better progress report during file read

src/main.rs

@@ -5,7 +5,7 @@ use std::time::Instant;
 
 use anyhow::Result;
 use clap::Parser;
-use indicatif::ParallelProgressIterator;
+use indicatif::{ParallelProgressIterator, ProgressBar};
 use kiddo::{SquaredEuclidean, immutable::float::kdtree::ImmutableKdTree};
 use rand::Rng;
 use rayon::prelude::*;
@@ -111,13 +111,19 @@ fn read_data(input_path: &str) -> Result<(Vec<[f64; 2]>, Vec<f64>)> {
     let mut points = Vec::new();
     let mut values = Vec::new();
 
+    let pb = ProgressBar::new_spinner();
+    pb.set_message("reading data");
+    pb.enable_steady_tick(std::time::Duration::from_millis(100));
+
     for line in reader.lines() {
         let line = line?;
         if let Some((p, v)) = parse_point(&line) {
             points.push(p);
             values.push(v);
         }
+        pb.tick();
     }
+    pb.finish_with_message("done reading data");
 
     Ok((points, values))
 }