nixos-rebuild-ng: validate NIX_SSHOPTS only once

pkgs/by-name/ni/nixos-rebuild-ng/src/nixos_rebuild/__init__.py

@@ -139,7 +139,9 @@ def parse_args(
         Action.SWITCH.value,
         Action.BOOT.value,
     ):
-        parser.error(f"--target-host/--build-host is not supported with '{args.action}'")
+        parser.error(
+            f"--target-host/--build-host is not supported with '{args.action}'"
+        )
 
     if args.flake and (args.file or args.attr):
         parser.error("--flake cannot be used with --file or --attr")
@@ -166,7 +168,9 @@ def execute(argv: list[str]) -> None:
     atexit.register(cleanup_ssh, tmpdir_path)
 
     profile = Profile.from_arg(args.profile_name)
-    build_host = Remote.from_arg(args.build_host, False, tmpdir_path)
+    build_host = Remote.from_arg(
+        args.build_host, False, tmpdir_path, validate_opts=False
+    )
     target_host = Remote.from_arg(args.target_host, args.ask_sudo_password, tmpdir_path)
     build_attr = BuildAttr.from_arg(args.attr, args.file)
     flake = Flake.from_arg(args.flake, target_host)

pkgs/by-name/ni/nixos-rebuild-ng/src/nixos_rebuild/process.py

@@ -22,12 +22,14 @@ class Remote:
         host: str | None,
         ask_sudo_password: bool | None,
         tmp_dir: Path,
+        validate_opts: bool = True,
     ) -> Self | None:
         if not host:
             return None
 
         opts = os.getenv("NIX_SSHOPTS", "").split()
-        cls._validate_opts(opts, ask_sudo_password)
+        if validate_opts:
+            cls._validate_opts(opts, ask_sudo_password)
         opts += [
             # SSH ControlMaster flags, allow for faster re-connection
             "-o",