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// Receiver shadows
(function() {
function check(p) { return p.x; }
let a = { x: "a" };
let b = { __proto__: a };
let c = { __proto__: b };
let d = { __proto__: c };
assertEq(check(d), "a");
assertEq(check(d), "a");
d.x = "d";
assertEq(check(d), "d");
})();
// Intermediate proto shadows
(function() {
function check(p) { return p.x; }
let a = { x: "a" };
let b = { __proto__: a };
let c = { __proto__: b };
let d = { __proto__: c };
assertEq(check(d), "a");
assertEq(check(d), "a");
c.x = "c";
assertEq(check(d), "c");
})();
// Receiver proto changes
(function() {
function check(p) { return p.x; }
let a = { x: "a" };
let b = { __proto__: a };
let c = { __proto__: b };
let d = { __proto__: c };
assertEq(check(d), "a");
assertEq(check(d), "a");
d.__proto__ = { x: "?" };
assertEq(check(d), "?");
})();
// Intermediate proto changes
(function() {
function check(p) { return p.x; }
let a = { x: "a" };
let b = { __proto__: a };
let c = { __proto__: b };
let d = { __proto__: c };
assertEq(check(d), "a");
assertEq(check(d), "a");
c.__proto__ = { x: "?" };
assertEq(check(d), "?");
})();
// Uncacheable holder proto
(function() {
function check(p) { return p.x; }
function Base() { this.x = "a"; }
let a = new Base;
a.__proto__ = new Object;
let b = { __proto__: a };
let c = { __proto__: b };
let d = { __proto__: c };
assertEq(check(d), "a");
assertEq(check(d), "a");
b.__proto__ = { x: "?" };
assertEq(check(d), "?");
})();
// Uncacheable intermediate proto
(function() {
function check(p) { return p.x; }
function Base() { this.x = "a"; }
function Node() { }
let a = new Base;
let b = new Node; b.__proto__ = a;
let c = { __proto__: b };
let d = { __proto__: c };
assertEq(check(d), "a");
assertEq(check(d), "a");
b.__proto__ = { x: "?" };
assertEq(check(d), "?");
})();
// Uncacheable receiver proto
(function() {
function check(p) { return p.x; }
function Base() { this.x = "a"; }
function Node() { }
let a = new Base;
let b = { __proto__: a };
let c = { __proto__: b };
let d = new Node; d.__proto__ = c;
assertEq(check(d), "a");
assertEq(check(d), "a");
d.__proto__ = { x: "?" };
assertEq(check(d), "?");
})();
// Uncacheable receiver proto (only receiver / holder)
(function() {
function check(p) { return p.x; }
function Base() { this.x = "a"; }
function Node() { }
let a = new Base;
let b = new Node; b.__proto__ = a;
assertEq(check(b), "a");
assertEq(check(b), "a");
b.__proto__ = { x: "?" };
assertEq(check(b), "?");
})();