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// Object operations are performed in the right order, as observed by proxies.
let log = [];
function LoggingProxyHandlerWrapper(name, handler={}) {
return new Proxy(handler, {
get(t, id) {
let method = handler[id];
return function (...args) {
log.push([name + "." + id, ...args.filter(v => typeof v !== "object")]);
if (method === undefined)
return Reflect[id].apply(null, args);
return method.apply(this, args);
};
}
});
}
function LoggingProxy(name, target) {
return new Proxy(target, new LoggingProxyHandlerWrapper(name));
}
let proto = {x: 44};
let proto_proxy = new LoggingProxy("proto", proto);
let unscopables = {x: true};
let unscopables_proxy = new LoggingProxy("unscopables", {x: true});
let env = Object.create(proto_proxy, {
[Symbol.unscopables]: { value: unscopables_proxy }
});
let env_proxy = new LoggingProxy("env", env);
let x = 11;
function f() {
with (env_proxy)
return x;
}
assertEq(f(), 11);
assertDeepEq(log, [
["env.has", "x"],
["proto.has", "x"],
["env.get", Symbol.unscopables],
["unscopables.get", "x"]
]);
reportCompare(0, 0);