Struct SimClock 

pub struct SimClock { /* private fields */ }

A simulated clock for deterministic testing.

TigerStyle:

• Time only moves forward
• All time operations are explicit
• No reliance on system time
• Supports async sleep with notify for coordination

Thread-safe via Arc for current time.

Implementations

impl SimClock

pub fn new() -> Self

Create a new clock starting at time zero.

Example

use umi_memory::dst::SimClock;
let clock = SimClock::new();
assert_eq!(clock.now_ms(), 0);

pub fn at_ms(start_ms: u64) -> Self

Create a clock starting at the given millisecond timestamp.

pub fn at_datetime(dt: DateTime<Utc>) -> Self

Create a clock starting at the given DateTime.

pub fn from_epoch() -> Self

Create a clock starting at Unix epoch (1970-01-01).

pub fn now_ms(&self) -> u64

Get current time in milliseconds.

pub fn now_secs(&self) -> u64

Get current time in seconds (truncated).

pub fn now(&self) -> DateTime<Utc>

Get current time as DateTime.

pub fn advance_ms(&self, ms: u64) -> u64

Advance time by the given milliseconds.

Panics

Panics if ms exceeds DST_TIME_ADVANCE_MS_MAX.

Returns

The new current time.

pub fn advance_secs(&self, secs: f64) -> u64

Advance time by the given seconds.

Panics

Panics if resulting ms exceeds DST_TIME_ADVANCE_MS_MAX.

pub fn advance(&self, duration: Duration)

Advance time by a chrono Duration.

pub fn set_ms(&self, ms: u64)

Set time to absolute value.

Panics

Panics if new time is less than current time.

pub fn set(&self, time: DateTime<Utc>)

Set time to a DateTime.

pub fn elapsed_since(&self, since: u64) -> u64

Get elapsed time since a given timestamp.

Panics

Panics if since is in the future.

pub fn has_elapsed(&self, since: u64, duration_ms: u64) -> bool

Check if a given duration has elapsed since a timestamp.

pub fn is_past_ms(&self, deadline_ms: u64) -> bool

Check if a deadline (in ms) has passed.

pub fn is_past(&self, deadline: DateTime<Utc>) -> bool

Check if a DateTime deadline has passed.

pub fn timestamp(&self) -> u64

Get a timestamp that represents “now” for storing.

pub async fn sleep_ms(&self, duration_ms: u64)

Sleep until the specified duration has passed.

In simulation mode, this yields and waits for time to be advanced. Returns when current_time >= start_time + duration_ms.

pub async fn sleep(&self, duration: Duration)

Sleep for a chrono Duration.

pub async fn sleep_until_ms(&self, deadline_ms: u64)

Sleep until a specific deadline.

Trait Implementations

impl Clone for SimClock

fn clone(&self) -> SimClock

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for SimClock

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Default for SimClock

fn default() -> Self

Returns the “default value” for a type.