Ruby 1.9.3 hash syntax not working with rspec-rails 2.9?

I have a Rails 3.2 project I just started, and I'm trying to write some tests.

When I try to utilize Ruby 1.9.3's JSON-esque hash syntax and do this:

let(:user) { User.new(first_name: 'Joe', last_name: 'Blow') }
 

or this:

let(:user) { User.new({first_name: 'Joe', last_name: 'Blow'}) }
 

I get this error:

syntax error, unexpected ':', expecting ')' (SyntaxError)
   let(:user) { User.new(first_name: 'Joe', last_name: 'Blow') }
                                    ^
 

When I revert to the :key => 'value' syntax, rspec then looks at the user.rb file I'm requiring and says it doesn't know what is going on with the syntax present there, either.

Is there a way I can remedy this?

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