def subscript_has_child_names_resolved():
_assert_children_resolved(
lambda ref: nodes.subscript(ref, nodes.none()),
)
_assert_children_resolved(
lambda ref: nodes.subscript(nodes.none(), ref),
)
def can_infer_type_of_subscript_using_getitem():
cls = types.class_type("Blah", [
types.attr("__getitem__", types.func([types.int_type], types.str_type)),
])
type_bindings = {"x": cls}
node = nodes.subscript(nodes.ref("x"), nodes.int_literal(4))
assert_equal(types.str_type, infer(node, type_bindings=type_bindings))
def test_transform_setitem_subscript(self):
_assert_transform(
nodes.assign([nodes.subscript(nodes.ref("x"), nodes.ref("y"))], nodes.ref("z")),
"""
var __nope_u_tmp0 = z
x.__setitem__(y, __nope_u_tmp0)
"""
)
def for_statement_target_can_be_supertype_of_iterable_element_type():
ref_node = nodes.ref("xs")
node = nodes.for_(nodes.subscript(nodes.ref("ys"), nodes.int_literal(0)), ref_node, [])
update_context(node, type_bindings={
"xs": types.list_type(types.int_type),
"ys": types.list_type(types.object_type),
})
def assignment_to_list_does_not_allow_supertype():
target_sequence_node = nodes.ref("x")
value_node = nodes.ref("y")
node = nodes.assign([nodes.subscript(target_sequence_node, nodes.int_literal(0))], value_node)
type_bindings = {
"x": types.list_type(types.str_type),
"y": types.object_type,
}
try:
update_context(node, type_bindings=type_bindings)
assert False, "Expected error"
except errors.UnexpectedTargetTypeError as error:
assert_equal(target_sequence_node, ephemeral.root_node(error.node))
assert_equal(
ephemeral.FormalArg(ephemeral.attr(target_sequence_node, "__setitem__"), 1),
ephemeral.underlying_node(error.node)
)
assert_equal(types.object_type, error.value_type)
assert_equal(types.str_type, error.target_type)
def for_statement_target_cannot_be_strict_subtype_of_iterable_element_type():
target_sequence_node = nodes.ref("ys")
target_node = nodes.subscript(target_sequence_node, nodes.int_literal(0))
iterable_node = nodes.ref("xs")
node = nodes.for_(target_node, iterable_node, [])
try:
update_context(node, type_bindings={
"xs": types.list_type(types.object_type),
"ys": types.list_type(types.int_type),
})
assert False, "Expected error"
except errors.UnexpectedTargetTypeError as error:
assert_equal(target_sequence_node, ephemeral.root_node(error.node))
assert_equal(
ephemeral.FormalArg(ephemeral.attr(target_sequence_node, "__setitem__"), 1),
ephemeral.underlying_node(error.node)
)
assert_equal(types.object_type, error.value_type)
assert_equal(types.int_type, error.target_type)
def can_infer_type_of_subscript_of_list():
type_bindings = {"x": types.list_type(types.str_type)}
node = nodes.subscript(nodes.ref("x"), nodes.int_literal(4))
assert_equal(types.str_type, infer(node, type_bindings=type_bindings))
def test_missing_subscript_slice_values_are_treated_as_none():
expected = nodes.subscript(nodes.ref("x"), nodes.slice(nodes.none(), nodes.none(), nodes.none()))
_assert_expression_parse(expected, "x[:]")
def test_parse_subscript_with_slice():
expected = nodes.subscript(
nodes.ref("x"),
nodes.slice(nodes.ref("a"), nodes.ref("b"), nodes.ref("c")),
)
_assert_expression_parse(expected, "x[a:b:c]")
def test_parse_subscript_with_index():
expected = nodes.subscript(nodes.ref("x"), nodes.ref("y"))
_assert_expression_parse(expected, "x[y]")
def assignment_to_list_allows_subtype():
node = nodes.assign([nodes.subscript(nodes.ref("x"), nodes.int_literal(0))], nodes.str_literal("Hello"))
type_bindings = {"x": types.list_type(types.object_type)}
update_context(node, type_bindings=type_bindings)
def test_transform_getitem(self):
_assert_transform(
nodes.subscript(nodes.ref("x"), nodes.ref("y")),
cc.call(cc.attr(cc.ref("x"), "__getitem__"), [cc.ref("y")])
)