push up calculate method to base class.

4 files changed, 6 insertions, 13 deletions

diff --git a/lib/mathy/game.rb b/lib/mathy/game.rb
index 2b4441e..a9f8b24 100644
--- a/lib/mathy/game.rb
+++ b/lib/mathy/game.rb
@@ -6,7 +6,8 @@ module Mathy
     end
 
     def play(console)
-      console.display_results(@player, @score, play_turns(console))
+      turns_played = play_turns(console)
+      console.display_results(@player, @score, turns_played)
     end
 
     private
diff --git a/lib/mathy/operations/addition.rb b/lib/mathy/operations/addition.rb
index 615359c..a9c38ae 100644
--- a/lib/mathy/operations/addition.rb
+++ b/lib/mathy/operations/addition.rb
@@ -4,12 +4,6 @@ module Mathy
       def initialize(difficulty)
         super(difficulty, "+")
       end
-
-      def calculate(operands)
-        operands.inject do |result, x|
-          result + x
-        end
-      end
     end
   end
 end
diff --git a/lib/mathy/operations/operation.rb b/lib/mathy/operations/operation.rb
index ed8774a..ba6a16d 100644
--- a/lib/mathy/operations/operation.rb
+++ b/lib/mathy/operations/operation.rb
@@ -17,6 +17,10 @@ module Mathy
       def matches?(other_key)
         key == other_key
       end
+
+      def calculate(operands)
+        operands.inject { |result, x| result.send(key.to_sym, x) }
+      end
     end
   end
 end
diff --git a/lib/mathy/operations/subtraction.rb b/lib/mathy/operations/subtraction.rb
index 38b8ae6..72a7426 100644
--- a/lib/mathy/operations/subtraction.rb
+++ b/lib/mathy/operations/subtraction.rb
@@ -4,12 +4,6 @@ module Mathy
       def initialize(difficulty)
         super(difficulty, "-")
       end
-
-      def calculate(operands)
-        operands.inject do |result, x|
-          result - x
-        end
-      end
     end
   end
 end