In the logtesting support module, fix the setting of logging level.

third_party/WebKit/Tools/Scripts/webkitpy/common/system/logtesting_unittest.py

Index: third_party/WebKit/Tools/Scripts/webkitpy/common/system/logtesting_unittest.py
diff --git a/third_party/WebKit/Tools/Scripts/webkitpy/common/system/logtesting_unittest.py b/third_party/WebKit/Tools/Scripts/webkitpy/common/system/logtesting_unittest.py
new file mode 100644
index 0000000000000000000000000000000000000000..61c30c33aa529f9a0941e72415ce692065e764bc
--- /dev/null
+++ b/third_party/WebKit/Tools/Scripts/webkitpy/common/system/logtesting_unittest.py
@@ -0,0 +1,60 @@
+# Copyright 2016 The Chromium Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+import logging
+import unittest
+
+from webkitpy.common.system.logtesting import LoggingTestCase, LogTesting, TestLogStream
+
+
+class TestLogStreamTest(unittest.TestCase):
+
+    def test_passed_to_stream_handler(self):
+        stream = TestLogStream(self)
+        handler = logging.StreamHandler(stream)
+        logger = logging.getLogger('test.logger')
+        logger.addHandler(handler)
+        logger.setLevel(logging.INFO)
+        logger.info('bar')
+        stream.assertMessages(['bar\n'])
+
+    def test_direct_use(self):
+        stream = TestLogStream(self)
+        stream.write('foo')
+        stream.flush()
+        stream.assertMessages(['foo'])
+
+
+class LogTestingTest(unittest.TestCase):
+
+    def test_basic(self):
+        log_testing_instance = LogTesting.setUp(self)
+        logger = logging.getLogger('test.logger')
+        logger.info('my message')
+        log_testing_instance.assertMessages(['INFO: my message\n'])
+        # The list of messages is cleared after being checked once.
+        log_testing_instance.assertMessages([])
+
+    def test_log_level_warning(self):
+        log_testing_instance = LogTesting.setUp(self, logging_level=logging.WARNING)
+        logger = logging.getLogger('test.logger')
+        logger.info('my message')
+        log_testing_instance.assertMessages([])
+
+
+class LoggingTestCaseTest(LoggingTestCase):
+
+    def test_basic(self):
+        self.example_logging_code()
+        self.assertLog([
+            'INFO: Informative message\n',
+            'WARNING: Warning message\n',
+        ])
+
+    @staticmethod
+    def example_logging_code():
+        logger = logging.getLogger('test.logger')
+        logger.debug('Debugging message')
+        logger.info('Informative message')
+        logger.warning('Warning message')