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// |reftest| async
// Copyright (C) 2023 Igalia, S.L. All rights reserved.
// This code is governed by the BSD license found in the LICENSE file.
/*---
esid: sec-array.fromasync
description: >
Order of user-observable operations on a custom this-value and its instances
includes: [compareArray.js, asyncHelpers.js]
flags: [async]
features: [Array.fromAsync]
---*/
function formatPropertyName(propertyKey, objectName = "") {
switch (typeof propertyKey) {
case "symbol":
if (Symbol.keyFor(propertyKey) !== undefined) {
return `${objectName}[Symbol.for('${Symbol.keyFor(propertyKey)}')]`;
} else if (propertyKey.description.startsWith('Symbol.')) {
return `${objectName}[${propertyKey.description}]`;
} else {
return `${objectName}[Symbol('${propertyKey.description}')]`
}
case "string":
if (propertyKey !== String(Number(propertyKey)))
return objectName ? `${objectName}.${propertyKey}` : propertyKey;
// fall through
default:
// integer or string integer-index
return `${objectName}[${propertyKey}]`;
}
}
asyncTest(async function () {
const expectedCalls = [
"construct MyArray",
"defineProperty A[0]",
"defineProperty A[1]",
"set A.length"
];
const actualCalls = [];
function MyArray(...args) {
actualCalls.push("construct MyArray");
return new Proxy(Object.create(null), {
set(target, key, value) {
actualCalls.push(`set ${formatPropertyName(key, "A")}`);
return Reflect.set(target, key, value);
},
defineProperty(target, key, descriptor) {
actualCalls.push(`defineProperty ${formatPropertyName(key, "A")}`);
return Reflect.defineProperty(target, key, descriptor);
}
});
}
let result = await Array.fromAsync.call(MyArray, [1, 2]);
assert.compareArray(expectedCalls, actualCalls, "order of operations for array argument");
actualCalls.splice(0); // reset
const expectedCallsForArrayLike = [
"construct MyArray",
"defineProperty A[0]",
"defineProperty A[1]",
"set A.length"
];
result = await Array.fromAsync.call(MyArray, {
length: 2,
0: 1,
1: 2
});
assert.compareArray(expectedCallsForArrayLike, actualCalls, "order of operations for array-like argument");
});