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// |reftest| shell-option(--enable-new-set-methods) skip-if(!Set.prototype.isSubsetOf)
assertEq(typeof Set.prototype.isSubsetOf, "function");
assertDeepEq(Object.getOwnPropertyDescriptor(Set.prototype.isSubsetOf, "length"), {
value: 1, writable: false, enumerable: false, configurable: true,
});
assertDeepEq(Object.getOwnPropertyDescriptor(Set.prototype.isSubsetOf, "name"), {
value: "isSubsetOf", writable: false, enumerable: false, configurable: true,
});
const emptySet = new Set();
const emptySetLike = new SetLike();
const emptyMap = new Map();
function asMap(values) {
return new Map(values.map(v => [v, v]));
}
// Empty set is a subset of the empty set.
assertEq(emptySet.isSubsetOf(emptySet), true);
assertEq(emptySet.isSubsetOf(emptySetLike), true);
assertEq(emptySet.isSubsetOf(emptyMap), true);
// Test native Set, Set-like, and Map objects.
for (let values of [
[], [1], [1, 2], [1, true, null, {}],
]) {
// Subset operation with an empty set.
assertEq(new Set(values).isSubsetOf(emptySet), values.length === 0);
assertEq(new Set(values).isSubsetOf(emptySetLike), values.length === 0);
assertEq(new Set(values).isSubsetOf(emptyMap), values.length === 0);
assertEq(emptySet.isSubsetOf(new Set(values)), true);
assertEq(emptySet.isSubsetOf(new SetLike(values)), true);
assertEq(emptySet.isSubsetOf(asMap(values)), true);
// Two sets with the exact same values.
assertEq(new Set(values).isSubsetOf(new Set(values)), true);
assertEq(new Set(values).isSubsetOf(new SetLike(values)), true);
assertEq(new Set(values).isSubsetOf(asMap(values)), true);
// Subset operation of the same set object.
let set = new Set(values);
assertEq(set.isSubsetOf(set), true);
}
// Check property accesses are in the correct order.
{
let log = [];
let sizeValue = 0;
let {proxy: keysIter} = LoggingProxy({
next() {
log.push("next()");
return {done: true};
}
}, log);
let {proxy: setLike} = LoggingProxy({
size: {
valueOf() {
log.push("valueOf()");
return sizeValue;
}
},
has() {
throw new Error("Unexpected call to |has| method");
},
keys() {
log.push("keys()");
return keysIter;
},
}, log);
assertEq(emptySet.isSubsetOf(setLike), true);
assertEqArray(log, [
"[[get]]", "size",
"valueOf()",
"[[get]]", "has",
"[[get]]", "keys",
]);
}
// Check input validation.
{
let log = [];
const nonCallable = {};
let sizeValue = 0;
let {proxy: setLike, obj: setLikeObj} = LoggingProxy({
size: {
valueOf() {
log.push("valueOf()");
return sizeValue;
}
},
has() {
throw new Error("Unexpected call to |has| method");
},
keys() {
throw new Error("Unexpected call to |keys| method");
},
}, log);
// Change |keys| to a non-callable value.
setLikeObj.keys = nonCallable;
log.length = 0;
assertThrowsInstanceOf(() => emptySet.isSubsetOf(setLike), TypeError);
assertEqArray(log, [
"[[get]]", "size",
"valueOf()",
"[[get]]", "has",
"[[get]]", "keys",
]);
// Change |has| to a non-callable value.
setLikeObj.has = nonCallable;
log.length = 0;
assertThrowsInstanceOf(() => emptySet.isSubsetOf(setLike), TypeError);
assertEqArray(log, [
"[[get]]", "size",
"valueOf()",
"[[get]]", "has",
]);
// Change |size| to NaN.
sizeValue = NaN;
log.length = 0;
assertThrowsInstanceOf(() => emptySet.isSubsetOf(setLike), TypeError);
assertEqArray(log, [
"[[get]]", "size",
"valueOf()",
]);
// Change |size| to undefined.
sizeValue = undefined;
log.length = 0;
assertThrowsInstanceOf(() => emptySet.isSubsetOf(setLike), TypeError);
assertEqArray(log, [
"[[get]]", "size",
"valueOf()",
]);
}
// Doesn't accept Array as an input.
assertThrowsInstanceOf(() => emptySet.isSubsetOf([]), TypeError);
// Works with Set subclasses.
