NextStreamValueFuture

next_stream_value_future.dart

import 'dart:async';

class NextStreamValueFuture<T> with Future<T> {
  NextStreamValueFuture(this.stream) {
    late final StreamSubscription<T> subscription;
    subscription = stream.listen(
      (value) {
        completer.complete(value);
        subscription.cancel();
      },
      onError: completer.completeError,
    );
  }

  final completer = Completer<T>();
  final Stream<T> stream;

  @override
  Stream<T> asStream() => completer.future.asStream();

  @override
  Future<T> catchError(Function onError, {bool Function(Object error)? test}) => completer.future.catchError(onError, test: test);

  @override
  Future<R> then<R>(FutureOr<R> Function(T value) onValue, {Function? onError}) => completer.future.then(onValue, onError: onError);

  @override
  Future<T> timeout(Duration timeLimit, {FutureOr<T> Function()? onTimeout}) => completer.future.timeout(timeLimit, onTimeout: onTimeout);

  @override
  Future<T> whenComplete(FutureOr<void> Function() action) => completer.future.whenComplete(action);
}