Add portable mode

If settings.ini is present next to the executable, will run in portable mode.
This results in settings, data, and cache all being in same folder as dupeGuru.

qtlib/preferences.py

@@ -12,6 +12,7 @@ from PyQt5.QtWidgets import QDockWidget
 from hscommon.trans import trget
 from hscommon.util import tryint
 from hscommon.plat import ISWINDOWS
+from core.util import executable_folder
 
 from os import path as op
 
@@ -68,18 +69,25 @@ def adjust_after_deserialization(v):
     return v
 
 
-def createQSettings():
+def create_qsettings():
     # Create a QSettings instance with the correct arguments.
-    # On windows use an ini file in the AppDataLocation instead of registry if possible as it
-    # makes it easier for a user to clear it out when there are issues.
-    if ISWINDOWS:
-        Locations = QStandardPaths.standardLocations(QStandardPaths.AppDataLocation)
-        if Locations:
-            return QSettings(op.join(Locations[0], "settings.ini"), QSettings.IniFormat)
+    config_location = op.join(executable_folder(), "settings.ini")
+    if op.isfile(config_location):
+        settings = QSettings(config_location, QSettings.IniFormat)
+        settings.setValue("Portable", True)
+    elif ISWINDOWS:
+        # On windows use an ini file in the AppDataLocation instead of registry if possible as it
+        # makes it easier for a user to clear it out when there are issues.
+        locations = QStandardPaths.standardLocations(QStandardPaths.AppDataLocation)
+        if locations:
+            settings = QSettings(op.join(locations[0], "settings.ini"), QSettings.IniFormat)
         else:
-            return QSettings()
+            settings = QSettings()
+        settings.setValue("Portable", False)
     else:
-        return QSettings()
+        settings = QSettings()
+        settings.setValue("Portable", False)
+    return settings
 
 
 # About QRect conversion:
@@ -93,7 +101,7 @@ class Preferences(QObject):
     def __init__(self):
         QObject.__init__(self)
         self.reset()
-        self._settings = createQSettings()
+        self._settings = create_qsettings()
 
     def _load_values(self, settings, get):
         pass

qtlib/util.py

@@ -12,6 +12,7 @@ import os.path as op
 import os
 import logging
 
+from core.util import executable_folder
 from hscommon.util import first
 
 from PyQt5.QtCore import QStandardPaths
@@ -88,8 +89,11 @@ def setAccelKeys(menu):
         action.setText(newtext)
 
 
-def getAppData():
-    return QStandardPaths.standardLocations(QStandardPaths.DataLocation)[0]
+def getAppData(portable=False):
+    if portable:
+        return op.join(executable_folder(), "data")
+    else:
+        return QStandardPaths.standardLocations(QStandardPaths.AppDataLocation)[0]
 
 
 class SysWrapper(io.IOBase):