When Zone patches Promise, it uses ZoneAwarePromise. The new Promise.try API was undefined on ZoneAwarePromise, making it unavailable when zone was present. This change gracefully passes through Promise.try to the native Promise implementation, if available, without patching it to execute in the right zone (our stance is not to add new patches but avoid destructively making new APIs unavailable).
Fixes#67057
In the original `Promise` impelmentation, zone.js follow the spec from
https://promisesaplus.com/#point-51.
```
const p1 = Promise.resolve(1);
const p2 = Promise.resolve(p1);
p1 === p2; // false
```
in this case, `p2` should be the same status with `p1` but they are
still different instances.
And for some edge case.
```
class MyPromise extends Promise {
constructor(sub) {
super((res) => res(null));
this.sub = sub;
}
then(onFufilled, onRejected) {
this.sub.then(onFufilled, onRejected);
}
}
const p1 = new Promise(setTimeout(res), 100);
const myP = new MyPromise(p1);
const r = await myP;
r === 1; // false
```
So in the above code, `myP` is not the same instance with `p1`,
and since `myP` is resolved in constructor, so `await myP` will
just pass without waiting for `p1`.
And in the current `tc39` spec here https://tc39.es/ecma262/multipage/control-abstraction-objects.html#sec-promise-resolve
`Promise.resolve(subP)` should return `subP`.
```
const p1 = Promise.resolve(1);
const p2 = Promise.resolve(p1);
p1 === p2; // true
```
So the above `MyPromise` can wait for the `p1` correctly.
PR Close#53423
* Adjusts tests to no longer rely on CommonJS features. Switches them to
ESM
* Updates test initialization files to not double-initialize Jasmine now
that bootstrap files are loaded after Jasmine. The `jasmine.boot`
setup was hacky from `rules_nodejs` and will break in the future
regardless if we e.g. use `rules_js` with actual unmodified `jasmine`.
PR Close#48521
The native promise implementation logs unhandled promise rejections after `onFinally`
has been called. We may rely on the `scheduledByFinally` argument, which is `false` by
default, to avoid creating a breaking change; this will also allow us to reduce the number of
changes. The `finally` function should not silence unhandled promise rejections, because
they're not silenced in any implementation. If the `scheduleResolveOrReject` is called within
the `finally` we won't clear unhandled rejections. We'll keep the same behaviour if the
`scheduleResolveOrReject` is called within the `then`.
PR Close#43206
PR Close#45449
Close#44913
The following case is not handled correctly by `zone.js`.
```
const delayedPromise = new Promise((resolve) => {
setTimeout(resolve, 1, 'timeout');
});
new Promise((resolve) => {
resolve(delayedPromise);
resolve('second call');
}).then(console.log);
```
It should output `timeout`, since the promise is resolved by the
1st resolve, the `second call` should be ignored.
So this is a bug that the original implementation not ensure the
`resolve` is only called once.
PR Close#45283
We must read `Symbol.species` safely because `this` may be anything. For instance, `this`
may be an object without a prototype (created through `Object.create(null)`); thus
`this.constructor` will be undefined. One of the use cases is SystemJS creating
prototype-less objects (modules) via `Object.create(null)`. The SystemJS creates an empty
object and copies promise properties into that object (within the `getOrCreateLoad`
function). The zone.js then checks if the resolved value has the `then` method and invokes
it with the `value` context. Otherwise, this will throw an error: `TypeError: Cannot read
properties of undefined (reading 'Symbol(Symbol.species)')`.
PR Close#45369
This PR updates Angular to compile with TypeScript 3.6 while retaining
compatibility with TS3.5. We achieve this by inserting several `as any`
casts for compatiblity around `ts.CompilerHost` APIs.
PR Close#32908
Alan Agius