mirror of
https://github.com/RGBCube/serenity
synced 2025-05-16 06:25:01 +00:00
e6d920d87d
We now care (a little bit) about the "configurable" and "writable" property attributes. Property attributes are stored together with the property name in the Shape object. Forward transitions are not attribute-savvy and will cause poor Shape reuse in the case of multiple same-name properties with different attributes. Oh, and this patch also adds Object.getOwnPropertyDescriptor() :^)
39 lines
973 B
JavaScript
39 lines
973 B
JavaScript
function assert(x) { if (!x) throw 1; }
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try {
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var o = {};
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Object.defineProperty(o, "foo", { value: 1, writable: false, enumerable: false });
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assert(o.foo === 1);
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o.foo = 2;
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assert(o.foo === 1);
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var d = Object.getOwnPropertyDescriptor(o, "foo");
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assert(d.configurable === false);
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assert(d.enumerable === false);
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assert(d.writable === false);
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assert(d.value === 1);
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Object.defineProperty(o, "bar", { value: "hi", writable: true, enumerable: true });
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assert(o.bar === "hi");
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o.bar = "ho";
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assert(o.bar === "ho");
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d = Object.getOwnPropertyDescriptor(o, "bar");
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assert(d.configurable === false);
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assert(d.enumerable === true);
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assert(d.writable === true);
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assert(d.value === "ho");
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try {
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Object.defineProperty(o, "bar", { value: "xx", enumerable: false });
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} catch (e) {
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assert(e.name === "TypeError");
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}
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console.log("PASS");
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} catch (e) {
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console.log(e)
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}
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