Pyee watcher context

tests/utils_test.py

@@ -0,0 +1,77 @@
+# Copyright 2021-2023 Google LLC
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      https://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+import contextlib
+import logging
+import os
+
+from bumble import utils
+from pyee import EventEmitter
+from unittest.mock import MagicMock
+
+
+def test_on():
+    emitter = EventEmitter()
+    with contextlib.closing(utils.EventWatcher()) as context:
+        mock = MagicMock()
+        context.on(emitter, 'event', mock)
+
+        emitter.emit('event')
+
+    assert not emitter.listeners('event')
+    assert mock.call_count == 1
+
+
+def test_on_decorator():
+    emitter = EventEmitter()
+    with contextlib.closing(utils.EventWatcher()) as context:
+        mock = MagicMock()
+
+        @context.on(emitter, 'event')
+        def on_event(*_):
+            mock()
+
+        emitter.emit('event')
+
+    assert not emitter.listeners('event')
+    assert mock.call_count == 1
+
+
+def test_multiple_handlers():
+    emitter = EventEmitter()
+    with contextlib.closing(utils.EventWatcher()) as context:
+        mock = MagicMock()
+
+        context.once(emitter, 'a', mock)
+        context.once(emitter, 'b', mock)
+
+        emitter.emit('b', 'b')
+
+    assert not emitter.listeners('a')
+    assert not emitter.listeners('b')
+
+    mock.assert_called_once_with('b')
+
+
+# -----------------------------------------------------------------------------
+def run_tests():
+    test_on()
+    test_on_decorator()
+    test_multiple_handlers()
+
+
+# -----------------------------------------------------------------------------
+if __name__ == '__main__':
+    logging.basicConfig(level=os.environ.get('BUMBLE_LOGLEVEL', 'INFO').upper())
+    run_tests()