pub fn run(&mut self) {
        run_executor(|cx| self.poll_pool(cx))
    }
Run all tasks in the pool to completion.

```
use futures::executor::LocalPool;

let mut pool = LocalPool::new();

// ... spawn some initial tasks using `spawn.spawn()` or `spawn.spawn_local()`

// run *all* tasks in the pool to completion, including any newly-spawned ones.
pool.run();
```

The function will block the calling thread until *all* tasks in the pool
are complete, including any spawned while running existing tasks.
futures-executor/src/local_pool.rs