Allows you set available formats with hyphens but lookups fail

[mcfilib]

When I use IETF Language Tags instead of POSIX locales in .default_available_locales, fast_gettext formats the hyphen to an underscore when calling .set_locale.

I came across this when trying to use IETF Language Tags instead of POSIX locales in a Rails application and I'm wondering if you could offer some clarification as to whether this is the expected behaviour or whether there might be some room for improvement.

Reproduction Steps

[12] pry(#<DashboardController>)> FastGettext.default_available_locales = ["en-GB", "es-ES"]
=> ["en-GB", "es-ES"]
[13] pry(#<DashboardController>)> FastGettext.available_locales
=> ["en-GB", "es-ES"]
[14] pry(#<DashboardController>)> FastGettext.set_locale("es-ES")
=> "en-GB"

This happens because FastGettext formats my input using #set_locale, replacing the hyphen with an underscore, before doing a lookup on the available locales e.g.

[15] pry(#<DashboardController>)> FastGettext.send(:formatted_sorted_locales, "es-ES")
=> ["es_ES"]
[16] pry(#<DashboardController>)> FastGettext.available_locales.include?("es_ES")
=> false

Question

Should FastGettext be replacing hyphens at all? Is this behaviour also present in gettext?

[mcfilib]

Here's a link the issue which gives more context webhippie/gettext_i18n_rails_js#31.

[grosser]

afaik this is expected behavior since po files use underscores and rails wants to use - ... so conversion was added

[grosser]

the usage you showed above looks broken though ... so there definitely is room for improvement :/