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// This file was procedurally generated from the following sources:
// - src/async-generators/yield-star-sync-next.case
// - src/async-generators/default/async-obj-method.template
/*---
description: execution order for yield* with sync iterator and next() (Async generator method)
esid: prod-AsyncGeneratorMethod
features: [Symbol.iterator, async-iteration, Symbol.asyncIterator]
flags: [generated, async]
info: |
Async Generator Function Definitions
AsyncGeneratorMethod :
async [no LineTerminator here] * PropertyName ( UniqueFormalParameters ) { AsyncGeneratorBody }
YieldExpression: yield * AssignmentExpression
...
2. Let value be ? GetValue(exprRef).
3. Let generatorKind be ! GetGeneratorKind().
4. Let iterator be ? GetIterator(value, generatorKind).
5. Let received be NormalCompletion(undefined).
6. Repeat
a. If received.[[Type]] is normal, then
i. Let innerResult be ? IteratorNext(iterator, received.[[Value]]).
ii. Let innerResult be ? Invoke(iterator, "next",
« received.[[Value]] »).
iii. If generatorKind is async, then set innerResult to
? Await(innerResult).
...
v. Let done be ? IteratorComplete(innerResult).
vi. If done is true, then
1. Return ? IteratorValue(innerResult).
vii. Let received be GeneratorYield(innerResult).
...
GetIterator ( obj [ , hint ] )
...
3. If hint is async,
a. Set method to ? GetMethod(obj, @@asyncIterator).
b. If method is undefined,
i. Let syncMethod be ? GetMethod(obj, @@iterator).
ii. Let syncIterator be ? Call(syncMethod, obj).
iii. Return ? CreateAsyncFromSyncIterator(syncIterator).
...
%AsyncFromSyncIteratorPrototype%.next ( value )
...
5. Let nextResult be IteratorNext(syncIterator, value).
...
7. Let nextValue be IteratorValue(nextResult).
...
9. Let nextDone be IteratorComplete(nextResult).
...
12. Perform ! Call(valueWrapperCapability.[[Resolve]], undefined,
« nextValue »).
...
14. Set onFulfilled.[[Done]] to nextDone.
15. Perform ! PerformPromiseThen(valueWrapperCapability.[[Promise]],
onFulfilled, undefined, promiseCapability).
...
Async Iterator Value Unwrap Functions
1. Return ! CreateIterResultObject(value, F.[[Done]]).
---*/
var log = [];
var obj = {
get [Symbol.iterator]() {
log.push({
name: "get [Symbol.iterator]",
thisValue: this
});
return function() {
log.push({
name: "call [Symbol.iterator]",
thisValue: this,
args: [...arguments]
});
var nextCount = 0;
return {
name: "syncIterator",
get next() {
log.push({
name: "get next",
thisValue: this
});
return function() {
log.push({
name: "call next",
thisValue: this,
args: [...arguments]
});
nextCount++;
if (nextCount == 1) {
return {
name: "next-result-1",
get value() {
log.push({
name: "get next value (1)",
thisValue: this
});
return "next-value-1";
},
get done() {
log.push({
name: "get next done (1)",
thisValue: this
});
return false;
}
};
}
return {
name: "next-result-2",
get value() {
log.push({
name: "get next value (2)",
thisValue: this
});
return "next-value-2";
},
get done() {
log.push({
name: "get next done (2)",
thisValue: this
});
return true;
}
};
};
}
};
};
},
get [Symbol.asyncIterator]() {
log.push({ name: "get [Symbol.asyncIterator]" });
return null;
}
};
var callCount = 0;
var gen = {
async *method() {
callCount += 1;
log.push({ name: "before yield*" });
var v = yield* obj;
log.push({
name: "after yield*",
value: v
});
return "return-value";
}
}.method;
var iter = gen();
assert.sameValue(log.length, 0, "log.length");
iter.next("next-arg-1").then(v => {
assert.sameValue(log[0].name, "before yield*");
assert.sameValue(log[1].name, "get [Symbol.asyncIterator]");
assert.sameValue(log[2].name, "get [Symbol.iterator]");
assert.sameValue(log[2].thisValue, obj, "get [Symbol.iterator] thisValue");
assert.sameValue(log[3].name, "call [Symbol.iterator]");
assert.sameValue(log[3].thisValue, obj, "[Symbol.iterator] thisValue");
assert.sameValue(log[3].args.length, 0, "[Symbol.iterator] args.length");
assert.sameValue(log[4].name, "get next");
assert.sameValue(log[4].thisValue.name, "syncIterator", "get next thisValue");
assert.sameValue(log[5].name, "call next");
assert.sameValue(log[5].thisValue.name, "syncIterator", "next thisValue");
assert.sameValue(log[5].args.length, 1, "next args.length");
assert.sameValue(log[5].args[0], undefined, "next args[0]");
assert.sameValue(log[6].name, "get next done (1)");
assert.sameValue(log[6].thisValue.name, "next-result-1", "get next done thisValue");
assert.sameValue(log[7].name, "get next value (1)");
assert.sameValue(log[7].thisValue.name, "next-result-1", "get next value thisValue");
assert.sameValue(v.value, "next-value-1");
assert.sameValue(v.done, false);
assert.sameValue(log.length, 8, "log.length");
iter.next("next-arg-2").then(v => {
assert.sameValue(log[8].name, "call next");
assert.sameValue(log[8].thisValue.name, "syncIterator", "next thisValue");
assert.sameValue(log[8].args.length, 1, "next args.length");
assert.sameValue(log[8].args[0], "next-arg-2", "next args[0]");
assert.sameValue(log[9].name, "get next done (2)");
assert.sameValue(log[9].thisValue.name, "next-result-2", "get next done thisValue");
assert.sameValue(log[10].name, "get next value (2)");
assert.sameValue(log[10].thisValue.name, "next-result-2", "get next value thisValue");
assert.sameValue(log[11].name, "after yield*");
assert.sameValue(log[11].value, "next-value-2");
assert.sameValue(v.value, "return-value");
assert.sameValue(v.done, true);
assert.sameValue(log.length, 12, "log.length");
}).then($DONE, $DONE);
}).catch($DONE);
assert.sameValue(callCount, 1);
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