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|
// Copyright 2017 Tooru Fujisawa. All rights reserved.
// This code is governed by the BSD license found in the LICENSE file.
/*---
desc: Execution order for yield* with async iterator and next()
template: default
info: |
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 ? Invoke(iterator, "next", « received.[[Value]] »).
ii. If generatorKind is async, then set innerResult to ? Await(innerResult).
...
iv. Let done be ? IteratorComplete(innerResult).
v. If done is true, then
1. Let resultValue be ? IteratorValue(innerResult).
2. If generatorKind is async, then set resultValue to ? Await(resultValue).
3. Return resultValue.
vi. If generatorKind is async, then let received be AsyncGeneratorYield(? IteratorValue(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).
...
AsyncGeneratorYield ( value )
...
8. Return ! AsyncGeneratorResolve(generator, value, false).
...
flags: [async]
features: [Symbol.iterator, async-iteration, Symbol.asyncIterator]
---*/
//- setup
var log = [];
var obj = {
get [Symbol.iterator]() {
log.push({ name: "get [Symbol.iterator]" });
},
get [Symbol.asyncIterator]() {
log.push({
name: "get [Symbol.asyncIterator]",
thisValue: this
});
return function() {
log.push({
name: "call [Symbol.asyncIterator]",
thisValue: this,
args: [...arguments]
});
var nextCount = 0;
return {
name: "asyncIterator",
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-promise-1",
get then() {
log.push({
name: "get next then (1)",
thisValue: this
});
return function(resolve) {
log.push({
name: "call next then (1)",
thisValue: this,
args: [...arguments]
});
resolve({
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-promise-2",
get then() {
log.push({
name: "get next then (2)",
thisValue: this
});
return function(resolve) {
log.push({
name: "call next then (2)",
thisValue: this,
args: [...arguments]
});
resolve({
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;
}
});
};
}
};
};
}
};
};
}
};
//- body
log.push({ name: "before yield*" });
var v = yield* obj;
log.push({
name: "after yield*",
value: v
});
return "return-value";
//- assertions
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[1].thisValue, obj, "get [Symbol.asyncIterator] thisValue");
assert.sameValue(log[2].name, "call [Symbol.asyncIterator]");
assert.sameValue(log[2].thisValue, obj, "[Symbol.asyncIterator] thisValue");
assert.sameValue(log[2].args.length, 0, "[Symbol.asyncIterator] args.length");
assert.sameValue(log[3].name, "get next");
assert.sameValue(log[3].thisValue.name, "asyncIterator", "get next thisValue");
assert.sameValue(log[4].name, "call next");
assert.sameValue(log[4].thisValue.name, "asyncIterator", "next thisValue");
assert.sameValue(log[4].args.length, 1, "next args.length");
assert.sameValue(log[4].args[0], undefined, "next args[0]");
assert.sameValue(log[5].name, "get next then (1)");
assert.sameValue(log[5].thisValue.name, "next-promise-1", "get next then thisValue");
assert.sameValue(log[6].name, "call next then (1)");
assert.sameValue(log[6].thisValue.name, "next-promise-1", "next then thisValue");
assert.sameValue(log[6].args.length, 2, "next then args.length");
assert.sameValue(typeof log[6].args[0], "function", "next then args[0]");
assert.sameValue(typeof log[6].args[1], "function", "next then args[1]");
assert.sameValue(log[7].name, "get next done (1)");
assert.sameValue(log[7].thisValue.name, "next-result-1", "get next done thisValue");
assert.sameValue(log[8].name, "get next value (1)");
assert.sameValue(log[8].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, 9, "log.length");
iter.next("next-arg-2").then(v => {
assert.sameValue(log[9].name, "call next");
assert.sameValue(log[9].thisValue.name, "asyncIterator", "next thisValue");
assert.sameValue(log[9].args.length, 1, "next args.length");
assert.sameValue(log[9].args[0], "next-arg-2", "next args[0]");
assert.sameValue(log[10].name, "get next then (2)");
assert.sameValue(log[10].thisValue.name, "next-promise-2", "get next then thisValue");
assert.sameValue(log[11].name, "call next then (2)");
assert.sameValue(log[11].thisValue.name, "next-promise-2", "next then thisValue");
assert.sameValue(log[11].args.length, 2, "next then args.length");
assert.sameValue(typeof log[11].args[0], "function", "next then args[0]");
assert.sameValue(typeof log[11].args[1], "function", "next then args[1]");
assert.sameValue(log[12].name, "get next done (2)");
assert.sameValue(log[12].thisValue.name, "next-result-2", "get next done thisValue");
assert.sameValue(log[13].name, "get next value (2)");
assert.sameValue(log[13].thisValue.name, "next-result-2", "get next value thisValue");
assert.sameValue(log[14].name, "after yield*");
assert.sameValue(log[14].value, "next-value-2");
assert.sameValue(v.value, "return-value");
assert.sameValue(v.done, true);
assert.sameValue(log.length, 15, "log.length");
}).then($DONE, $DONE);
}).catch($DONE);
|
