70 lines
1.9 KiB
Python
70 lines
1.9 KiB
Python
import functools
|
|
import time
|
|
from dataclasses import dataclass, field
|
|
from typing import Callable, ClassVar, Dict, Optional
|
|
|
|
|
|
class TimerError(Exception):
|
|
"""A custom exception used to report errors in use of Timer class."""
|
|
|
|
pass
|
|
|
|
|
|
@dataclass
|
|
class Timer:
|
|
"""Time a section of code."""
|
|
|
|
timers: ClassVar[Dict[str, float]] = {}
|
|
name: Optional[str] = None
|
|
text: str = "Elapsed time: {:0.4f} seconds"
|
|
logger: Optional[Callable[[str], None]] = print
|
|
_start_time: Optional[float] = field(default=None, init=False, repr=False)
|
|
|
|
def __post_init__(self) -> None:
|
|
"""Add timer to dict of timers after initialization."""
|
|
if self.name is not None:
|
|
self.timers.setdefault(self.name, 0)
|
|
|
|
def __enter__(self):
|
|
"""Start a new timer as a context manager."""
|
|
self.start()
|
|
return self
|
|
|
|
def __exit__(self, *exc_info):
|
|
"""Stop the context manager timer."""
|
|
self.stop()
|
|
|
|
def __call__(self, func):
|
|
"""Support using Timer as a decorator."""
|
|
|
|
@functools.wraps(func)
|
|
def wrapper_timer(*args, **kwargs):
|
|
with self:
|
|
return func(*args, **kwargs)
|
|
|
|
return wrapper_timer
|
|
|
|
def start(self) -> None:
|
|
"""Start a new timer."""
|
|
if self._start_time is not None:
|
|
raise TimerError("Timer is running. Use .stop() to stop it")
|
|
|
|
self._start_time = time.perf_counter()
|
|
|
|
def stop(self) -> float:
|
|
"""Stop the timer, and report the elapsed time."""
|
|
if self._start_time is None:
|
|
raise TimerError("Timer is not running. Use .start() to start it")
|
|
|
|
# Calculate elapsed time
|
|
elapsed_time = time.perf_counter() - self._start_time
|
|
self._start_time = None
|
|
|
|
# Report elapsed time
|
|
if self.logger:
|
|
self.logger(self.text.format(elapsed_time))
|
|
if self.name:
|
|
self.timers[self.name] += elapsed_time
|
|
|
|
return elapsed_time
|