Files
nushell/crates/nu-cli/src/app/stopwatch.rs
Darren Schroeder 23ba01d89c add performance metrics for measuring startup time (#3854)
* add performance metrics for measureing startup time

* removed some comments

* update so tests pass

* update default.toml for tests, merged main

* fix clippy lints

* wording changes
2021-07-29 18:52:40 -05:00

119 lines
3.3 KiB
Rust

#![allow(dead_code)]
use std::default::Default;
use std::fmt;
use std::time::{Duration, Instant};
#[derive(Clone, Copy)]
pub struct Stopwatch {
/// The time the stopwatch was started last, if ever.
start_time: Option<Instant>,
/// The time the stopwatch was split last, if ever.
split_time: Option<Instant>,
/// The time elapsed while the stopwatch was running (between start() and stop()).
elapsed: Duration,
}
impl Default for Stopwatch {
fn default() -> Stopwatch {
Stopwatch {
start_time: None,
split_time: None,
elapsed: Duration::from_secs(0),
}
}
}
impl fmt::Display for Stopwatch {
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
return write!(f, "{}ms", self.elapsed_ms());
}
}
impl Stopwatch {
/// Returns a new stopwatch.
pub fn new() -> Stopwatch {
let sw: Stopwatch = Default::default();
sw
}
/// Returns a new stopwatch which will immediately be started.
pub fn start_new() -> Stopwatch {
let mut sw = Stopwatch::new();
sw.start();
sw
}
/// Starts the stopwatch.
pub fn start(&mut self) {
self.start_time = Some(Instant::now());
}
/// Stops the stopwatch.
pub fn stop(&mut self) {
self.elapsed = self.elapsed();
self.start_time = None;
self.split_time = None;
}
/// Resets all counters and stops the stopwatch.
pub fn reset(&mut self) {
self.elapsed = Duration::from_secs(0);
self.start_time = None;
self.split_time = None;
}
/// Resets and starts the stopwatch again.
pub fn restart(&mut self) {
self.reset();
self.start();
}
/// Returns whether the stopwatch is running.
pub fn is_running(&self) -> bool {
self.start_time.is_some()
}
/// Returns the elapsed time since the start of the stopwatch.
pub fn elapsed(&self) -> Duration {
match self.start_time {
// stopwatch is running
Some(t1) => t1.elapsed() + self.elapsed,
// stopwatch is not running
None => self.elapsed,
}
}
/// Returns the elapsed time since the start of the stopwatch in milliseconds.
pub fn elapsed_ms(&self) -> i64 {
let dur = self.elapsed();
(dur.as_secs() * 1000 + dur.subsec_millis() as u64) as i64
}
/// Returns the elapsed time since last split or start/restart.
///
/// If the stopwatch is in stopped state this will always return a zero Duration.
pub fn elapsed_split(&mut self) -> Duration {
match self.start_time {
// stopwatch is running
Some(start) => {
let res = match self.split_time {
Some(split) => split.elapsed(),
None => start.elapsed(),
};
self.split_time = Some(Instant::now());
res
}
// stopwatch is not running
None => Duration::from_secs(0),
}
}
/// Returns the elapsed time since last split or start/restart in milliseconds.
///
/// If the stopwatch is in stopped state this will always return zero.
pub fn elapsed_split_ms(&mut self) -> i64 {
let dur = self.elapsed_split();
(dur.as_secs() * 1000 + dur.subsec_millis() as u64) as i64
}
}