// Ensure we are in JIT code and attach IC stubs.
const iterations = 50;
function testFoo(obj, kind, expected) {
for (var i = 0; i < iterations; i++) {
obj.foo = i;
is(obj.foo, (expected === undefined) ? i : expected, "Looking up an expando should work - " + kind);
}
}
function getPropTests(obj) {
// Start with a plain data property.
obj.foo = "bar";
testFoo(obj, "plain");
// Now change it to a scripted getter/setter. var count = 0; var getterSetterVal = 0; Object.defineProperty(obj, "foo", {configurable: true, get() {
is(this, obj, "Getter should have the proxy as |this|");
is(arguments.length, 0, "Shouldn't pass arguments to getters");
count++;
return getterSetterVal;
}, set(v) {
is(this, obj, "Setter should have the proxy as |this|");
is(arguments.length, 1, "Should pass 1 argument to setters");
getterSetterVal = v;
count++;
}});
testFoo(obj, "scripted getter/setter");
is(count, iterations * 2, "Should have called the getter/setter enough times");
// Now try a native getter/setter. Object.defineProperty(obj, "foo", {get: Math.abs, set: Math.abs, configurable: true});
testFoo(obj, "native getter/setter", NaN);
}
function getElemTests(obj) {
// Define two expando properties, then test inline caches for obj[prop]
// correctly guard on prop being the same. var count = 0, getterSetterVal = 0;
obj.elem1 = 1; Object.defineProperty(obj, "elem2", {
get() { count++; return getterSetterVal; },
set(v) { getterSetterVal = v; count++; },
});
for (var i = 0; i < iterations; i++) { var prop = ((i & 1) == 0) ? "elem1" : "elem2";
obj[prop] = i;
is(obj[prop], i, "Should return correct property value");
}
is(count, iterations, "Should have called the getter/setter enough times");
}
var directExpando = document.getElementsByTagName("*"); var indirectExpando = document.getElementById("theform");
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