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var BUGNUMBER = 1180306;
var summary = 'Array.from should close iterator on error';
print(BUGNUMBER + ": " + summary);
function test(ctor, { mapVal=undefined,
nextVal=undefined,
nextThrowVal=undefined,
modifier=undefined,
exceptionVal=undefined,
exceptionType=undefined,
closed=true }) {
let iterable = {
closed: false,
[Symbol.iterator]() {
let iterator = {
first: true,
next() {
if (this.first) {
this.first = false;
if (nextThrowVal)
throw nextThrowVal;
return nextVal;
}
return { value: undefined, done: true };
},
return() {
iterable.closed = true;
return {};
}
};
if (modifier)
modifier(iterator, iterable);
return iterator;
}
};
if (exceptionVal) {
let caught = false;
try {
ctor.from(iterable, mapVal);
} catch (e) {
assertEq(e, exceptionVal);
caught = true;
}
assertEq(caught, true);
} else if (exceptionType) {
assertThrowsInstanceOf(() => ctor.from(iterable, mapVal), exceptionType);
} else {
ctor.from(iterable, mapVal);
}
assertEq(iterable.closed, closed);
}
// == Error cases with close ==
// ES 2017 draft 22.1.2.1 step 5.e.i.1.
// Cannot test.
// ES 2017 draft 22.1.2.1 step 5.e.vi.2.
test(Array, {
mapVal: () => { throw "map throws"; },
nextVal: { value: 1, done: false },
exceptionVal: "map throws",
closed: true,
});
// ES 2017 draft 22.1.2.1 step 5.e.ix.
class MyArray extends Array {
constructor() {
return new Proxy({}, {
defineProperty() {
throw "defineProperty throws";
}
});
}
}
test(MyArray, {
nextVal: { value: 1, done: false },
exceptionVal: "defineProperty throws",
closed: true,
});
// ES 2021 draft 7.4.6 step 5.
// if GetMethod fails, the thrown value should be ignored.
test(MyArray, {
nextVal: { value: 1, done: false },
modifier: (iterator, iterable) => {
Object.defineProperty(iterator, "return", {
get: function() {
iterable.closed = true;
throw "return getter throws";
}
});
},
exceptionVal: "defineProperty throws",
closed: true,
});
test(MyArray, {
nextVal: { value: 1, done: false },
modifier: (iterator, iterable) => {
Object.defineProperty(iterator, "return", {
get: function() {
iterable.closed = true;
return "non object";
}
});
},
exceptionVal: "defineProperty throws",
closed: true,
});
test(MyArray, {
nextVal: { value: 1, done: false },
modifier: (iterator, iterable) => {
Object.defineProperty(iterator, "return", {
get: function() {
iterable.closed = true;
// Non callable.
return {};
}
});
},
exceptionVal: "defineProperty throws",
closed: true,
});
// ES 2017 draft 7.4.6 steps 6.
// if return method throws, the thrown value should be ignored.
test(MyArray, {
nextVal: { value: 1, done: false },
modifier: (iterator, iterable) => {
iterator.return = function() {
iterable.closed = true;
throw "return throws";
};
},
exceptionVal: "defineProperty throws",
closed: true,
});
test(MyArray, {
nextVal: { value: 1, done: false },
modifier: (iterator, iterable) => {
iterator.return = function() {
iterable.closed = true;
return "non object";
};
},
exceptionVal: "defineProperty throws",
closed: true,
});
// == Error cases without close ==
// ES 2017 draft 22.1.2.1 step 5.e.iii.
test(Array, {
nextThrowVal: "next throws",
exceptionVal: "next throws",
closed: false,
});
test(Array, {
nextVal: { value: {}, get done() { throw "done getter throws"; } },
exceptionVal: "done getter throws",
closed: false,
});
// ES 2017 draft 22.1.2.1 step 5.e.v.
test(Array, {
nextVal: { get value() { throw "value getter throws"; }, done: false },
exceptionVal: "value getter throws",
closed: false,
});
// == Successful cases ==
test(Array, {
nextVal: { value: 1, done: false },
closed: false,
});
if (typeof reportCompare === 'function')
reportCompare(true, true);