setup_logging: warn about invalid log level from env (#413)

Author: blueyed

pynvim/__init__.py

@@ -135,12 +135,14 @@ def setup_logging(name):
             '%(filename)s:%(funcName)s:%(lineno)s] %(process)s - %(message)s')
         logging.root.addHandler(handler)
         level = logging.INFO
-        if 'NVIM_PYTHON_LOG_LEVEL' in os.environ:
-            lvl = getattr(logging,
-                          os.environ['NVIM_PYTHON_LOG_LEVEL'].strip(),
-                          level)
+        env_log_level = os.environ.get('NVIM_PYTHON_LOG_LEVEL', None)
+        if env_log_level is not None:
+            lvl = getattr(logging, env_log_level.strip(), None)
             if isinstance(lvl, int):
                 level = lvl
+            else:
+                logger.warning('Invalid NVIM_PYTHON_LOG_LEVEL: %r, using INFO.',
+                               env_log_level)
         logger.setLevel(level)
 
 

test/test_logging.py

@@ -0,0 +1,36 @@
+import os
+import sys
+
+
+def test_setup_logging(monkeypatch, tmpdir, caplog):
+    from pynvim import setup_logging
+
+    major_version = sys.version_info[0]
+
+    setup_logging('name1')
+    assert caplog.messages == []
+
+    def get_expected_logfile(prefix, name):
+        return '{}_py{}_{}'.format(prefix, major_version, name)
+
+    prefix = tmpdir.join('testlog1')
+    monkeypatch.setenv('NVIM_PYTHON_LOG_FILE', str(prefix))
+    setup_logging('name2')
+    assert caplog.messages == []
+    logfile = get_expected_logfile(prefix, 'name2')
+    assert os.path.exists(logfile)
+    assert open(logfile, 'r').read() == ''
+
+    monkeypatch.setenv('NVIM_PYTHON_LOG_LEVEL', 'invalid')
+    setup_logging('name3')
+    assert caplog.record_tuples == [
+        ('pynvim', 30, "Invalid NVIM_PYTHON_LOG_LEVEL: 'invalid', using INFO."),
+    ]
+    logfile = get_expected_logfile(prefix, 'name2')
+    assert os.path.exists(logfile)
+    with open(logfile, 'r') as f:
+        lines = f.readlines()
+        assert len(lines) == 1
+        assert lines[0].endswith(
+            "- Invalid NVIM_PYTHON_LOG_LEVEL: 'invalid', using INFO.\n"
+        )