_method(node)

            if not var.is_staticmethod:
                # Class-level function objects and classmethods become bound
                # methods: the former to the instance, the latter to the
                # class.
                functype = cast(FunctionLike, t)
                check_method_type(functype, itype, node, msg)
                signature = method_type(functype)
                if var.is_property:
                    # A property cannot have an overloaded type => the cast
                    # is fine.
                    return cast(CallableType, signature).ret_type
                else:
                    return signature
        return t
    else:
        if not var.is_ready:
            msg.cannot_determine_type(var.name(), node)
        # Implicit 'Any' type.
        return AnyType()
Beispiel #8
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def analyze_var(name: str,
                var: Var,
                itype: Instance,
                info: TypeInfo,
                mx: MemberContext, *,
                implicit: bool = False) -> Type:
    """Analyze access to an attribute via a Var node.

    This is conceptually part of analyze_member_access and the arguments are similar.

    itype is the class object in which var is defined
    original_type is the type of E in the expression E.var
    if implicit is True, the original Var was created as an assignment to self
    """
    # Found a member variable.
    itype = map_instance_to_supertype(itype, var.info)
    typ = var.type
    if typ:
        if isinstance(typ, PartialType):
            return mx.chk.handle_partial_var_type(typ, mx.is_lvalue, var, mx.context)
        t = expand_type_by_instance(typ, itype)
        if mx.is_lvalue and var.is_property and not var.is_settable_property:
            # TODO allow setting attributes in subclass (although it is probably an error)
            mx.msg.read_only_property(name, itype.type, mx.context)
        if mx.is_lvalue and var.is_classvar:
            mx.msg.cant_assign_to_classvar(name, mx.context)
        result = t
        if var.is_initialized_in_class and isinstance(t, FunctionLike) and not t.is_type_obj():
            if mx.is_lvalue:
                if var.is_property:
                    if not var.is_settable_property:
                        mx.msg.read_only_property(name, itype.type, mx.context)
                else:
                    mx.msg.cant_assign_to_method(mx.context)

            if not var.is_staticmethod:
                # Class-level function objects and classmethods become bound methods:
                # the former to the instance, the latter to the class.
                functype = t
                # Use meet to narrow original_type to the dispatched type.
                # For example, assume
                # * A.f: Callable[[A1], None] where A1 <: A (maybe A1 == A)
                # * B.f: Callable[[B1], None] where B1 <: B (maybe B1 == B)
                # * x: Union[A1, B1]
                # In `x.f`, when checking `x` against A1 we assume x is compatible with A
                # and similarly for B1 when checking agains B
                dispatched_type = meet.meet_types(mx.original_type, itype)
                check_self_arg(functype, dispatched_type, var.is_classmethod, mx.context, name,
                               mx.msg)
                signature = bind_self(functype, mx.original_type, var.is_classmethod)
                if var.is_property:
                    # A property cannot have an overloaded type => the cast is fine.
                    assert isinstance(signature, CallableType)
                    result = signature.ret_type
                else:
                    result = signature
    else:
        if not var.is_ready:
            mx.not_ready_callback(var.name(), mx.context)
        # Implicit 'Any' type.
        result = AnyType(TypeOfAny.special_form)
    fullname = '{}.{}'.format(var.info.fullname(), name)
    hook = mx.chk.plugin.get_attribute_hook(fullname)
    if result and not mx.is_lvalue and not implicit:
        result = analyze_descriptor_access(mx.original_type, result, mx.builtin_type,
                                           mx.msg, mx.context, chk=mx.chk)
    if hook:
        result = hook(AttributeContext(mx.original_type, result, mx.context, mx.chk))
    return result
Beispiel #9
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 def make_init_arg(var: Var) -> Argument:
     default = default_items.get(var.name(), None)
     kind = ARG_POS if default is None else ARG_OPT
     return Argument(var, var.type, default, kind)
Beispiel #10
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def analyze_var(name: str,
                var: Var,
                itype: Instance,
                info: TypeInfo,
                mx: MemberContext,
                *,
                implicit: bool = False) -> Type:
    """Analyze access to an attribute via a Var node.

    This is conceptually part of analyze_member_access and the arguments are similar.

    itype is the class object in which var is defined
    original_type is the type of E in the expression E.var
    if implicit is True, the original Var was created as an assignment to self
    """
    # Found a member variable.
    itype = map_instance_to_supertype(itype, var.info)
    typ = var.type
    if typ:
        if isinstance(typ, PartialType):
            return mx.chk.handle_partial_var_type(typ, mx.is_lvalue, var,
                                                  mx.context)
        t = expand_type_by_instance(typ, itype)
        if mx.is_lvalue and var.is_property and not var.is_settable_property:
            # TODO allow setting attributes in subclass (although it is probably an error)
            mx.msg.read_only_property(name, itype.type, mx.context)
        if mx.is_lvalue and var.is_classvar:
            mx.msg.cant_assign_to_classvar(name, mx.context)
        result = t
        if var.is_initialized_in_class and isinstance(
                t, FunctionLike) and not t.is_type_obj():
            if mx.is_lvalue:
                if var.is_property:
                    if not var.is_settable_property:
                        mx.msg.read_only_property(name, itype.type, mx.context)
                else:
                    mx.msg.cant_assign_to_method(mx.context)

            if not var.is_staticmethod:
                # Class-level function objects and classmethods become bound methods:
                # the former to the instance, the latter to the class.
                functype = t
                # Use meet to narrow original_type to the dispatched type.
                # For example, assume
                # * A.f: Callable[[A1], None] where A1 <: A (maybe A1 == A)
                # * B.f: Callable[[B1], None] where B1 <: B (maybe B1 == B)
                # * x: Union[A1, B1]
                # In `x.f`, when checking `x` against A1 we assume x is compatible with A
                # and similarly for B1 when checking agains B
                dispatched_type = meet.meet_types(mx.original_type, itype)
                check_self_arg(functype, dispatched_type, var.is_classmethod,
                               mx.context, name, mx.msg)
                signature = bind_self(functype, mx.self_type,
                                      var.is_classmethod)
                if var.is_property:
                    # A property cannot have an overloaded type => the cast is fine.
                    assert isinstance(signature, CallableType)
                    result = signature.ret_type
                else:
                    result = signature
    else:
        if not var.is_ready:
            mx.not_ready_callback(var.name(), mx.context)
        # Implicit 'Any' type.
        result = AnyType(TypeOfAny.special_form)
    fullname = '{}.{}'.format(var.info.fullname(), name)
    hook = mx.chk.plugin.get_attribute_hook(fullname)
    if result and not mx.is_lvalue and not implicit:
        result = analyze_descriptor_access(mx.original_type,
                                           result,
                                           mx.builtin_type,
                                           mx.msg,
                                           mx.context,
                                           chk=mx.chk)
    if hook:
        result = hook(
            AttributeContext(mx.original_type, result, mx.context, mx.chk))
    return result
Beispiel #11
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 def make_init_arg(var: Var) -> Argument:
     default = default_items.get(var.name(), None)
     kind = ARG_POS if default is None else ARG_OPT
     return Argument(var, var.type, default, kind)