rust/crates/ra_cli/src/progress_report.rs

121 lines
3.2 KiB
Rust

//! A simple progress bar
//!
//! A single thread non-optimized progress bar
use std::io::Write;
/// A Simple ASCII Progress Bar
pub struct ProgressReport {
curr: f32,
text: String,
hidden: bool,
len: u64,
pos: u64,
msg: String,
}
impl ProgressReport {
pub fn new(len: u64) -> ProgressReport {
ProgressReport {
curr: 0.0,
text: String::new(),
hidden: false,
len,
pos: 0,
msg: String::new(),
}
}
pub fn hidden() -> ProgressReport {
ProgressReport {
curr: 0.0,
text: String::new(),
hidden: true,
len: 0,
pos: 0,
msg: String::new(),
}
}
pub fn set_message(&mut self, msg: &str) {
self.msg = msg.to_string();
self.tick();
}
pub fn println<I: Into<String>>(&mut self, msg: I) {
self.clear();
println!("{}", msg.into());
self.tick();
}
pub fn inc(&mut self, delta: u64) {
self.pos += delta;
if self.len == 0 {
self.set_value(0.0)
} else {
self.set_value((self.pos as f32) / (self.len as f32))
}
self.tick();
}
pub fn finish_and_clear(&mut self) {
self.clear();
}
pub fn tick(&mut self) {
if self.hidden {
return;
}
let percent = (self.curr * 100.0) as u32;
let text = format!("{}/{} {:3>}% {}", self.pos, self.len, percent, self.msg);
self.update_text(&text);
}
fn update_text(&mut self, text: &str) {
// Get length of common portion
let mut common_prefix_length = 0;
let common_length = usize::min(self.text.len(), text.len());
while common_prefix_length < common_length
&& text.chars().nth(common_prefix_length).unwrap()
== self.text.chars().nth(common_prefix_length).unwrap()
{
common_prefix_length += 1;
}
// Backtrack to the first differing character
let mut output = String::new();
output += &'\x08'.to_string().repeat(self.text.len() - common_prefix_length);
// Output new suffix
output += &text[common_prefix_length..text.len()];
// If the new text is shorter than the old one: delete overlapping characters
if let Some(overlap_count) = self.text.len().checked_sub(text.len()) {
if overlap_count > 0 {
output += &" ".repeat(overlap_count);
output += &"\x08".repeat(overlap_count);
}
}
let _ = std::io::stdout().write(output.as_bytes());
let _ = std::io::stdout().flush();
self.text = text.to_string();
}
fn set_value(&mut self, value: f32) {
self.curr = f32::max(0.0, f32::min(1.0, value));
}
fn clear(&mut self) {
if self.hidden {
return;
}
// Fill all last text to space and return the cursor
let spaces = " ".repeat(self.text.len());
let backspaces = "\x08".repeat(self.text.len());
print!("{}{}{}", backspaces, spaces, backspaces);
self.text = String::new();
}
}