best_language fails to match language code against locale codes

[mttkay]

Not sure if this behavior is defined in the RFC, but the current implementation of language matching seems broken to me:

env = {'HTTP_ACCEPT_LANGUAGE' => 'en'}
req = Rack::Accept::Request.new(env)
req.best_language(%w(fr_fr en_gb))
=> nil

why does en_GB not match en? A client requesting just a language code, not a specific locale, is obviously only interested in the language part, not the country, so this should match all locale codes starting with en_*?

[mjackson]

The problem is in your example. The RFC for language tags specifies that locales should be separated from languages by a hyphen, not an underscore. If you change your example you'll get the proper result.

req.best_language(%w(fr-fr en-gb))
=> "en-gb"

[mttkay]

Oh dear, thanks! You're right of course. Fixed this in our backend. Sorry for the noise.

[mjackson]

No problem. Thank you for reporting what you thought was an issue. More eyes makes for better code!