Make WuttaConfig.get_list() return None by default

instead of empty list `[]`

CHANGELOG.md

@@ -5,6 +5,11 @@ All notable changes to WuttJamaican will be documented in this file.
 The format is based on [Keep a Changelog](http://keepachangelog.com/en/1.0.0/)
 and this project adheres to [Semantic Versioning](http://semver.org/spec/v2.0.0.html).
 
+## Unreleased
+### Changed
+- `WuttaConfig.get_list()` now returns `None` (instead of `[]`) by
+  default if there is no config value present.
+
 ## [0.1.9] - 2023-11-30
 ### Changed
 - Add generic handler base class, tests, docs.

src/wuttjamaican/conf.py

@@ -2,7 +2,7 @@
 ################################################################################
 #
 #  WuttJamaican -- Base package for Wutta Framework
-#  Copyright © 2023 Lance Edgar
+#  Copyright © 2023-2024 Lance Edgar
 #
 #  This file is part of Wutta Framework.
 #
@@ -480,9 +480,13 @@ class WuttaConfig:
         Accepts same params as :meth:`get()` but if a value is found,
         it will be coerced to list via
         :func:`~wuttjamaican.util.parse_list()`.
+
+        :returns: If a value is found, a list is returned.  If no
+           value, returns ``None``.
         """
         value = self.get(*args, **kwargs)
-        return parse_list(value)
+        if value is not None:
+            return parse_list(value)
 
     def get_dict(self, prefix):
         """

tests/test_conf.py

@@ -370,7 +370,7 @@ configure_logging = true
 
     def test_get_list(self):
         config = conf.WuttaConfig()
-        self.assertEqual(config.get_list('foo.bar'), [])
+        self.assertIsNone(config.get_list('foo.bar'))
         config.setdefault('foo.bar', 'hello world')
         self.assertEqual(config.get_list('foo.bar'), ['hello', 'world'])