[#698] Fix issue queries on Ruby 1.9

[mbreit]

This should fix the issue query problem described in #698. Query#values_for(field) returns an array which is passed to the text_field_tag helper method. This works on Ruby 1.8, because ["test"].to_s returns test, but on Ruby 1.9 it returns ["test"].

Using the first element of this array as parameter for text_field_tag seems better than relying on Array#to_s.

I did a quick test on Ruby 1.8.7 as well, it seems to work but it should be tested by someone else as well.

[thegcat]

Mmh, I'm not a huge fan on #try, any way to make it equally painless without try?

[thegcat]

(and thanks for the submission :-) )

[mbreit]

Query#values_for might return nil, so we have to check for that:

  def values_for(field)
    has_filter?(field) ? filters[field][:values] : nil
  end

We could write query.values_for(field).nil? ? nil : query.values_for(field) which (imho) reduces the readability and is exactly what try does. Another alternative would be to introduce a new variable, which is even worse from a readability point of view. It might make sense to change Query#values_for to return an empty array instead of nil, but I would try to avoid changing the API if there is no good test coverage.

But this is only my opinion and there are probably some other options which I don't see.

If you have another good idea or just another opinion, I will change it.

[thegcat]

The output of Query#values_for isn't really satisfactory and I'd have liked it better if the method presented correctly-formated values, but that's for another refactoring I guess. Thanks for the contribution!