case.rb in u-case-2.2.0

- old
+ new

@@ -40,39 +40,61 @@
       instance = new(arg)
       instance.__set_result__(result)
       instance
     end
 
-    def self.__get_flow__
+    def self.__call!
+      return const_get(:Flow_Step) if const_defined?(:Flow_Step)
+
+      const_set(:Flow_Step, Class.new(self) do
+        private def __call
+          __call_use_case
+        end
+      end)
+    end
+
+    def self.call!
+      self
+    end
+
+    def self.__flow_reducer
+      Flow::Reducer
+    end
+
+    def self.__flow_get
       @__flow
     end
 
-    private_class_method def self.__set_flow__(reducer, args)
-      def self.use_cases; __get_flow__.use_cases; end
+    private_class_method def self.__flow_use_cases_set(args)
+      @__flow_use_cases = args
+    end
 
+    private_class_method def self.__flow_use_cases_get
+      Array(@__flow_use_cases)
+        .map { |use_case| use_case == self ? self.__call! : use_case }
+    end
+
+    private_class_method def self.__flow_set(args)
+      return if __flow_get
+
+      def self.use_cases; __flow_get.use_cases; end
+
       self.class_eval('def use_cases; self.class.use_cases; end')
 
-      reducer.build(args)
+      @__flow = __flow_reducer.build(args)
     end
 
-    def self.flow(*args)
-      @__flow ||= __set_flow__(Flow::Reducer, args)
+    def self.__flow_set!
+      __flow_set(__flow_use_cases_get) if !__flow_get && @__flow_use_cases
     end
 
-    def self.call!
-      return const_get(:Flow_Step) if const_defined?(:Flow_Step)
-
-      const_set(:Flow_Step, Class.new(self) do
-        private def __call
-          __call_use_case
-        end
-      end)
+    def self.flow(*args)
+      __flow_use_cases_set(args)
     end
 
     def initialize(input)
-      @__input = input
-      self.attributes = input
+      __setup_use_case(input)
     end
 
     def call!
       raise NotImplementedError
     end
@@ -88,21 +110,37 @@
       @__result = result
     end
 
     private
 
+      def __setup_use_case(input)
+        self.class.__flow_set!
+
+        @__input = input
+
+        self.attributes = input
+      end
+
       def __call
-        return self.class.__get_flow__.call(@__input) if self.class.__get_flow__
+        return __call_use_case_flow if __call_use_case_flow?
 
         __call_use_case
       end
 
       def __call_use_case
         result = call!
 
         return result if result.is_a?(Result)
 
         raise Error::UnexpectedResult.new(self.class)
+      end
+
+      def __call_use_case_flow?
+        self.class.__flow_get
+      end
+
+      def __call_use_case_flow
+        self.class.__flow_get.call(@__input)
       end
 
       def Success(arg = :ok)
         value, type = block_given? ? [yield, arg] : [arg, :ok]
 