Fixed bug rendering no diff indicator as JSON

Author: bethesque

.rspec

@@ -1,2 +1,3 @@
 --color
 --format documentation
+--require spec_helper

lib/pact/matchers/no_diff_indicator.rb

@@ -3,7 +3,7 @@ module Matchers
     class NoDiffIndicator
 
       def to_json options = {}
-        to_s
+        to_s.inspect
       end
 
       def to_s
@@ -15,4 +15,4 @@ def == other
       end
     end
   end
-end
+end

spec/lib/pact/matchers/no_diff_indicator_spec.rb

@@ -0,0 +1,15 @@
+require 'pact/matchers/no_diff_indicator'
+
+module Pact
+  module Matchers
+    describe NoDiffIndicator do
+
+      describe "#to_json" do
+        it "returns a json string" do
+          expect(NoDiffIndicator.new.to_json).to eq '"no difference here!"'
+        end
+      end
+
+    end
+  end
+end