Restore back-command support
@@ -1153,6 +1153,7 @@ class VM:
cmd = self._vm._fetch_command()
if isinstance(cmd, InputSubmission):
self._buffer += cmd.data
+ self._processed_symbol_count += len(cmd.data)
elif isinstance(cmd, EOFCommand):
self._eof = True
elif isinstance(cmd, InlineCommand):
