Add context identification

lib/mutant/context.rb

@@ -21,6 +21,14 @@ module Mutant
     #
     attr_reader :source_path
 
+    # Return identification
+    #
+    # @return [String]
+    #
+    # @api private
+    #
+    abstract_method :identification
+
   private
 
     # Initialize context

lib/mutant/context/scope.rb

@@ -16,6 +16,16 @@ module Mutant
         end
       end
 
+      # Return identification
+      #
+      # @return [String]
+      #
+      # @ai private
+      #
+      def identification
+        scope.name
+      end
+
       # Wrap node into ast node
       #
       # @param [Class, Module] scope