Add properties lint

lib/pelusa/lint.rb

@@ -4,6 +4,7 @@
 require 'pelusa/lint/demeter_law'
 require 'pelusa/lint/indentation_level'
 require 'pelusa/lint/else_clauses'
+require 'pelusa/lint/properties'
 
 module Pelusa
   # Public: A Lint is a quality standard, applicable on a given piece of code to
@@ -17,6 +18,7 @@ def self.all
         DemeterLaw,
         IndentationLevel,
         ElseClauses,
+        Properties,
       ]
     end
   end

lib/pelusa/lint/properties.rb

@@ -0,0 +1,37 @@
+module Pelusa
+  module Lint
+    class Properties
+      def initialize
+        @violations = Set.new
+      end
+
+      def check(klass)
+        initialize
+        iterate_lines!(klass)
+
+        return SuccessfulAnalysis.new(name) if @violations.empty?
+
+        FailedAnalysis.new(name, @violations) do |violations|
+          "There are getters, setters or properties in lines #{violations.to_a.join(', ')}"
+        end
+      end
+
+      private
+
+      def name
+        "Doesn't use getters, setters or properties"
+      end
+
+      def iterate_lines!(klass)
+        iterator = Iterator.new do |node|
+          if node.is_a?(Rubinius::AST::Send)
+            if [:attr_accessor, :attr_writer, :attr_reader].include? node.name
+              @violations << node.line
+            end
+          end
+        end
+        Array(klass).each(&iterator)
+      end
+    end
+  end
+end

test/pelusa/lint/properties_test.rb

@@ -0,0 +1,44 @@
+require 'test_helper'
+
+module Pelusa
+  module Lint
+    describe Properties do
+      before do
+        @lint = Properties.new
+      end
+
+      describe '#check' do
+        describe 'when the class does not use getters, setters or properties' do
+          it 'returns a SuccessAnalysis' do
+            klass = """
+            class Foo
+              def initialize
+                @name = 'john'
+              end
+
+              def name
+                @name
+              end
+            end""".to_ast
+
+            analysis = @lint.check(klass)
+            analysis.successful?.must_equal true
+          end
+        end
+
+        describe 'when the class uses getters, setters or properties' do
+          it 'returns a FailureAnalysis' do
+            klass = """
+            class Foo
+              attr_accessor :name
+              attr_reader :foo
+            end""".to_ast
+
+            analysis = @lint.check(klass)
+            analysis.failed?.must_equal true
+          end
+        end
+      end
+    end
+  end
+end