Open splash as a separate rose command / process.

metomi/rose/gtk/splash.py

@@ -228,8 +228,7 @@ def _update_buffered(self, *args, **kwargs):
     __call__ = update
 
     def start(self):
-        file_name = __file__.rsplit(".", 1)[0] + ".py"
-        self.process = Popen([file_name] + list(self.args), stdin=PIPE)
+        self.process = Popen(" ".join(["rose launch-splash-screen"] + list(self.args)), shell=True, stdin=PIPE)
 
     def stop(self):
         if self.process is not None and not self.process.stdin.closed:
@@ -291,10 +290,10 @@ def _update_splash_screen(self, update_input):
         return False
 
 
-def main():
+def main(argv=sys.argv):
     """Start splash screen."""
     sys.path.append(os.getenv('ROSE_HOME'))
-    splash_screen = SplashScreen(*sys.argv[1:])
+    splash_screen = SplashScreen(argv[0], argv[1], argv[2])
     stop_event = threading.Event()
     update_thread = SplashScreenUpdaterThread(
         splash_screen, stop_event, sys.stdin)

setup.cfg

@@ -115,6 +115,7 @@ rose.commands =
     env-cat = metomi.rose.env_cat:main
     host-select = metomi.rose.host_select:main
     host-select-client = metomi.rose.host_select_client:main
+    launch-splash-screen = metomi.rose.gtk.splash:main
     macro = metomi.rose.macro:main
     metadata-check = metomi.rose.metadata_check:main
     metadata-gen = metomi.rose.metadata_gen:main