svenfuchs/i18n — pull request #166 by henrik (2012-09-16 12:00:11+00:00)
Title: Include the missing key in "missing interpolation argument" errors.

It's a bit annoying to manually compare the passed-in hash to the arguments, so we fixed it. Hope you'll merge.

Some things I noticed:

`test/i18n/exceptions_test.rb` had a commented-out test about including the missing key in an exception accessor. Couldn't figure out from git blame why it was commented out in the first place ("cleanup"), so I restored it.

`backend/interpolation_compiler.rb` did this:

``` ruby
def missing_key(key)
"raise(MissingInterpolationArgument.new(#{key}, self))"
end
```

That looks like forgotten, possibly dead code. Before my pull request, the actual method profile was `values, string`; the key wasn't passed. I just modified it to pass `{}` for values, so it's about as broken as it was, but that class should probably be reviewed.