[windows] Fix event detection right after starting an emitter on PyPy (#796)

And re-add PyPy to CI

Co-authored-by: Mickaël Schoentgen <[email protected]>

Author: oprypin

.github/workflows/tests.yml

@@ -9,9 +9,10 @@ jobs:
     name: Run tests for ${{ matrix.os }} for ${{ matrix.python }}
     runs-on: ${{ matrix.os }}
     strategy:
+      fail-fast: false
       matrix:
         os: [ubuntu-latest, windows-latest, macos-latest]
-        python: [3.6, 3.7, 3.8, 3.9]
+        python: [3.6, 3.7, 3.8, 3.9, pypy3]
     steps:
       - name: Checkout
         uses: actions/checkout@v2

changelog.rst

@@ -8,8 +8,8 @@ Changelog
 
 2021-xx-xx • `full history <https://github.com/gorakhargosh/watchdog/compare/v2.1.2...master>`__
 
--
-- Thanks to our beloved contributors: @
+- [windows] On PyPy, events happening right after ``start()`` were missed. Add a workaround for that. (`#796 <https://github.com/gorakhargosh/watchdog/pull/796>`_)
+- Thanks to our beloved contributors: @oprypin
 
 2.1.1
 ~~~~~

src/watchdog/observers/read_directory_changes.py

@@ -19,6 +19,7 @@
 import threading
 import os.path
 import time
+import platform
 
 from watchdog.events import (
     DirCreatedEvent,
@@ -65,6 +66,12 @@ def __init__(self, event_queue, watch, timeout=DEFAULT_EMITTER_TIMEOUT):
     def on_thread_start(self):
         self._handle = get_directory_handle(self.watch.path)
 
+    if platform.python_implementation() == 'PyPy':
+        def start(self):
+            """PyPy needs some time before receiving events, see #792."""
+            super().start()
+            time.sleep(0.01)
+
     def on_thread_stop(self):
         if self._handle:
             close_directory_handle(self._handle)