Stream<T>.fromFuture constructor
Creates a new single-subscription stream from the future.
When the future completes, the stream will fire one event, either data or error, and then close with a done-event.
Implementation
factory Stream.fromFuture(Future<T> future) {
// Use the controller's buffering to fill in the value even before
// the stream has a listener. For a single value, it's not worth it
// to wait for a listener before doing the `then` on the future.
_StreamController<T> controller =
new _SyncStreamController<T>(null, null, null, null);
future.then((value) {
controller._add(value);
controller._closeUnchecked();
}, onError: (error, stackTrace) {
controller._addError(error, stackTrace);
controller._closeUnchecked();
});
return controller.stream;
}