Add --dry-run option to just print command line (python3.8+)

src/rktlnch.py

@@ -6,7 +6,7 @@
 import json
 import os
 import shlex
-from sys import exit as _exit
+from sys import exit as _exit, version_info
 
 from base64 import b64decode, b64encode
 
@@ -34,6 +34,10 @@ def exit(code=0):
     parser.add_argument('--override-username', dest='user_name_override', action='store',
                         help='Override epic username')
 
+    if version_info.minor >= 8:
+        parser.add_argument('--dry-run', dest='just_print', action='store_true',
+                            default=False, help='Do not launch, just print the command line and exit.')
+
     args, extra = parser.parse_known_args()
 
     elfs = EPCLFS()
@@ -152,6 +156,10 @@ def exit(code=0):
         print('Adding extra params:', ', '.join(extra))
         params.extend(extra)
 
+    if version_info.minor >= 8 and args.just_print:
+        print('Launch command:', shlex.join(params))
+        exit(0)
+
     try:
         # Launching the game!
         print('Launching the game... ', end='', flush=True)