mock_instant
mock_instant
This crate allows you to test Instant/Duration code, deterministically per thread.
If cross-thread determinism is required, enable the sync
feature:
mock_instant = { version = "0.3", features = ["sync"] }
It provides a replacement std::time::Instant
and std::time::SystemTime
that uses a deterministic thread-local 'clock'
You can swap out the std::time::Instant
with this one by doing something similar to:
#[cfg(test)]
use mock_instant::Instant;
#[cfg(not(test))]
use std::time::Instant;
or for a std::time::SystemTime
#[cfg(test)]
use mock_instant::{SystemTime, SystemTimeError};
#[cfg(not(test))]
use std::time::{SystemTime, SystemTimeError};
Example
use std::time::Duration;
let now = Instant::now();
MockClock::advance(Duration::from_secs(15));
MockClock::advance(Duration::from_secs(2));
// its been '17' seconds
assert_eq!(now.elapsed(), Duration::from_secs(17));
Mocking a SystemTime
# use mock_instant::{MockClock, SystemTime};
use std::time::Duration;
let now = SystemTime::now();
MockClock::advance_system_time(Duration::from_secs(15));
MockClock::advance_system_time(Duration::from_secs(2));
// its been '17' seconds
assert_eq!(now.elapsed().unwrap(), Duration::from_secs(17));
License: 0BSD