Large redesign

Use the whole width of the terminal assume width of 80 if none found

Show percentages in the final column. Show ASCII bars indicating usage
of the underlying directories in the space inbetween.

Display (height of terminal - 10) entries by default.

Reverse the output order so largest is at the bottom.

Break up tests. Change older tests to check real output of program.

src/main.rs

@@ -1,16 +1,19 @@
 #[macro_use]
 extern crate clap;
+extern crate unicode_width;
 
 use self::display::draw_it;
 use crate::utils::is_a_parent_of;
 use clap::{App, AppSettings, Arg};
+use std::cmp::max;
 use std::path::PathBuf;
+use terminal_size::{terminal_size, Height, Width};
 use utils::{find_big_ones, get_dir_tree, simplify_dir_names, sort, trim_deep_ones, Node};
 
 mod display;
 mod utils;
 
-static DEFAULT_NUMBER_OF_LINES: usize = 20;
+static DEFAULT_NUMBER_OF_LINES: usize = 30;
 
 #[cfg(windows)]
 fn init_color() {
@@ -20,9 +23,21 @@ fn init_color() {
 #[cfg(not(windows))]
 fn init_color() {}
 
+fn get_height_of_terminal() -> usize {
+    // Windows CI runners detect a terminal height of 0
+    if let Some((Width(_w), Height(h))) = terminal_size() {
+        max(h as usize, DEFAULT_NUMBER_OF_LINES) - 10
+    } else {
+        DEFAULT_NUMBER_OF_LINES - 10
+    }
+}
+
 fn main() {
     init_color();
-    let def_num_str = DEFAULT_NUMBER_OF_LINES.to_string();
+
+    let default_height = get_height_of_terminal();
+    let def_num_str = default_height.to_string();
+
     let options = App::new("Dust")
         .about("Like du but more intuitive")
         .version(crate_version!())
@@ -80,7 +95,7 @@ fn main() {
             Arg::with_name("reverse")
                 .short("r")
                 .long("reverse")
-                .help("If applied tree will be printed upside down (biggest lowest)"),
+                .help("If applied tree will be printed upside down (biggest highest)"),
         )
         .arg(
             Arg::with_name("no_colors")
@@ -88,6 +103,12 @@ fn main() {
                 .long("no_colors")
                 .help("If applied no colors will be printed (normally largest directories are marked in red"),
         )
+        .arg(
+            Arg::with_name("no_bars")
+                .short("b")
+                .long("no_percent_bars")
+                .help("If applied no percent bars or percents will be displayed"),
+        )
         .arg(Arg::with_name("inputs").multiple(true))
         .get_matches();
 
@@ -102,7 +123,7 @@ fn main() {
         Ok(v) => v,
         Err(_) => {
             eprintln!("Ignoring bad value for number_of_lines");
-            DEFAULT_NUMBER_OF_LINES
+            default_height
         }
     };
 
@@ -131,7 +152,7 @@ fn main() {
             .map_err(|_| eprintln!("Ignoring bad value for depth"))
             .ok()
     });
-    if options.is_present("depth") && number_of_lines != DEFAULT_NUMBER_OF_LINES {
+    if options.is_present("depth") && number_of_lines != default_height {
         eprintln!("Use either -n or -d. Not both");
         return;
     }
@@ -163,8 +184,9 @@ fn main() {
     draw_it(
         permissions,
         options.is_present("display_full_paths"),
-        options.is_present("reverse"),
+        !options.is_present("reverse"),
         options.is_present("no_colors"),
+        options.is_present("no_bars"),
         tree,
     );
 }
@@ -200,6 +222,3 @@ fn recursively_build_tree(parent_node: &mut Node, new_node: Node, depth: Option<
         parent_node.children.push(new_node);
     }
 }
-
-#[cfg(test)]
-mod tests;