原生 Clock

原生 API 目录 · 手册目录

方法与属性索引

• fast_forward
• install
• on
• once
• pause_at
• remove_listener
• resume
• run_for
• set_fixed_time
• set_system_time

fast_forward

同步

def fast_forward(self, ticks: Union[int, str]) -> None

Clock.fast_forward

Advance the clock by jumping forward in time. Only fires due timers at most once. This is equivalent to user closing the laptop lid for a while and reopening it later, after given time.

Usage

page.clock.fast_forward(1000)
page.clock.fast_forward("30:00")

Parameters

异步

async def fast_forward(self, ticks: Union[int, str]) -> None

Clock.fast_forward

Advance the clock by jumping forward in time. Only fires due timers at most once. This is equivalent to user closing the laptop lid for a while and reopening it later, after given time.

Usage

await page.clock.fast_forward(1000)
await page.clock.fast_forward("30:00")

Parameters

install

同步

def install(self, *, time: Union[float, str, datetime.datetime, NoneType] = None) -> None

Clock.install

Install fake implementations for the following time-related functions:

• Date
• Temporal.Now
• setTimeout
• clearTimeout
• setInterval
• clearInterval
• requestAnimationFrame
• cancelAnimationFrame
• requestIdleCallback
• cancelIdleCallback
• performance

Fake timers are used to manually control the flow of time in tests. They allow you to advance time, fire timers, and control the behavior of time-dependent functions. See clock.run_for() and clock.fast_forward() for more information.

Parameters

异步

async def install(self, *, time: Union[float, str, datetime.datetime, NoneType] = None) -> None

Clock.install

Install fake implementations for the following time-related functions:

• Date
• Temporal.Now
• setTimeout
• clearTimeout
• setInterval
• clearInterval
• requestAnimationFrame
• cancelAnimationFrame
• requestIdleCallback
• cancelIdleCallback
• performance

Fake timers are used to manually control the flow of time in tests. They allow you to advance time, fire timers, and control the behavior of time-dependent functions. See clock.run_for() and clock.fast_forward() for more information.

Parameters

on

同步

def on(self, event: Any, f: Any) -> None

Registers the function f to the event name event.

异步

def on(self, event: Any, f: Any) -> None

Registers the function f to the event name event.

once

同步

def once(self, event: Any, f: Any) -> None

The same as self.on, except that the listener is automatically removed after being called.

异步

def once(self, event: Any, f: Any) -> None

The same as self.on, except that the listener is automatically removed after being called.

pause_at

同步

def pause_at(self, time: Union[float, str, datetime.datetime]) -> None

Clock.pause_at

Advance the clock by jumping forward in time and pause the time. Once this method is called, no timers are fired unless clock.run_for(), clock.fast_forward(), clock.pause_at() or clock.resume() is called.

Only fires due timers at most once. This is equivalent to user closing the laptop lid for a while and reopening it at the specified time and pausing.

Usage

page.clock.pause_at(datetime.datetime(2020, 2, 2))
page.clock.pause_at("2020-02-02")

For best results, install the clock before navigating the page and set it to a time slightly before the intended test time. This ensures that all timers run normally during page loading, preventing the page from getting stuck. Once the page has fully loaded, you can safely use clock.pause_at() to pause the clock.

# Initialize clock with some time before the test time and let the page load
# naturally. `Date.now` will progress as the timers fire.
page.clock.install(time=datetime.datetime(2024, 12, 10, 8, 0, 0))
page.goto("http://localhost:3333")
page.clock.pause_at(datetime.datetime(2024, 12, 10, 10, 0, 0))

Parameters

异步

async def pause_at(self, time: Union[float, str, datetime.datetime]) -> None

Clock.pause_at

Advance the clock by jumping forward in time and pause the time. Once this method is called, no timers are fired unless clock.run_for(), clock.fast_forward(), clock.pause_at() or clock.resume() is called.

Only fires due timers at most once. This is equivalent to user closing the laptop lid for a while and reopening it at the specified time and pausing.

Usage

await page.clock.pause_at(datetime.datetime(2020, 2, 2))
await page.clock.pause_at("2020-02-02")

For best results, install the clock before navigating the page and set it to a time slightly before the intended test time. This ensures that all timers run normally during page loading, preventing the page from getting stuck. Once the page has fully loaded, you can safely use clock.pause_at() to pause the clock.

# Initialize clock with some time before the test time and let the page load
# naturally. `Date.now` will progress as the timers fire.
await page.clock.install(time=datetime.datetime(2024, 12, 10, 8, 0, 0))
await page.goto("http://localhost:3333")
await page.clock.pause_at(datetime.datetime(2024, 12, 10, 10, 0, 0))

Parameters

remove_listener

同步

def remove_listener(self, event: Any, f: Any) -> None

Removes the function f from event.

异步

def remove_listener(self, event: Any, f: Any) -> None

Removes the function f from event.

resume

同步

def resume(self) -> None

Clock.resume

Resumes timers. Once this method is called, time resumes flowing, timers are fired as usual.

异步

async def resume(self) -> None

Clock.resume

Resumes timers. Once this method is called, time resumes flowing, timers are fired as usual.

run_for

同步

def run_for(self, ticks: Union[int, str]) -> None

Clock.run_for

Advance the clock, firing all the time-related callbacks.

Usage

page.clock.run_for(1000);
page.clock.run_for("30:00")

Parameters

异步

async def run_for(self, ticks: Union[int, str]) -> None

Clock.run_for

Advance the clock, firing all the time-related callbacks.

Usage

await page.clock.run_for(1000);
await page.clock.run_for("30:00")

Parameters

set_fixed_time

同步

def set_fixed_time(self, time: Union[float, str, datetime.datetime]) -> None

Clock.set_fixed_time

Makes Date.now and new Date() return fixed fake time at all times, keeps all the timers running.

Use this method for simple scenarios where you only need to test with a predefined time. For more advanced scenarios, use clock.install() instead. Read docs on clock emulation to learn more.

Usage

page.clock.set_fixed_time(datetime.datetime.now())
page.clock.set_fixed_time(datetime.datetime(2020, 2, 2))
page.clock.set_fixed_time("2020-02-02")

Parameters

异步

async def set_fixed_time(self, time: Union[float, str, datetime.datetime]) -> None

Clock.set_fixed_time

Makes Date.now and new Date() return fixed fake time at all times, keeps all the timers running.

Use this method for simple scenarios where you only need to test with a predefined time. For more advanced scenarios, use clock.install() instead. Read docs on clock emulation to learn more.

Usage

await page.clock.set_fixed_time(datetime.datetime.now())
await page.clock.set_fixed_time(datetime.datetime(2020, 2, 2))
await page.clock.set_fixed_time("2020-02-02")

Parameters

set_system_time

同步

def set_system_time(self, time: Union[float, str, datetime.datetime]) -> None

Clock.set_system_time

Sets system time, but does not trigger any timers. Use this to test how the web page reacts to a time shift, for example switching from summer to winter time, or changing time zones.

Usage

page.clock.set_system_time(datetime.datetime.now())
page.clock.set_system_time(datetime.datetime(2020, 2, 2))
page.clock.set_system_time("2020-02-02")

Parameters

异步

async def set_system_time(self, time: Union[float, str, datetime.datetime]) -> None

Clock.set_system_time

Sets system time, but does not trigger any timers. Use this to test how the web page reacts to a time shift, for example switching from summer to winter time, or changing time zones.

Usage

await page.clock.set_system_time(datetime.datetime.now())
await page.clock.set_system_time(datetime.datetime(2020, 2, 2))
await page.clock.set_system_time("2020-02-02")

Parameters