Add mutator for next nodes

lib/mutant.rb

@@ -72,6 +72,7 @@ require 'mutant/mutator/node/dsym'
 require 'mutant/mutator/node/named_value/access'
 require 'mutant/mutator/node/named_value/constant_assignment'
 require 'mutant/mutator/node/named_value/variable_assignment'
+require 'mutant/mutator/node/next'
 require 'mutant/mutator/node/noop'
 require 'mutant/mutator/node/op_asgn'
 require 'mutant/mutator/node/while'

lib/mutant/mutator/node/generic.rb

@@ -10,7 +10,7 @@ module Mutant
         # These nodes still need a dedicated mutator,
         # your contribution is that close!
         handle(
-          :next, :ensure,
+          :ensure,
           :rescue, :redo, :defined?,
           :regopt, :resbody, :retry, :arg_expr,
           :kwrestarg, :kwoptarg, :kwarg, :undef, :module, :empty,

lib/mutant/mutator/node/next.rb

@@ -0,0 +1,30 @@
+# encoding: utf-8
+
+module Mutant
+  class Mutator
+    class Node
+
+      # Next mutator
+      class Next < Generic
+
+        handle(:next)
+
+      private
+
+        # Emit mutations
+        #
+        # @return [undefined]
+        #
+        # @api private
+        #
+        def dispatch
+          super
+          children.each_index(&method(:delete_child))
+          emit(s(:break, *children))
+          emit_nil
+        end
+
+      end # Next
+    end # Node
+  end # Mutator
+end # Mutant

spec/unit/mutant/mutator/node/next/mutation_spec.rb

@@ -2,13 +2,16 @@
 
 require 'spec_helper'
 
-describe Mutant::Mutator::Node::Generic, 'next' do
+describe Mutant::Mutator::Node::Next, 'next' do
   let(:source)  { 'next true' }
 
   let(:mutations) do
     mutations = []
     mutations << 'next false'
     mutations << 'next nil'
+    mutations << 'next'
+    mutations << 'nil'
+    mutations << 'break true'
   end
 
   it_should_behave_like 'a mutator'