LibJS: Add Object.{isExtensible,preventExtensions}()

This commit is contained in:
Matthew Olsson 2020-06-01 21:13:16 -07:00 committed by Andreas Kling
parent daa3f59a55
commit d5ae73a63b
Notes: sideshowbarker 2024-07-19 05:54:04 +09:00
6 changed files with 118 additions and 0 deletions

View file

@ -89,6 +89,12 @@ bool Object::has_prototype(const Object* prototype) const
return false;
}
bool Object::prevent_extensions()
{
m_is_extensible = false;
return true;
}
Value Object::get_own_property(const Object& this_object, PropertyName property_name) const
{
Value value_here;
@ -308,6 +314,13 @@ bool Object::put_own_property(Object& this_object, const FlyString& property_nam
{
ASSERT(!(mode == PutOwnPropertyMode::Put && value.is_accessor()));
if (!is_extensible()) {
dbg() << "Disallow define_property of non-extensible object";
if (throw_exceptions && interpreter().in_strict_mode())
interpreter().throw_exception<TypeError>(String::format("Cannot define property %s on non-extensible object", property_name.characters()));
return false;
}
if (value.is_accessor()) {
auto& accessor = value.as_accessor();
if (accessor.getter())
@ -375,6 +388,13 @@ bool Object::put_own_property_by_index(Object& this_object, u32 property_index,
{
ASSERT(!(mode == PutOwnPropertyMode::Put && value.is_accessor()));
if (!is_extensible()) {
dbg() << "Disallow define_property of non-extensible object";
if (throw_exceptions && interpreter().in_strict_mode())
interpreter().throw_exception<TypeError>(String::format("Cannot define property %d on non-extensible object", property_index));
return false;
}
if (value.is_accessor()) {
auto& accessor = value.as_accessor();
if (accessor.getter())

View file

@ -98,6 +98,9 @@ public:
void set_prototype(Object*);
bool has_prototype(const Object* prototype) const;
bool is_extensible() const { return m_is_extensible; }
bool prevent_extensions();
virtual Value value_of() const { return Value(const_cast<Object*>(this)); }
virtual Value to_primitive(Value::PreferredType preferred_type = Value::PreferredType::Default) const;
virtual Value to_string() const;
@ -122,6 +125,7 @@ private:
void set_shape(Shape&);
void ensure_shape_is_unique();
bool m_is_extensible { true };
Shape* m_shape { nullptr };
Vector<Value> m_storage;
IndexedProperties m_indexed_properties;

View file

@ -48,6 +48,8 @@ ObjectConstructor::ObjectConstructor()
define_native_function("getOwnPropertyNames", get_own_property_names, 1, attr);
define_native_function("getPrototypeOf", get_prototype_of, 1, attr);
define_native_function("setPrototypeOf", set_prototype_of, 2, attr);
define_native_function("isExtensible", is_extensible, 1, attr);
define_native_function("preventExtensions", prevent_extensions, 1, attr);
define_native_function("keys", keys, 1, attr);
define_native_function("values", values, 1, attr);
define_native_function("entries", entries, 1, attr);
@ -104,6 +106,26 @@ Value ObjectConstructor::set_prototype_of(Interpreter& interpreter)
return {};
}
Value ObjectConstructor::is_extensible(Interpreter& interpreter)
{
auto argument = interpreter.argument(0);
if (!argument.is_object())
return Value(false);
return Value(argument.as_object().is_extensible());
}
Value ObjectConstructor::prevent_extensions(Interpreter& interpreter)
{
auto argument = interpreter.argument(0);
if (!argument.is_object())
return argument;
if (!argument.as_object().prevent_extensions()) {
interpreter.throw_exception<TypeError>("Proxy preventExtensions handler returned false");
return {};
}
return argument;
}
Value ObjectConstructor::get_own_property_descriptor(Interpreter& interpreter)
{
auto* object = interpreter.argument(0).to_object(interpreter);

View file

@ -48,6 +48,8 @@ private:
static Value get_own_property_names(Interpreter&);
static Value get_prototype_of(Interpreter&);
static Value set_prototype_of(Interpreter&);
static Value is_extensible(Interpreter&);
static Value prevent_extensions(Interpreter&);
static Value keys(Interpreter&);
static Value values(Interpreter&);
static Value entries(Interpreter&);

View file

@ -0,0 +1,22 @@
load("test-common.js");
try {
assert(Object.isExtensible() === false);
assert(Object.isExtensible(undefined) === false);
assert(Object.isExtensible(null) === false);
assert(Object.isExtensible(true) === false);
assert(Object.isExtensible(6) === false);
assert(Object.isExtensible("test") === false);
let s = Symbol();
assert(Object.isExtensible(s) === false);
let o = { foo: "foo" };
assert(Object.isExtensible(o) === true);
Object.preventExtensions(o);
assert(Object.isExtensible(o) === false);
console.log("PASS");
} catch (e) {
console.log("FAIL: " + e);
}

View file

@ -0,0 +1,48 @@
load("test-common.js");
try {
assert(Object.preventExtensions() === undefined);
assert(Object.preventExtensions(undefined) === undefined);
assert(Object.preventExtensions(null) === null);
assert(Object.preventExtensions(true) === true);
assert(Object.preventExtensions(6) === 6);
assert(Object.preventExtensions("test") === "test");
let s = Symbol();
assert(Object.preventExtensions(s) === s);
let o = { foo: "foo" };
assert(o.foo === "foo");
o.bar = "bar";
assert(o.bar === "bar");
assert(Object.preventExtensions(o) === o);
assert(o.foo === "foo");
assert(o.bar === "bar");
o.baz = "baz";
assert(o.baz === undefined);
Object.defineProperty(o, "baz", { value: "baz" });
assert(o.baz === undefined);
assertThrowsError(() => {
"use strict";
o.baz = "baz";
}, {
error: TypeError,
message: "Cannot define property baz on non-extensible object",
});
assertThrowsError(() => {
"use strict";
Object.defineProperty(o, "baz", { value: "baz" });
}, {
error: TypeError,
message: "Cannot define property baz on non-extensible object",
});
console.log("PASS");
} catch (e) {
console.log("FAIL: " + e);
}