__writeApplicationStarter() crashes when no server config exists

[mindjuice]

The following line crashes when your mimosa-config file has no server entries:

serverRelPath = config.server.path.split(config.root)[1].substr(1);

See https://github.com/dbashford/mimosa-web-package/blob/master/src/index.coffee#L174

A workaround is to set the following in your mimosa-config.coffee (or the equivalent in your mimosa-config.js):

webPackage:
  appjs: undefined

If you run into this problem, it's probably because you don't actually have a server to run, so adding the above to your config is something you should do anyway, but Mimosa shouldn't crash if you setup your config incorrectly.

I would just patch this and submit a PR, but I'm not sure what the value of serverRelPath should be if server is not defined. Just "." maybe?

[dbashford]

I think the larger issue is... if you don't have a server, you don't need app.js. Probably a safe assumption, ya?

So in config.coffee, the validate method could check to see if there is a server config, and if not, set config.webPackage.appjs to null.

[mindjuice]

Agreed. That should work. I can add a line to the validate method and submit a PR.