Use eval to avoid SyntaxError on Ruby 1.9.3

Author: mame

spec/rspec/mocks/partial_double_spec.rb

@@ -81,10 +81,12 @@ def call(name)
         expect(object.foobar(:key => "value")).to equal(1)
       end
 
-      it "can accept an inner hash as a message argument" do
-        hash = {:a => {:key => "value"}}
-        expect(object).to receive(:foobar).with(:key => "value").and_return(1)
-        expect(object.foobar(**hash[:a])).to equal(1)
+      if RSpec::Support::RubyFeatures.required_kw_args_supported?
+        it "can accept an inner hash as a message argument" do
+          hash = {:a => {:key => "value"}}
+          expect(object).to receive(:foobar).with(:key => "value").and_return(1)
+          expect(object.foobar(**hash[:a])).to equal(1)
+        end
       end
 
       it "can create a positive message expectation" do