If the number of progress bar exceed terminal height, newlines appears instead of clearing itself.

[pombadev]

Similar to #144 , if progress bars exceeds terminal's height i.e if there are more progress bars than it is able fit in visible at once, newlines are created. Fix provided in #144 doesn't help either.

Reproduction steps:

indicatif = "0.17.2"

use std::thread;
use std::time::Duration;

use indicatif::{MultiProgress, ProgressBar, ProgressStyle};

fn main() {
    let m = MultiProgress::new();
    let sty = ProgressStyle::with_template(
        "[{elapsed_precise}] {bar:40.cyan/blue} {pos:>7}/{len:7} {msg}",
    )
    .unwrap()
    .progress_chars("##-");

    m.println("starting!").unwrap();

    let mut h = vec![];

    for _ in 0..50 {
        let pb = m.add(ProgressBar::new(128));
        pb.set_style(sty.clone());

        let m_clone = m.clone();
        let h1 = thread::spawn(move || {
            for i in 0..128 {
                pb.set_message(format!("item #{}", i + 1));
                pb.inc(1);
                thread::sleep(Duration::from_millis(50));
            }
            m_clone.println("pb1 is done!").unwrap();
            pb.finish_with_message("done");
        });

        h.push(h1);
    }

    for k in h {
        k.join().unwrap();
    }

    // m.clear().unwrap();
}

Use this code and run it

• in a terminal with height tall enough that it is able to display all progress bars at once, no issues.
• in a terminal with reduced height so that all progress bars are not visible at once, newlines occurs.

Example

[djc]

@chris-laplante any ideas?

[chris-laplante]

@chris-laplante any ideas?

Yes, I think we can handle this like how tqdm handles it: https://github.com/tqdm/tqdm/issues/918. Basically, just like how we autodetect terminal width we should also look at terminal height and only try to draw as many progress bars as will fit on the screen.

[peschu123]

I was playing around with async and I think I have the same problem with the code below.

It looks quite a bit more weird (in the error case). Also I use multiple progress bars for tasks and one main progress bar at the bottom to track overall progress.

Just change the "ITEMS" variable to a lower or higher value.

use indicatif::{MultiProgress, ProgressBar, ProgressStyle};
use rand::prelude::*;
use std::convert::TryInto;
use tokio::task::JoinSet;
use tokio::time::{sleep, Duration};
use uuid::Uuid;

#[tokio::main]
async fn main() {
    const ITEMS: usize = 30;
    let uuids: Vec<(Uuid, usize)> = (0..ITEMS)
        .into_iter()
        // generate new uuid and an index
        .map(|x| (Uuid::new_v4(), x))
        .collect();

    let multi_pb = MultiProgress::new();
    let items_u64: u64 = ITEMS.try_into().unwrap();
    let main_pb = multi_pb.add(ProgressBar::new(items_u64));
    main_pb.set_style(
        ProgressStyle::with_template(
            "[{elapsed_precise}] {bar:40.cyan/blue} {pos:>7}/{len:7} {msg}",
        )
        .unwrap()
        .progress_chars("##-"),
    );

    main_pb.set_message("total  ");
    // Make the main progress bar render immediately rather than waiting for the
    // first task to finish.
    main_pb.tick();

    let mut set = JoinSet::new();
    for (uuid, index) in uuids {
        let steps = 100;
        let task_pb = multi_pb.insert_before(&main_pb, ProgressBar::new(steps));
        task_pb.set_style(
            ProgressStyle::with_template(
                "[{elapsed_precise}] {bar:40.cyan/blue} {pos:>7}/{len:7} {msg}",
            )
            .unwrap()
            .progress_chars("##-"),
        );
        set.spawn(do_stuff(uuid, index, steps, task_pb));
    }

    let mut seen = [false; ITEMS];
    while let Some(res) = set.join_next().await {
        let idx = res.unwrap();
        seen[idx] = true;
        main_pb.inc(1);
    }
    main_pb.finish();
}

async fn do_stuff(uuid: Uuid, index: usize, steps: u64, task_pb: ProgressBar) -> usize {
    let msg = format!("app #{} with id:{}", index, uuid);
    task_pb.set_message(msg.clone());

    // calculate "tick size" for progress bar to use with sleep (millisecs / steps)
    let num = rand::thread_rng().gen_range(steps..=10000);
    let tick = num / steps;

    for _ in 0..steps {
        sleep(Duration::from_millis(tick)).await;
        task_pb.inc(1);
    }
    let msg = format!("DONE {}", &msg);
    task_pb.finish_with_message(msg);
    index
}