gdb: Migrate vo command to Python gdb script

gdb/.gdbinit.d/init

@@ -11,15 +11,3 @@ set mi-async on
 set non-stop off
 
 alias -a it = info threads
-
-# Adapted to use neovim from https://github.com/cyrus-and/gdb-dashboard/issues/20
-define vo
-python
-import os
-sal = gdb.selected_frame().find_sal()
-current_line = sal.line
-if current_line != 0:
-    openInNvim = "nvr +" + str(current_line) + " " + sal.symtab.fullname()
-    os.system(openInNvim)
-end
-end

gdb/.gdbinit.d/scripts/vo.py

@@ -0,0 +1,21 @@
+# Adapted to use neovim from https://github.com/cyrus-and/gdb-dashboard/issues/20
+# Requires neovim-remote and can only be used from within neovim terminal
+import os
+import gdb  # type: ignore
+
+
+class OpenNvim(gdb.Command):
+    def __init__(self):
+        super().__init__("vo", gdb.COMMAND_USER)
+
+    def complete(self, _text, _word):
+        return gdb.COMPLETE_SYMBOL
+
+    def invoke(self, _args, _from_tty):
+        sal = gdb.selected_frame().find_sal()
+        current_line = sal.line
+        if current_line != 0:
+            openInNvim = "nvr +" + str(current_line) + " " + sal.symtab.fullname()
+            os.system(openInNvim)
+
+OpenNvim()