One of the fundamental methods share by both ActiveSupport and Facets
Hash#slice!. A few days ago, someone pointed out to me that the two
in this case are not quite the same. Quote, "I got hosed by a lovely
stemming from facets' and rails' slice! returning opposite things...
facets returns the key,value pairs not matched by the keys passed,
because it gives you two things back at once, though slice and slice!
return different things. rails returns the key,value pairs matched,
that is, slice and slice! have the same return"

Generally I let Facets defer to the behavior of ActiveSupport when
is a conflict, but in this case the Facets implementation seems more
useful and is also more in line to similar methods in core Ruby, ie.
Array#slice!, which also returns the deleted items.

So I was hoping that Rails could be modified to support this alternate
implementation of Hash#slice!.


We do have tests which assert that that's the result returned, but
they've been there from the beginning:


If you want to take a look at making that change, we can have a look
to see if it breaks anything else.

Ok. I've done it.

        # Replaces the hash with only the given keys.
        def slice!(*keys)
          keys = keys.map! { |key| convert_key(key) } if respond_to?
          omit = slice(*self.keys - keys)
          hash = slice(*keys)

I also updated the tests. Should I submit a patch? How do I proceed?


I also updated the tests. Should I submit a patch? How do I proceed?

You should create a patch following the guidelines we have on lighthouse:


Once that's done you can attach it to a new ticket and ask people for
feedback on it.

Done. Ticket #971.

Thanks for the help.