Struct MockClock 

pub struct MockClock { /* private fields */ }

Clock implementation whose readings are derived from a shared mock timeline.

MockClock is a controllable UTC clock for tests. It combines a monotonic MockTimeline with a wall-clock anchor. The current UTC reading is:

wall_origin + timeline.elapsed()

Creating a clock with at or with_timeline establishes the wall-clock value for the timeline’s current elapsed instant. Later calls to set_time move only that wall-clock anchor; they do not change elapsed mock time. Calls to advance or add_duration advance the underlying monotonic timeline and therefore wake timeline waiters such as mock sleeps.

This clock implements Clock, NanoClock, and ControllableClock. It is frozen until its timeline advances, which makes elapsed-time tests deterministic and independent of wall-clock scheduling noise.

A cloned MockClock shares both the timeline and the wall-clock anchor with the original clock. A clock created with MockClock::with_timeline shares only the provided timeline; it owns its own wall-clock anchor.

Implementations

impl MockClock

pub fn new() -> Self

Creates a mock clock anchored at the current system time.

Returns

A mock clock with a fresh zero-elapsed timeline.

pub fn at(start: DateTime<Utc>) -> Self

Creates a mock clock anchored at a specific UTC time.

Parameters

• start: UTC time returned while the associated timeline is at its current elapsed value.

Returns

A mock clock with a fresh timeline.

pub fn with_timeline(start: DateTime<Utc>, timeline: MockTimeline) -> Self

Creates a mock clock backed by an existing timeline.

Parameters

• start: UTC time returned for the timeline’s current elapsed value.
• timeline: Shared mock timeline used by this clock.

Returns

A mock clock view over the provided timeline.

pub fn timeline(&self) -> MockTimeline

Returns the timeline backing this clock.

Returns

The shared mock timeline.

pub fn advance(&self, duration: StdDuration)

Advances the shared mock timeline.

Parameters

• duration: Duration to add to the shared timeline.

pub fn try_reset(&self) -> Result<(), MockTimeError>

Resets the shared timeline and this clock’s wall-time anchor.

Returns

Ok(()) when reset succeeds.

Errors

Returns MockTimeError::ActiveWaiters when timeline waiters are active.

Trait Implementations

impl Clock for MockClock

fn millis(&self) -> i64

Returns the current mock UTC timestamp in milliseconds.

fn time(&self) -> DateTime<Utc>

Returns the current mock UTC time with nanosecond precision.

impl Clone for MockClock

fn clone(&self) -> MockClock

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl ControllableClock for MockClock

fn set_time(&self, instant: DateTime<Utc>)

Reanchors this clock so the current timeline instant reads as instant.

fn add_duration(&self, duration: Duration)

Advances the shared mock timeline by a non-negative duration.

Panics

Panics if duration is negative or cannot be represented as std::time::Duration.

fn reset(&self)

Resets the shared timeline and this clock’s wall-time anchor.

Panics

Panics when active timeline waiters prevent reset.

impl Debug for MockClock

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

Formats the value using the given formatter.

impl Default for MockClock

fn default() -> Self

Creates a mock clock anchored at the current system time.

impl NanoClock for MockClock

fn nanos(&self) -> i128

Returns the current mock UTC timestamp in nanoseconds.

fn time_precise(&self) -> DateTime<Utc>

Returns the current time as a DateTime<Utc> with nanosecond precision.