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)
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)