fail_with.rb in rspec-expectations-2.0.0.beta.12

- old
+ new
@@ -6,24 +6,42 @@
       end
       
       # raises a RSpec::Expectations::ExpectationNotMetError with message
       #
       # When a differ has been assigned and fail_with is passed
-      # <code>expected</code> and <code>target</code>, passes them
+      # <code>expected</code> and <code>actual</code>, passes them
       # to the differ to append a diff message to the failure message.
-      def fail_with(message, expected=nil, target=nil) # :nodoc:
-        if message.nil?
+      def fail_with(message, expected=nil, actual=nil) # :nodoc:
+        if !message
           raise ArgumentError, "Failure message is nil. Does your matcher define the " +
                                "appropriate failure_message_for_* method to return a string?"
         end
-        unless (differ.nil? || expected.nil? || target.nil?)
-          if expected.is_a?(String)
-            message << "\nDiff:" << self.differ.diff_as_string(target.to_s, expected)
-          elsif !target.is_a?(Proc)
-            message << "\nDiff:" << self.differ.diff_as_object(target, expected)
+
+        if actual && expected
+          if all_strings?(actual, expected)
+            if any_multiline_strings?(actual, expected)
+              message << "\nDiff:" << self.differ.diff_as_string(actual, expected)
+            end
+          elsif no_procs?(actual, expected)
+            message << "\nDiff:" << self.differ.diff_as_object(actual, expected)
           end
         end
-        Kernel::raise(RSpec::Expectations::ExpectationNotMetError.new(message))
+
+        raise(RSpec::Expectations::ExpectationNotMetError.new(message))
+      end
+
+    private
+
+      def no_procs?(*args)
+        args.none? {|a| Proc === a}
+      end
+
+      def all_strings?(*args)
+        args.all? {|a| String === a}
+      end
+
+      def any_multiline_strings?(*args)
+        all_strings?(*args) && args.any? {|a| a =~ /\n/}
       end
     end
   end
 end