Add dedicated splat mutator

Closes #66

lib/mutant.rb

@@ -69,6 +69,7 @@ require 'mutant/mutator/node/return'
 require 'mutant/mutator/node/block'
 require 'mutant/mutator/node/if'
 require 'mutant/mutator/node/case'
+require 'mutant/mutator/node/splat'
 require 'mutant/config'
 require 'mutant/loader'
 require 'mutant/context'

lib/mutant/mutator/node/generic.rb

@@ -12,7 +12,7 @@ module Mutant
           :zsuper, :not, :or, :and, :defined,
           :next, :break, :match, :gvar, :cvar, :ensure,
           :dstr, :dsym, :yield, :rescue, :redo, :defined?,
-          :lvar, :splat, :const, :blockarg, :block_pass, :op_asgn, :and_asgn,
+          :lvar, :const, :blockarg, :block_pass, :op_asgn, :and_asgn,
           :regopt, :ivar, :restarg, :casgn, :resbody, :retry, :arg_expr,
           :kwrestarg, :kwoptarg, :kwarg, :undef, :module, :cbase, :empty,
           :alias, :for, :xstr, :back_ref, :nth_ref, :class,

lib/mutant/mutator/node/splat.rb

@@ -0,0 +1,27 @@
+module Mutant
+  class Mutator
+    class Node
+      class Splat < self
+
+        handle :splat
+
+        children :expression
+
+      private
+
+        # Perform dispatch
+        #
+        # @return [undefined]
+        #
+        # @api private
+        #
+        def dispatch
+          emit_nil
+          emit_expression_mutations
+          emit(expression)
+        end
+
+      end # Splat
+    end # Node
+  end # Mutator
+end # Mutant

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

@@ -31,6 +31,8 @@ describe Mutant::Mutator, 'send' do
     let(:mutations) do
       mutations = []
       mutations << 'foo'
+      mutations << 'foo(nil)'
+      mutations << 'foo(bar)'
     end
 
     it_should_behave_like 'a mutator'