Set the locale based on the config if specified, otherwise the user environment

jrnl/jrnl.py

@@ -1,6 +1,7 @@
 # Copyright (C) 2012-2021 jrnl contributors
 # License: https://www.gnu.org/licenses/gpl-3.0.html
 
+import locale
 import logging
 import sys
 
@@ -48,6 +49,9 @@ def run(args):
         print(f"\n{err}", file=sys.stderr)
         sys.exit(1)
 
+    # From here on, dates and numbers will use the locale supplied by the user
+    _init_locale(config)
+
     # Run post-config command now that config is ready
     if callable(args.postconfig_cmd):
         return args.postconfig_cmd(
@@ -343,3 +347,12 @@ def _display_search_results(args, journal, **kwargs):
         print(exporter.export(journal, args.filename))
     else:
         print(journal.pprint())
+
+
+def _init_locale(config):
+    """
+    Initializes the locale from the environment variables, or the config
+    if specified in the config.
+    """
+    user_locale = config["locale"] if "locale" in config else ""
+    locale.setlocale(locale.LC_ALL, user_locale)

tests/bdd/features/datetime.feature

@@ -172,3 +172,17 @@ Feature: Reading and writing to journal with custom date formats
         Then we should get no error
         And the output should be
             2013-10-27 03:27 Some text.
+
+    Scenario Outline: Dates should be displayed using the specified locale
+        Given we use the config "basic_onefile.yaml"
+        When we run "jrnl --config-override locale <locale> --config-override timeformat \%c -1"
+        Then the output should contain "<expected_date>"
+        
+        Examples: configs
+        | locale | expected_date        |
+        | en_US  | 9/24/2020 9:14:00 AM |
+        | zh_CN  | 2020/9/24 9:14:00    |
+        | ru_RU  | 24.09.2020 9:14:00   |
+        | fr_FR  | 24/09/2020 09:14:00  |
+        | es_ES  | 24/09/2020 9:14:00   |
+        | de_DE  | 24.09.2020 09:14:00  |