Fix 1416703

openlp/core/common/settings.py

@@ -45,6 +45,13 @@ if is_linux():
         X11_BYPASS_DEFAULT = False
 
 
+def recent_files_conv(value):
+    if isinstance(value, list):
+        return value
+    elif isinstance(value, str):
+        return [value]
+
+
 class Settings(QtCore.QSettings):
     """
     Class to wrap QSettings.
@@ -328,7 +335,7 @@ class Settings(QtCore.QSettings):
         ('general/language', 'core/language', []),
         ('general/last version test', 'core/last version test', []),
         ('general/loop delay', 'core/loop delay', []),
-        ('general/recent files', 'core/recent files', []),
+        ('general/recent files', 'core/recent files', [(recent_files_conv, None)]),
         ('general/save prompt', 'core/save prompt', []),
         ('general/screen blank', 'core/screen blank', []),
         ('general/show splash', 'core/show splash', []),
@@ -410,7 +417,9 @@ class Settings(QtCore.QSettings):
                     for new, old in rules:
                         # If the value matches with the condition (rule), then use the provided value. This is used to
                         # convert values. E. g. an old value 1 results in True, and 0 in False.
-                        if old == old_value:
+                        if callable(new):
+                            old_value = new(old_value)
+                        elif old == old_value:
                             old_value = new
                             break
                     self.setValue(new_key, old_value)

tests/functional/openlp_core_common/test_settings.py

@@ -25,6 +25,7 @@ Package to test the openlp.core.lib.settings package.
 from unittest import TestCase
 
 from openlp.core.common import Settings
+from tests.functional import patch
 from tests.helpers.testmixin import TestMixin
 
 
@@ -120,3 +121,11 @@ class TestSettings(TestCase, TestMixin):
 
         # THEN: An exception with the non-existing key should be thrown
         self.assertEqual(str(cm.exception), "'core/does not exists'", 'We should get an exception')
+
+    def extend_default_settings_test(self):
+        with patch.dict(Settings() .__default_settings__, {1: 2, 3: 4}, clear=True):
+            Settings().extend_default_settings({'a': 'b', 'c': 'd'})
+
+            ds = Settings().__default_settings__
+
+            self.assertDictEqual(ds, {1: 2, 3: 4, 'a': 'b', 'c': 'd'})