Beispiel #1
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def cache_class_attrs(builder: IRBuilder, attrs_to_cache: List[Lvalue], cdef: ClassDef) -> None:
    """Add class attributes to be cached to the global cache"""
    typ = builder.load_native_type_object(cdef.fullname)
    for lval in attrs_to_cache:
        assert isinstance(lval, NameExpr)
        rval = builder.py_get_attr(typ, lval.name, cdef.line)
        builder.init_final_static(lval, rval, cdef.name)
Beispiel #2
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def transform_assignment_stmt(builder: IRBuilder, stmt: AssignmentStmt) -> None:
    assert len(stmt.lvalues) >= 1
    builder.disallow_class_assignments(stmt.lvalues, stmt.line)
    lvalue = stmt.lvalues[0]
    if stmt.type and isinstance(stmt.rvalue, TempNode):
        # This is actually a variable annotation without initializer. Don't generate
        # an assignment but we need to call get_assignment_target since it adds a
        # name binding as a side effect.
        builder.get_assignment_target(lvalue, stmt.line)
        return

    line = stmt.rvalue.line
    rvalue_reg = builder.accept(stmt.rvalue)
    if builder.non_function_scope() and stmt.is_final_def:
        builder.init_final_static(lvalue, rvalue_reg)
    for lvalue in stmt.lvalues:
        target = builder.get_assignment_target(lvalue)
        builder.assign(target, rvalue_reg, line)
Beispiel #3
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def transform_class_def(builder: IRBuilder, cdef: ClassDef) -> None:
    ir = builder.mapper.type_to_ir[cdef.info]

    # We do this check here because the base field of parent
    # classes aren't necessarily populated yet at
    # prepare_class_def time.
    if any(ir.base_mro[i].base != ir. base_mro[i + 1] for i in range(len(ir.base_mro) - 1)):
        builder.error("Non-trait MRO must be linear", cdef.line)

    if ir.allow_interpreted_subclasses:
        for parent in ir.mro:
            if not parent.allow_interpreted_subclasses:
                builder.error(
                    'Base class "{}" does not allow interpreted subclasses'.format(
                        parent.fullname), cdef.line)

    # Currently, we only create non-extension classes for classes that are
    # decorated or inherit from Enum. Classes decorated with @trait do not
    # apply here, and are handled in a different way.
    if ir.is_ext_class:
        # If the class is not decorated, generate an extension class for it.
        type_obj = allocate_class(builder, cdef)  # type: Optional[Value]
        non_ext = None  # type: Optional[NonExtClassInfo]
        dataclass_non_ext = dataclass_non_ext_info(builder, cdef)
    else:
        non_ext_bases = populate_non_ext_bases(builder, cdef)
        non_ext_metaclass = find_non_ext_metaclass(builder, cdef, non_ext_bases)
        non_ext_dict = setup_non_ext_dict(builder, cdef, non_ext_metaclass, non_ext_bases)
        # We populate __annotations__ for non-extension classes
        # because dataclasses uses it to determine which attributes to compute on.
        # TODO: Maybe generate more precise types for annotations
        non_ext_anns = builder.primitive_op(new_dict_op, [], cdef.line)
        non_ext = NonExtClassInfo(non_ext_dict, non_ext_bases, non_ext_anns, non_ext_metaclass)
        dataclass_non_ext = None
        type_obj = None

    attrs_to_cache = []  # type: List[Lvalue]

    for stmt in cdef.defs.body:
        if isinstance(stmt, OverloadedFuncDef) and stmt.is_property:
            if not ir.is_ext_class:
                # properties with both getters and setters in non_extension
                # classes not supported
                builder.error("Property setters not supported in non-extension classes",
                           stmt.line)
            for item in stmt.items:
                with builder.catch_errors(stmt.line):
                    transform_method(builder, cdef, non_ext, get_func_def(item))
        elif isinstance(stmt, (FuncDef, Decorator, OverloadedFuncDef)):
            # Ignore plugin generated methods (since they have no
            # bodies to compile and will need to have the bodies
            # provided by some other mechanism.)
            if cdef.info.names[stmt.name].plugin_generated:
                continue
            with builder.catch_errors(stmt.line):
                transform_method(builder, cdef, non_ext, get_func_def(stmt))
        elif isinstance(stmt, PassStmt):
            continue
        elif isinstance(stmt, AssignmentStmt):
            if len(stmt.lvalues) != 1:
                builder.error("Multiple assignment in class bodies not supported", stmt.line)
                continue
            lvalue = stmt.lvalues[0]
            if not isinstance(lvalue, NameExpr):
                builder.error("Only assignment to variables is supported in class bodies",
                           stmt.line)
                continue
            # We want to collect class variables in a dictionary for both real
            # non-extension classes and fake dataclass ones.
            var_non_ext = non_ext or dataclass_non_ext
            if var_non_ext:
                add_non_ext_class_attr(builder, var_non_ext, lvalue, stmt, cdef, attrs_to_cache)
                if non_ext:
                    continue
            # Variable declaration with no body
            if isinstance(stmt.rvalue, TempNode):
                continue
            # Only treat marked class variables as class variables.
            if not (is_class_var(lvalue) or stmt.is_final_def):
                continue
            typ = builder.load_native_type_object(cdef.fullname)
            value = builder.accept(stmt.rvalue)
            builder.primitive_op(
                py_setattr_op, [typ, builder.load_static_unicode(lvalue.name), value], stmt.line)
            if builder.non_function_scope() and stmt.is_final_def:
                builder.init_final_static(lvalue, value, cdef.name)
        elif isinstance(stmt, ExpressionStmt) and isinstance(stmt.expr, StrExpr):
            # Docstring. Ignore
            pass
        else:
            builder.error("Unsupported statement in class body", stmt.line)

    if not non_ext:  # That is, an extension class
        generate_attr_defaults(builder, cdef)
        create_ne_from_eq(builder, cdef)
        if dataclass_non_ext:
            assert type_obj
            dataclass_finalize(builder, cdef, dataclass_non_ext, type_obj)
    else:
        # Dynamically create the class via the type constructor
        non_ext_class = load_non_ext_class(builder, ir, non_ext, cdef.line)
        non_ext_class = load_decorated_class(builder, cdef, non_ext_class)

        # Save the decorated class
        builder.add(InitStatic(non_ext_class, cdef.name, builder.module_name, NAMESPACE_TYPE))

        # Add the non-extension class to the dict
        builder.primitive_op(dict_set_item_op,
                          [
                              builder.load_globals_dict(),
                              builder.load_static_unicode(cdef.name),
                              non_ext_class
                          ], cdef.line)

        # Cache any cachable class attributes
        cache_class_attrs(builder, attrs_to_cache, cdef)