Fix memoization for array settings

lib/cocoapods/target/build_settings.rb

@@ -98,15 +98,17 @@ module Pod
         dup_before_freeze = frozen && (from_pod_targets_to_link || from_search_paths_aggregate_targets || uniqued || sorted)
 
         define_method(method_name) do
-          retval =
           if memoized
             @__memoized ||= {}
-              @__memoized.fetch(memoized_key) { @__memoized[memoized_key] = send(raw_method_name) }
-            else
-              send(raw_method_name)
+            retval = @__memoized.fetch(memoized_key, :not_found)
+            return retval if :not_found != retval
           end
 
-          return if retval.nil?
+          retval = send(raw_method_name)
+          if retval.nil?
+            @__memoized[memoized_key] = retval if memoized
+            return
+          end
 
           retval = retval.dup if dup_before_freeze && retval.frozen?
 
@@ -118,6 +120,8 @@ module Pod
           retval.sort! if sorted
           retval.freeze if frozen
 
+          @__memoized[memoized_key] = retval if memoized
+
           retval
         end
       end

spec/unit/target/build_settings_spec.rb

@@ -11,6 +11,37 @@ module Pod
         BuildSettings::Aggregate.new(aggregate_target, configuration_name)
       end
 
+      describe 'memoization' do
+        it 'memoizes methods when requested' do
+          cls = Class.new(BuildSettings) do
+            define_build_settings_method :foobar, :memoized => true do
+              Object.new
+            end
+          end
+
+          settings = cls.new(stub('Target'))
+
+          object = settings.foobar
+          object.should.be.frozen
+          object.should.equal?(settings.foobar)
+        end
+
+        it 'memoizes array methods when requested' do
+          cls = Class.new(BuildSettings) do
+            define_build_settings_method :foobar, :memoized => true, :sorted => true, :uniqued => true do
+              %w(b a c a)
+            end
+          end
+
+          settings = cls.new(stub('Target'))
+
+          object = settings.foobar
+          object.should.be.frozen
+          object.should == %w(a b c)
+          object.should.equal?(settings.foobar)
+        end
+      end
+
       #---------------------------------------------------------------------#
 
       describe '::add_developers_frameworks_if_needed' do