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// Tests for for-of loops + `using` at the top level of a module, in particular
// cases where the for-of head has no lexical declarations.
let log = [];
function makeIter() {
let i = 0;
return {
[Symbol.iterator]() {
return this;
},
next() {
return {value: i, done: i++ >= 3};
},
return() {
log.push("it.return");
return {done: true};
},
};
}
function makeRes() {
return {disposed: false,
[Symbol.dispose]() {
log.push("dispose");
this.disposed = true;
}};
}
function makeAsyncRes() {
return {disposed: false,
[Symbol.asyncDispose]() {
log.push("asyncDispose");
this.disposed = true;
return Promise.resolve();
}};
}
function test(source, expected) {
log = [];
const m = parseModule(source);
moduleLoadAndLink(m);
moduleEvaluate(m).catch(e => log.push(`rejected: ${e.message}`));
drainJobQueue();
assertEq(log.join(","), expected);
}
// break, and the resource is still live after the loop.
test(`
let x;
using a = makeRes();
for (x of makeIter()) {
break;
}
assertEq(a.disposed, false);
log.push("after loop");
`, "it.return,after loop,dispose");
// Same, but the `using` is in a block instead of the module's top-level scope.
test(`
let x;
{
using a = makeRes();
for (x of makeIter()) {
break;
}
log.push("after loop");
}
log.push("left block");
`, "it.return,after loop,dispose,left block");
// continue out of an inner for-of crosses the inner loop only.
test(`
let x, y;
using a = makeRes();
outer: for (y of makeIter()) {
for (x of makeIter()) {
continue outer;
}
}
assertEq(a.disposed, false);
`, "it.return,it.return,it.return,dispose");
// The enclosing scope is another for-of head.
test(`
let b;
for (using a of [makeRes(), makeRes()]) {
for (b of makeIter()) {
break;
}
assertEq(a.disposed, false);
}
`, "it.return,dispose,it.return,dispose");
// `using` in the loop body is disposed before IteratorClose.
test(`
let x;
for (x of makeIter()) {
using a = makeRes();
break;
}
`, "dispose,it.return");
// An uncaught exception rejects the module's evaluation promise.
test(`
let x;
using a = makeRes();
for (x of makeIter()) {
throw new Error("err");
}
`, "it.return,dispose,rejected: err");
// Top-level `await using`.
test(`
let x;
await using a = makeAsyncRes();
for (x of makeIter()) {
break;
}
assertEq(a.disposed, false);
log.push("after loop");
`, "it.return,after loop,asyncDispose");