NixOS Test Driver: Open Qemu with graphical output in driver interactive mode also on macOS (#391589)

nixos/lib/test-driver/src/test_driver/machine.py

@@ -1,6 +1,7 @@
 import base64
 import io
 import os
+import platform
 import queue
 import re
 import select
@@ -199,7 +200,13 @@ class StartCommand:
         allow_reboot: bool = False,
     ) -> str:
         display_opts = ""
+
         display_available = any(x in os.environ for x in ["DISPLAY", "WAYLAND_DISPLAY"])
+        if platform.system() == "Darwin":
+            # We have no DISPLAY variables on macOS and seemingly no better way
+            # to find out
+            display_available = "TERM_PROGRAM" in os.environ
+
         if not display_available:
             display_opts += " -nographic"