@Override
        public void run() {
            if (HelperPromise.this.cancelled.get()) {
                return;
            }
            try {
                this.promise.complete(this.function.apply(this.t));
            } catch (Throwable t) {
                HelperExceptions.reportPromise(t);
                this.promise.completeExceptionally(t);
            }
        }
The completable future backing this promise
helper/src/main/java/me/lucko/helper/promise/HelperPromise.java