lib/fluxo/result.rb in fluxo-0.2.1 vs lib/fluxo/result.rb in fluxo-0.3.0

@@ -1,10 +1,11 @@
 # frozen_string_literal: true
 
 module Fluxo
   class Result
-    attr_reader :operation, :type, :value, :ids
+    ATTRIBUTES = %i[operation type value ids transient_attributes].freeze
+    attr_reader(*ATTRIBUTES)
 
     # @param options [Hash]
     # @option options [Fluxo::Operation] :operation The operation instance that gererated this result
     # @option options [symbol] :type The type of the result. Allowed types: :ok, :failure, :exception
     # @option options [Any] :value The value of the result.
@@ -12,13 +13,17 @@
     def initialize(operation:, type:, value:, ids: nil)
       @operation = operation
       @value = value
       @type = type
       @ids = Array(ids)
+      @transient_attributes = {}
     end
 
     def mutate(**attrs)
-      self.class.new(**{operation: operation, type: type, value: value, ids: ids}.merge(attrs))
+      attrs.each do |key, value|
+        instance_variable_set("@#{key}", value) if ATTRIBUTES.include?(key)
+      end
+      self
     end
 
     def ==(other)
       other.is_a?(self.class) && other.operation == operation && other.type == type && other.value == value && other.ids == ids
     end