Add range literal support

* Full of duplication. Will be addressed when all literals are done.

lib/mutant.rb

@@ -91,6 +91,8 @@ require 'mutant/mutator/float_literal'
 require 'mutant/mutator/array_literal'
 require 'mutant/mutator/empty_array'
 require 'mutant/mutator/hash_literal'
+require 'mutant/mutator/range'
+require 'mutant/mutator/range_exclude'
 require 'mutant/mutator/block'
 require 'mutant/loader'
 require 'mutant/context'

lib/mutant/mutator/range.rb

@@ -0,0 +1,53 @@
+module Mutant
+  class Mutator
+    class Range < Mutator
+    private
+
+      def mutants(generator)
+        generator << new_nil
+        generator << new(Rubinius::AST::RangeExclude,node.start,node.finish)
+
+        generator << new_self(neg_infinity,node.finish)
+        generator << new_self(nan,node.finish)
+        generator << new_self(node.start,infinity)
+        generator << new_self(node.start,nan)
+      end
+
+      # Return AST representing infinity
+      #
+      # @return [Rubinius::Node::AST]
+      #
+      # @api private
+      #
+      def neg_infinity
+        '-1.0/0.0'.to_ast.tap do |call|
+          call.line = node.line
+        end
+      end
+
+      # Return AST representing infinity
+      #
+      # @return [Rubinius::Node::AST]
+      #
+      # @api private
+      #
+      def infinity
+        '1.0/0.0'.to_ast.tap do |call|
+          call.line = node.line
+        end
+      end
+
+      # Return AST representing NaN
+      #
+      # @return [Rubinius::Node::AST]
+      #
+      # @api private
+      #
+      def nan
+        '0.0/0.0'.to_ast.tap do |call|
+          call.line = node.line
+        end
+      end
+    end
+  end
+end

lib/mutant/mutator/range_exclude.rb

@@ -0,0 +1,54 @@
+module Mutant
+  class Mutator
+    class RangeExclude < Mutator
+
+    private
+
+      def mutants(generator)
+        generator << new_nil
+        generator << new(Rubinius::AST::Range,node.start,node.finish)
+
+        generator << new_self(neg_infinity,node.finish)
+        generator << new_self(nan,node.finish)
+        generator << new_self(node.start,infinity)
+        generator << new_self(node.start,nan)
+      end
+
+      # Return AST representing infinity
+      #
+      # @return [Rubinius::Node::AST]
+      #
+      # @api private
+      #
+      def neg_infinity
+        '-1.0/0.0'.to_ast.tap do |call|
+          call.line = node.line
+        end
+      end
+
+      # Return AST representing infinity
+      #
+      # @return [Rubinius::Node::AST]
+      #
+      # @api private
+      #
+      def infinity
+        '1.0/0.0'.to_ast.tap do |call|
+          call.line = node.line
+        end
+      end
+
+      # Return AST representing NaN
+      #
+      # @return [Rubinius::Node::AST]
+      #
+      # @api private
+      #
+      def nan
+        '0.0/0.0'.to_ast.tap do |call|
+          call.line = node.line
+        end
+      end
+    end
+  end
+end

spec/unit/mutant/mutator/each_spec.rb

@@ -203,6 +203,38 @@ describe Mutant::Mutator, '#each' do
     it_should_behave_like 'a mutation enumerator method'
   end
 
+  context 'range literal' do
+    let(:source) { '1..100' } 
+
+    let(:mutations) do
+      mutations = []
+      mutations << 'nil'
+      mutations << '1...100'
+      mutations << '(0.0/0.0)..100'
+      mutations << '(-1.0/0.0)..100'
+      mutations << '1..(1.0/0.0)'
+      mutations << '1..(0.0/0.0)'
+    end
+
+    it_should_behave_like 'a mutation enumerator method'
+  end
+
+  context 'exclusive range literal' do
+    let(:source) { '1...100' } 
+
+    let(:mutations) do
+      mutations = []
+      mutations << 'nil'
+      mutations << '1..100'
+      mutations << '(0.0/0.0)...100'
+      mutations << '(-1.0/0.0)...100'
+      mutations << '1...(1.0/0.0)'
+      mutations << '1...(0.0/0.0)'
+    end
+
+    it_should_behave_like 'a mutation enumerator method'
+  end
+
   context 'block literal' do
     let(:source) { "true\nfalse" }