Add concat-promotion of resbody nodes

Idea related to #245.

Changelog.md

@@ -1,6 +1,7 @@
 # v0.6.1 2014-08-16
 
-* Add rescue else body promotion/concatenation mutation
+* Add rescue resbody body concat-promotion mutation
+* Add rescue else body concat-promotion mutation #245
 
 # v0.6.0 2014-08-11
 

config/flay.yml

@@ -1,3 +1,3 @@
 ---
 threshold: 18
-total_score: 1076
+total_score: 1085

lib/mutant/ast/meta.rb

@@ -17,14 +17,42 @@ module Mutant
         REGISTRY.fetch(node.type, Generic).new(node)
       end
 
-      # Generic metadata for send nodes
+      # Mixin to define meta nodes
+      class Node < Module
+        include Concord.new(:type)
+
+        CONCORD = Concord.new(:node)
+
+        # Hook called when module gets included
+        #
+        # @param [Class, Module] host
+        #
+        # @return [undefined]
+        #
+        # @api private
+        #
+        def included(host)
+          REGISTRY[type] = host
+          host.class_eval do
+            include CONCORD, NamedChildren
+          end
+        end
+
+      end # Node
+
+      # Metadata for resbody nods
+      class Resbody
+        include Node.new(:resbody)
+
+        children :captures, :assignment, :body
+      end # Resbody
+
+      # Metadata for send nodes
       class Send
-        include Concord.new(:node), NamedChildren
+        include Node.new(:send)
 
         children :receiver, :selector
 
-        REGISTRY[:send] = self
-
         INDEX_ASSIGNMENT_SELECTOR            = :[]=
         ATTRIBUTE_ASSIGNMENT_SELECTOR_SUFFIX = '='.freeze
 

lib/mutant/meta.rb

@@ -16,7 +16,8 @@ module Mutant
       # @api private
       #
       def self.add(&block)
-        ALL << DSL.run(block)
+        file = caller.first.split(':in', 2).first
+        ALL << DSL.run(file, block)
       end
 
       Pathname.glob(Pathname.new(__FILE__).parent.parent.parent.join('meta', '**/*.rb'))

lib/mutant/meta/example.rb

@@ -1,7 +1,7 @@
 module Mutant
   module Meta
     class Example
-      include Adamantium, Concord::Public.new(:node, :mutations)
+      include Adamantium, Concord::Public.new(:file, :node, :mutations)
 
       # Return a verification instance
       #
@@ -97,7 +97,7 @@ module Mutant
         def mutation_report
           original_node = example.node
           [
-            'Original-AST:',
+            "#{example.file}, Original-AST:",
             original_node.inspect,
             'Original-Source:',
             example.source,

lib/mutant/meta/example/dsl.rb

@@ -12,8 +12,8 @@ module Mutant
         #
         # @api private
         #
-        def self.run(block)
-          instance = new
+        def self.run(file, block)
+          instance = new(file)
           instance.instance_eval(&block)
           instance.example
         end
@@ -24,7 +24,8 @@ module Mutant
         #
         # @api private
         #
-        def initialize
+        def initialize(file)
+          @file = file
           @source = nil
           @expected = []
         end
@@ -40,7 +41,7 @@ module Mutant
         #
         def example
           raise 'source not defined' unless @source
-          Example.new(@source, @expected)
+          Example.new(@file, @source, @expected)
         end
 
       private

lib/mutant/mutator/node/rescue.rb

@@ -34,8 +34,11 @@ module Mutant
         #
         def mutate_rescue_bodies
           children_indices(RESCUE_INDICES).each do |index|
-            next unless children.at(index)
+            rescue_body = children.at(index)
+            next unless rescue_body
             mutate_child(index)
+            resbody_body = AST::Meta.for(rescue_body).body
+            emit_concat(resbody_body) if resbody_body
           end
         end
 
@@ -48,8 +51,11 @@ module Mutant
         # @api private
         #
         def emit_concat(child)
-          raise unless body
-          emit(s(:begin, body, child))
+          if body
+            emit(s(:begin, body, child))
+          else
+            emit(child)
+          end
         end
 
         # Emit body mutations

meta/def.rb

@@ -14,7 +14,7 @@ Mutant::Meta::Example.add do
   mutation 'def foo; self; rescue; end'
   mutation 'def foo; end'
 
-  # Promote rescue body
+  # Promote rescue resbody bodies
   mutation 'def foo; foo; end'
 end
 
@@ -29,10 +29,13 @@ Mutant::Meta::Example.add do
   mutation 'def a; foo; rescue; bar; else; nil; end'
   mutation 'def a; foo; rescue; bar; else; self; end'
 
+  # Promote and concat rescue resbody bodies
+  mutation 'def a; foo; bar; end'
+
   # Promote and concat else body
   mutation 'def a; foo; baz; end'
 
-  # Promote body
+  # Promote rescue body
   mutation 'def a; foo; end'
 
   # Empty body

meta/rescue.rb

@@ -9,6 +9,8 @@ Mutant::Meta::Example.add do
   mutation 'begin; rescue ExceptionA, self => error; true; end'
   mutation 'begin; rescue ExceptionA, ExceptionB => error; false; end'
   mutation 'begin; rescue ExceptionA, ExceptionB => error; nil; end'
+  mutation 'begin; true; end'
+
 end
 
 Mutant::Meta::Example.add do
@@ -19,6 +21,7 @@ Mutant::Meta::Example.add do
   mutation 'begin; rescue SomeException => error; false; end'
   mutation 'begin; rescue SomeException => error; nil; end'
   mutation 'begin; rescue self => error; true; end'
+  mutation 'begin; true; end'
 end
 
 Mutant::Meta::Example.add do
@@ -28,6 +31,7 @@ Mutant::Meta::Example.add do
   mutation 'begin; rescue => error; false; end'
   mutation 'begin; rescue => error; nil; end'
   mutation 'begin; rescue; true; end'
+  mutation 'begin; true; end'
 end
 
 Mutant::Meta::Example.add do
@@ -36,4 +40,5 @@ Mutant::Meta::Example.add do
   singleton_mutations
   mutation 'begin; rescue; false; end'
   mutation 'begin; rescue; nil; end'
+  mutation 'begin; true end'
 end