Nicolò Ribaudo c5279eeca4
[static private] Use explicit descriptors instead of an object (#8620)
This is similar to ec69b4bb1256c061ac76f53dfed09c4283ec6a31, which
was about private instance fields.

Private properties can be non-writable (thanks to decorators), or have
get/set accessors. If we stored this information on the `privateClass`
object, we would need to always use `Object.getOwnPropertyDescriptor`
before reading or writing a property because accessors need to be called
with the correct `this` context (it should be the actual class, not the
object hat stores the private properties). This commit simplifies that
operation a bit by removing the container object.

It also have another advantage, which instance fields already have
thanks to the use of separate weakmaps: unused private static fields
can be tree-shaken away or garbage-collected, while properties of an
object can't. Also, they can be easilier minified.
2018-09-05 15:08:40 +02:00

38 lines
697 B
JavaScript

class Base {
static getThis() {
return babelHelpers.classStaticPrivateFieldSpecGet(this, Base, _foo);
}
static updateThis(val) {
return babelHelpers.classStaticPrivateFieldSpecSet(this, Base, _foo, val);
}
static getClass() {
return babelHelpers.classStaticPrivateFieldSpecGet(Base, Base, _foo);
}
static updateClass(val) {
return babelHelpers.classStaticPrivateFieldSpecSet(Base, Base, _foo, val);
}
}
var _foo = {
writable: true,
value: 1
};
class Sub1 extends Base {
static update(val) {
return babelHelpers.classStaticPrivateFieldSpecSet(this, Sub1, _foo2, val);
}
}
var _foo2 = {
writable: true,
value: 2
};
class Sub2 extends Base {}