Only catch argparse exceptions on startup (Fixes #236)

Author: Casvt

Kapowarr.py

@@ -187,8 +187,13 @@ def Kapowarr() -> int:
                 db_folder=db_folder
             )
 
-        except ValueError:
-            parser.error("The value for -d/--DatabaseFolder is not a folder")
+        except ValueError as e:
+            if e.args and e.args[0] == 'Database location is not a folder':
+                parser.error(
+                    "The value for -d/--DatabaseFolder is not a folder"
+                )
+            else:
+                raise e
 
     else:
         rc = Kapowarr()

backend/internals/db.py

@@ -169,7 +169,7 @@ def set_db_location(
 
     if db_folder:
         if exists(db_folder) and not isdir(db_folder):
-            raise ValueError
+            raise ValueError('Database location is not a folder')
 
     db_file_location = join(
         db_folder or folder_path(*Constants.DB_FOLDER),