Skip to content

Instantly share code, notes, and snippets.

@sosukeinu
Forked from walkermatt/debounce.py
Created July 19, 2018 15:37
Show Gist options
  • Save sosukeinu/964687c6b00c24e72b59db5ad05f128f to your computer and use it in GitHub Desktop.
Save sosukeinu/964687c6b00c24e72b59db5ad05f128f to your computer and use it in GitHub Desktop.
A debounce function decorator in Python similar to the one in underscore.js, tested with 2.7
from threading import Timer
def debounce(wait):
""" Decorator that will postpone a functions
execution until after wait seconds
have elapsed since the last time it was invoked. """
def decorator(fn):
def debounced(*args, **kwargs):
def call_it():
fn(*args, **kwargs)
try:
debounced.t.cancel()
except(AttributeError):
pass
debounced.t = Timer(wait, call_it)
debounced.t.start()
return debounced
return decorator
import unittest
import time
from debounce import debounce
class TestDebounce(unittest.TestCase):
@debounce(10)
def increment(self):
""" Simple function that
increments a counter when
called, used to test the
debounce function decorator """
self.count += 1
def setUp(self):
self.count = 0
def test_debounce(self):
""" Test that the increment
function is being debounced.
The counter should only be incremented
once 10 seconds after the last call
to the function """
self.assertTrue(self.count == 0)
self.increment()
self.increment()
time.sleep(9)
self.assertTrue(self.count == 0)
self.increment()
self.increment()
self.increment()
self.increment()
self.assertTrue(self.count == 0)
time.sleep(10)
self.assertTrue(self.count == 1)
if __name__ == '__main__':
unittest.main()
Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment