Node changed their repl so that it inherits from readline.Interface.
This means that `prompt` is now the rli function and not the original
prompt string. This may be a little hacky, but I figure it would give
someone a start if they want to do a better fix.
The commit that changed this in Node is nodejs/node-v0.x-archive@3ae0b17
This bug was mentioned in Issue #3395.