{
class MySet extends Set {}
let myEmptySet = new MySet;
assertEq(emptySet.isSubsetOf(myEmptySet), true);
assertEq(myEmptySet.isSubsetOf(myEmptySet), true);
assertEq(myEmptySet.isSubsetOf(emptySet), true);
}
// Doesn't access any properties on the this-value.
{
let log = [];
let {proxy: setProto} = LoggingProxy(Set.prototype, log);
let set = new Set([]);
Object.setPrototypeOf(set, setProto);
assertEq(Set.prototype.isSubsetOf.call(set, emptySet), true);
assertEqArray(log, []);
}
// Throws a TypeError when the this-value isn't a Set object.
for (let thisValue of [
null, undefined, true, "", {}, new Map, new Proxy(new Set, {}),
]) {
assertThrowsInstanceOf(() => Set.prototype.isSubsetOf.call(thisValue, emptySet), TypeError);
}
// Doesn't call |has| when this-value has more elements.
{
let set = new Set([1, 2, 3]);
for (let size of [0, 1, 2]) {
let setLike = {
size,
has() {
throw new Error("Unexpected call to |has| method");
},
keys() {
throw new Error("Unexpected call to |keys| method");
},
};
assertEq(set.isSubsetOf(setLike), false);
}
}
// Test when this-value is modified during iteration.
{
let set = new Set([1, 2, 3]);
let seen = new Set();
let setLike = {
size: 100,
has(v) {
assertEq(arguments.length, 1);
assertEq(this, setLike);
assertEq(set.has(v), true);
assertEq(seen.has(v), false);
seen.add(v);
// Delete the current element.
set.delete(v);
return true;
},
keys() {
throw new Error("Unexpected call to |keys| method");
},
};
assertEq(set.isSubsetOf(setLike), true);
assertSetContainsExactOrderedItems(set, []);
assertSetContainsExactOrderedItems(seen, [1, 2, 3]);
}
{
let set = new Set([1]);
let seen = new Set();
let newKeys = [2, 3, 4, 5];
let setLike = {
size: 100,
has(v) {
assertEq(arguments.length, 1);
assertEq(this, setLike);
assertEq(set.has(v), true);
assertEq(seen.has(v), false);
seen.add(v);
// Delete the current element.
set.delete(v);
// Add new elements.
if (newKeys.length) {
set.add(newKeys.shift());
}
return true;
},
keys() {
throw new Error("Unexpected call to |keys| method");
},
};
assertEq(set.isSubsetOf(setLike), true);
assertSetContainsExactOrderedItems(set, []);
assertSetContainsExactOrderedItems(seen, [1, 2, 3, 4, 5]);
assertEq(newKeys.length, 0);
}
{
let set = new Set([1, 2, 3]);
let seen = new Set();
let deleted = false;
let setLike = {
size: 100,
has(v) {
assertEq(arguments.length, 1);
assertEq(this, setLike);
assertEq(set.has(v), true);
assertEq(seen.has(v), false);
seen.add(v);
if (!deleted) {
assertEq(v, 1);
set.delete(2);
deleted = true;
}
return true;
},
keys() {
throw new Error("Unexpected call to |keys| method");
},
};
assertEq(set.isSubsetOf(setLike), true);
assertSetContainsExactOrderedItems(set, [1, 3]);
assertSetContainsExactOrderedItems(seen, [1, 3]);
assertEq(deleted, true);
}
// Tests which modify any built-ins should appear last, because modifications may disable
// optimised code paths.
// Doesn't call the built-in |Set.prototype.{has, keys, size}| functions.
const SetPrototypeHas = Object.getOwnPropertyDescriptor(Set.prototype, "has");
const SetPrototypeKeys = Object.getOwnPropertyDescriptor(Set.prototype, "keys");
const SetPrototypeSize = Object.getOwnPropertyDescriptor(Set.prototype, "size");
delete Set.prototype.has;
delete Set.prototype.keys;
delete Set.prototype.size;
try {
let set = new Set([1, 2, 3]);
let other = new SetLike([1, 2, 3]);
assertEq(set.isSubsetOf(other), true);
} finally {
Object.defineProperty(Set.prototype, "has", SetPrototypeHas);
Object.defineProperty(Set.prototype, "keys", SetPrototypeKeys);
Object.defineProperty(Set.prototype, "size", SetPrototypeSize);
}
if (typeof reportCompare === "function")
reportCompare(true, true);