fixing assert_difference issues on ruby 1.8

activesupport/lib/active_support/testing/assertions.rb

@@ -45,18 +45,19 @@ module Assertions
       #     post :delete, :id => ...
       #   end
       def assert_difference(expression, difference = 1, message = nil, &block)
-        exps = Array.wrap(expression).map { |e|
-          callee = e.respond_to?(:call) ? e : lambda { eval(e, block.binding) }
-          [e, callee]
+        expressions = Array.wrap expression
+
+        exps = expressions.map { |e|
+          e.respond_to?(:call) ? e : lambda { eval(e, block.binding) }
         }
-        before = exps.map { |_, block| block.call }
+        before = exps.map { |e| e.call }
 
         yield
 
-        exps.each_with_index do |(code, block), i|
+        expressions.zip(exps).each_with_index do |(code, e), i|
           error  = "#{code.inspect} didn't change by #{difference}"
           error  = "#{message}.\n#{error}" if message
-          assert_equal(before[i] + difference, block.call, error)
+          assert_equal(before[i] + difference, e.call, error)
         end
       end