The absence of labels in these controls made them hard to use,
particularly for people who use screen readers.
Note we're removing the "Choose language" prompt, since we always
automatically choose a language and not choosing a language doesn't
really make sense. The only scenario where the prompt was used took
place when all languages had been removed but, in that case, the "Choose
language" prompt was misleading because there were no languages to
choose from.
Note that, currently, we take these settings from the database but we
don't provide a way to edit them through the admin interface, so the
locales must be manually introduced through a Rails console.
While we did consider using a comma-separated list, we're using spaces
in order to be consistent with the way we store the allowed content
types settings.
The `enabled_locales` nomenclature, which contrasts with
`available_locales`, is probably subconsciously based on similar
patterns like the one Nginx uses to enable sites.
Note that we aren't using `Setting.enabled_locales` in the globalize
initializer when setting the fallbacks. This means the following test
(which we could add to the shared globalizable examples) would fail:
```
it "Falls back to an enabled locale if the fallback is not enabled" do
Setting["locales.default"] = "en"
Setting["locales.enabled"] = "fr en"
allow(I18n.fallbacks).to receive(:[]).and_return([:fr, :es])
Globalize.set_fallbacks_to_all_available_locales
I18n.with_locale(:fr) do
expect(record.send(attribute)).to eq "In English"
end
end
```
The reason is that the code making this test pass could be:
```
def Globalize.set_fallbacks_to_all_available_locales
Globalize.fallbacks = I18n.available_locales.index_with do |locale|
((I18n.fallbacks[locale] & Setting.enabled_locales) + Setting.enabled_locales).uniq
end
end
```
However, this would make it impossible to run `rake db:migrate` on new
applications because the initializer would try to load the `Setting`
model but the `settings` table wouldn't exist at that point.
Besides, this is a really rare case that IMHO we don't need to support.
For this scenario, an installation would have to enable a locale, create
records with contents in that locale, then disable that locale and have
that locale as a fallback for a language where content for that record
wasn't created. If that happened, it would be solved by creating content
for that record in every enabled language.
