Fix incorrect time formatting of locale month (#34)

CHANGELOG.rst

@@ -1,6 +1,7 @@
 Unreleased
 ==========
 
+- Fix incorrect time formatting of locale month using ``MMM`` and ``MMMM`` tokens (`#34 <https://github.com/Delgan/loguru/pull/34>`_, thanks `@nasyxx <https://github.com/nasyxx>`_)
 - Fix race condition permitting to write on a stopped handler
 
 

loguru/_datetime.py

@@ -29,8 +29,8 @@ def __format__(self, spec):
             "YYYY": "%04d" % year,
             "YY": "%02d" % (year % 100),
             "Q": "%d" % ((month - 1) // 3 + 1),
-            "MMMM": month_name[month - 1],
-            "MMM": month_abbr[month - 1],
+            "MMMM": month_name[month],
+            "MMM": month_abbr[month],
             "MM": "%02d" % month,
             "M": "%d" % month,
             "DDDD": "%03d" % yearday,

tests/test_datetime.py

@@ -1,4 +1,5 @@
 import pytest
+import datetime
 from loguru import logger
 import sys
 
@@ -38,6 +39,14 @@ def test_formatting(writer, monkeypatch_date, time_format, date, expected):
     assert result == expected + "\n"
 
 
+def test_locale_formatting(writer, monkeypatch_date):
+    date = (2011, 1, 1, 22, 22, 22, 0)
+    monkeypatch_date(*date)
+    logger.add(writer, format="{time:MMMM MMM dddd ddd}")
+    logger.debug("Test")
+    assert writer.read() == datetime.datetime(*date).strftime("%B %b %A %a\n")
+
+
 def test_stdout_formatting(monkeypatch_date, capsys):
     monkeypatch_date(2015, 12, 25, 19, 13, 18, 0, "A", 5400)
     logger.add(sys.stdout, format="{time:YYYY [MM] DD HHmmss Z} {message}")