Add global, local and instance variable assignment mutators

lib/mutant.rb

@@ -83,6 +83,7 @@ require 'mutant/mutator/node/literal/nil'
 require 'mutant/mutator/node/block'
 require 'mutant/mutator/node/noop'
 require 'mutant/mutator/node/send'
+require 'mutant/mutator/node/assignment'
 require 'mutant/mutator/node/define'
 require 'mutant/mutator/node/formal_arguments_19'
 require 'mutant/mutator/node/formal_arguments_19/default_mutations'
@@ -93,7 +94,6 @@ require 'mutant/mutator/node/pattern_arguments'
 require 'mutant/mutator/node/pattern_variable'
 require 'mutant/mutator/node/default_arguments'
 require 'mutant/mutator/node/return'
-require 'mutant/mutator/node/local_variable_assignment'
 require 'mutant/mutator/node/iter_19'
 require 'mutant/mutator/node/if_statement'
 require 'mutant/mutator/node/receiver_case'

lib/mutant/mutator/node/assignment.rb

@@ -0,0 +1,48 @@
+module Mutant
+  class Mutator
+    class Node
+      class Assignment < self
+
+      private
+
+        class Variable < self
+
+          # Emit mutants
+          #
+          # @return [undefined]
+          #
+          # @api private
+          #
+          def dispatch
+            emit_attribute_mutations(:name) do |mutation|
+              mutation.name = "#{self.class::PREFIX}#{mutation.name}".to_sym
+            end
+            emit_attribute_mutations(:value)
+          end
+
+          class Local < self
+            PREFIX = ''.freeze
+            handle(Rubinius::AST::LocalVariableAssignment)
+          end
+
+          class Instance < self
+            PREFIX = '@'.freeze
+            handle(Rubinius::AST::InstanceVariableAssignment)
+          end
+
+          class Class < self
+            PREFIX = '@@'.freeze
+            handle(Rubinius::AST::ClassVariableAssignment)
+          end
+
+          class Global < self
+            PREFIX = '$'.freeze
+            handle(Rubinius::AST::GlobalVariableAssignment)
+          end
+
+        end
+
+      end
+    end
+  end
+end

lib/mutant/mutator/node/local_variable_assignment.rb

@@ -1,25 +0,0 @@
-module Mutant
-  class Mutator
-    class Node 
-      class LocalVariableAssignment < self
-
-        handle(Rubinius::AST::LocalVariableAssignment)
-
-      private
-
-        # Emit mutants
-        #
-        # @return [undefined]
-        #
-        # @api private
-        #
-        def dispatch
-          emit_attribute_mutations(:name)
-          emit_attribute_mutations(:value)
-        end
-
-      end
-    end
-  end
-end
-

lib/mutant/mutator/node/noop.rb

@@ -22,12 +22,11 @@ module Mutant
         handle(Rubinius::AST::ZSuper)
         handle(Rubinius::AST::MultipleAssignment)
         handle(Rubinius::AST::ScopedConstant)
-        handle(Rubinius::AST::LocalVariableAssignment)
         handle(Rubinius::AST::LocalVariableAccess)
         handle(Rubinius::AST::InstanceVariableAssignment)
         handle(Rubinius::AST::InstanceVariableAccess)
-        handle(Rubinius::AST::GlobalVariableAssignment)
         handle(Rubinius::AST::GlobalVariableAccess)
+        handle(Rubinius::AST::ClassVariableAccess)
         handle(Rubinius::AST::ToplevelConstant)
         handle(Rubinius::AST::Ensure)
         handle(Rubinius::AST::Rescue)

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

@@ -0,0 +1,64 @@
+require 'spec_helper'
+
+describe Mutant::Mutator::Node::Assignment, 'mutations' do
+
+  before do
+    Mutant::Random.stub(:hex_string => :random)
+  end
+
+  context 'global variable' do
+    let(:source) { '$a = true' }
+
+    let(:mutations) do
+      mutations = []
+
+      mutations << '$srandom = true'
+      mutations << '$a = false'
+      mutations << '$a = nil'
+    end
+
+    it_should_behave_like 'a mutator'
+  end
+
+  context 'class variable' do
+    let(:source) { '@@a = true' }
+
+    let(:mutations) do
+      mutations = []
+
+      mutations << '@@srandom = true'
+      mutations << '@@a = false'
+      mutations << '@@a = nil'
+    end
+
+    it_should_behave_like 'a mutator'
+  end
+
+  context 'instance variable' do
+    let(:source) { '@a = true' }
+
+    let(:mutations) do
+      mutations = []
+
+      mutations << '@srandom = true'
+      mutations << '@a = false'
+      mutations << '@a = nil'
+    end
+
+    it_should_behave_like 'a mutator'
+  end
+
+  context 'local variable' do
+    let(:source) { 'a = true' }
+
+    let(:mutations) do
+      mutations = []
+
+      mutations << 'srandom = true'
+      mutations << 'a = false'
+      mutations << 'a = nil'
+    end
+
+    it_should_behave_like 'a mutator'
+  end
+end