Cleanup node body mutation

config/flay.yml

@@ -1,3 +1,3 @@
 ---
 threshold: 18
-total_score: 728
+total_score: 750

lib/mutant/mutator/node.rb

@@ -103,56 +103,24 @@ module Mutant
         end
       end
 
-      # Emit element presence mutations
-      #
-      # @param [Array] elements
-      #
-      # @return [undefined]
-      #
-      # @api private
-      #
-      def emit_element_presence(elements)
-        elements.each_index do |index|
-          dup_elements = elements.dup
-          dup_elements.delete_at(index)
-          emit_self(dup_elements)
-        end
-      end
-
       # Emit body mutations
       #
+      # @param [Symbol] name
+      #
       # @return [undefined]
       #
       # @api private
       #
-      def emit_mutate_attributes(method)
-        body = node.public_send(method)
+      def emit_attribute_mutations(name)
+        body = node.public_send(name)
 
         Mutator.each(body) do |mutation|
           dup = dup_node
-          dup.public_send(:"#{method}=", mutation)
+          dup.public_send(:"#{name}=", mutation)
           emit(dup)
         end
       end
 
-      # Emit body mutations
-      #
-      # @param [Array] body
-      #
-      # @return [undefined]
-      #
-      # @api private
-      #
-      def emit_body(body)
-        body.each_with_index do |element, index|
-          dup_body = body.dup
-          Mutator.each(element).each do |mutation|
-            dup_body[index]=mutation
-            emit_self(dup_body)
-          end
-        end
-      end
-
       # Emit a new AST node with NilLiteral class
       #
       # @return [Rubinius::AST::NilLiteral]

lib/mutant/mutator/node/arguments.rb

@@ -15,7 +15,7 @@ module Mutant
         # @api private
         #
         def dispatch
-          emit_mutate_attributes(:array)
+          emit_attribute_mutations(:array)
         end
 
       end

lib/mutant/mutator/node/block.rb

@@ -16,12 +16,7 @@ module Mutant
         #
         def dispatch
           array = input.array
-          emit_body(array)
-          if array.length > 1
-            emit_element_presence(array)
-          else
-            emit_self([new_nil])
-          end
+          emit_attribute_mutations(:array)
         end
       end
     end

lib/mutant/mutator/node/define.rb

@@ -16,7 +16,7 @@ module Mutant
         # @api private
         #
         def dispatch
-          emit_mutate_attributes(:body)
+          emit_attribute_mutations(:body)
         end
       end
     end

lib/mutant/mutator/node/if_statement.rb

@@ -15,9 +15,9 @@ module Mutant
         # @api private
         #
         def dispatch
-          emit_mutate_attributes(:condition)
-          emit_mutate_attributes(:body)
-          emit_mutate_attributes(:else) if node.else
+          emit_attribute_mutations(:condition)
+          emit_attribute_mutations(:body)
+          emit_attribute_mutations(:else) if node.else
           emit_inverted_condition 
           emit_deleted_if_branch
           emit_deleted_else_branch

lib/mutant/mutator/node/literal/array.rb

@@ -16,12 +16,10 @@ module Mutant
           # @api private
           #
           def dispatch
-            body = node.body
-            emit_nil
+            emit_attribute_mutations(:body)
             emit_self([])
-            emit_self(body.dup << new_nil)
-            emit_element_presence(body)
-            emit_body(body)
+            emit_nil
+            emit_self(node.body.dup << new_nil)
           end
         end
       end

lib/mutant/mutator/node/literal/hash.rb

@@ -19,7 +19,25 @@ module Mutant
             emit_nil
             emit_values(values)
             emit_element_presence
-            emit_body(array)
+            emit_array
+          end
+
+          # Emit body mutations
+          #
+          # @param [Array] body
+          #
+          # @return [undefined]
+          #
+          # @api private
+          #
+          def emit_array
+            array.each_with_index do |element, index|
+              dup = dup_array
+              Mutator.each(element).each do |mutation|
+                dup[index]=mutation
+                emit_self(dup)
+              end
+            end
           end
 
           # Return array of values in literal

lib/mutant/mutator/node/receiver_case.rb

@@ -15,7 +15,7 @@ module Mutant
         # @api private
         #
         def dispatch
-          emit_mutate_attributes(:body)
+          emit_attribute_mutations(:body)
         end
 
       end
@@ -34,7 +34,7 @@ module Mutant
         # @api private
         #
         def dispatch
-          emit_mutate_attributes(:receiver)
+          emit_attribute_mutations(:receiver)
           emit_when_branch_presence_mutations
           emit_else_branch_presence_mutation
           emit_when_branch_mutations

lib/mutant/mutator/node/send.rb

@@ -102,7 +102,7 @@ module Mutant
           #
           def dispatch
             super
-            emit_mutate_attributes(:arguments)
+            emit_attribute_mutations(:arguments)
           end
 
         end

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

@@ -15,6 +15,7 @@ describe Mutant::Mutator, 'block' do
      ## Remove statement in block
       mutations << [:block, 'self.foo'.to_sexp]
       mutations << [:block, 'self.bar'.to_sexp]
+      mutations << [:block]
     end
 
     it_should_behave_like 'a mutator'
@@ -27,8 +28,7 @@ describe Mutant::Mutator, 'block' do
     let(:mutations) do
       mutations = []
       mutations << [:block, 'foo'.to_sexp]
-      # Empty blocks result in stack verification error
-      mutations << [:block, 'nil'.to_sexp]
+      mutations << [:block]
     end
 
     it_should_behave_like 'a mutator'

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

@@ -15,6 +15,9 @@ describe Mutant::Mutator, 'define' do
       # Remove statement in block
       mutations << 'def foo; self.baz; end'
       mutations << 'def foo; self.bar; end'
+
+      # Remove all statements
+      mutations << [:defn, :foo, [:args], [:scope, [:block]]]
     end
 
     it_should_behave_like 'a mutator'
@@ -33,6 +36,9 @@ describe Mutant::Mutator, 'define' do
       # Body presence mutations
       mutations << 'def self.foo; self.bar; end'
       mutations << 'def self.foo; self.baz; end'
+
+      # Remove all statements
+      mutations << [:defs, [:self], :foo, [:args], [:scope, [:block]]]
     end
 
     it_should_behave_like 'a mutator'