test: add unit tests for setup_logger function

.github/workflows/publish.yml

@@ -11,6 +11,10 @@ permissions:
 
 jobs:
   release:
+    # Releases are cut from the upstream repository only. Without this guard the
+    # workflow also runs on forks, where semantic-release rewrites the version in
+    # pyproject.toml, commits to the default branch and attempts a PyPI upload.
+    if: github.repository == 'appium/python-client'
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v7

test/unit/common/logger_test.py

@@ -0,0 +1,61 @@
+#!/usr/bin/env python
+
+# 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
+#
+#     http://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 logging
+import sys
+from collections.abc import Iterator
+
+import pytest
+
+from appium.common.logger import logger, setup_logger
+
+
+@pytest.fixture(autouse=True)
+def restore_logger() -> Iterator[None]:
+    # setup_logger mutates the shared module logger, so put it back after each test.
+    handlers = list(logger.handlers)
+    level = logger.level
+    propagate = logger.propagate
+    yield
+    logger.handlers[:] = handlers
+    logger.setLevel(level)
+    logger.propagate = propagate
+
+
+def test_setup_logger_default() -> None:
+    handlers_before = list(logger.handlers)
+
+    setup_logger()
+
+    assert logger.propagate is False
+    assert logger.level == logging.NOTSET
+    assert len(logger.handlers) == len(handlers_before) + 1
+
+    new_handler = logger.handlers[-1]
+    assert isinstance(new_handler, logging.StreamHandler)
+    assert new_handler.stream == sys.stderr
+
+
+def test_setup_logger_custom_level() -> None:
+    handlers_before = list(logger.handlers)
+
+    setup_logger(level=logging.DEBUG)
+
+    assert logger.propagate is False
+    assert logger.level == logging.DEBUG
+    assert len(logger.handlers) == len(handlers_before) + 1
+
+    new_handler = logger.handlers[-1]
+    assert isinstance(new_handler, logging.StreamHandler)
+    assert new_handler.stream == sys.stderr