Don't fail if the theme doesn't have a data dir

[fauno]

When the theme doesn't have a data dir the File.join fails because the path is nil

[ashmaroli]

@fauno I'm not against this change but would like to know why one would use this plugin if the theme they're using doesn't have a _data directory at theme-root..?

[fauno]

hi! so i'm building a self managed control panel for jekyll and one of the features is that you can exchange themes. i needed jekyll-data so i can load locales and other data templates from the theme (thanks!)

i was testing changing from minima to a custom theme, but jekyll-data would fail because minima doesn't have a _data directory. in your case, maybe a user is testing the plugin with such a theme? without this patch the build fails entirely.

[ashmaroli]

Thanks for sharing your use-case.

Okay, regarding your implementation here, I don't think you need to add that safe navigation operator in method :inspect_theme_data if there are no data files in the theme..
If you look at method :read_theme_data, you'll see that the whole definition is wrapped in a conditional.

I haven't tested this branch at my end yet, so if you think the safe navigation operator is necessary, and I missed something, do let me know.

[fauno]

no, you're right. i did wonder why read_theme_data was conditional but @theme_data_files wasn't :)

[ashmaroli]

Thank you @fauno!!