From 3e527c5f998c022d628557c82e47407758837cfe Mon Sep 17 00:00:00 2001
From: Dmytro Lomako <felixfearest@gmail.com>
Date: Thu, 6 Jul 2023 01:19:08 +0300
Subject: [PATCH] added custom outputs binary state methods

---
 .byebug_history                          | 11 ++++++++
 .gitignore                               |  1 +
 lib/trailblazer/operation/public_call.rb |  2 +-
 lib/trailblazer/operation/railway.rb     | 14 +++++----
 test/custom_output_test.rb               | 36 ++++++++++++++++++++++++
 test/result_test.rb                      |  6 ++--
 6 files changed, 61 insertions(+), 9 deletions(-)
 create mode 100644 .byebug_history
 create mode 100644 test/custom_output_test.rb

diff --git a/.byebug_history b/.byebug_history
new file mode 100644
index 0000000..34347aa
--- /dev/null
+++ b/.byebug_history
@@ -0,0 +1,11 @@
+c
+success
+c
+event
+Result.new(Create,  {"x" => String}, event)
+success.inspect
+success
+c
+success.inspect
+quit
+success.inspect
diff --git a/.gitignore b/.gitignore
index cbb29a0..df9e0c1 100644
--- a/.gitignore
+++ b/.gitignore
@@ -16,3 +16,4 @@ test/version_tmp
 tmp
 /**/*.log
 .rubocop-*yml
+.idea
diff --git a/lib/trailblazer/operation/public_call.rb b/lib/trailblazer/operation/public_call.rb
index 8841f5a..6a775f8 100644
--- a/lib/trailblazer/operation/public_call.rb
+++ b/lib/trailblazer/operation/public_call.rb
@@ -46,7 +46,7 @@ def call_with_public_interface(options, flow_options, invoke_class: Activity::Ta
       )
 
       # Result is successful if the activity ended with an End event derived from Railway::End::Success.
-      Operation::Railway::Result(signal, ctx, flow_options)
+      Operation::Railway::Result(self, signal, ctx, flow_options)
     end
 
     # This interface is used for all nested OPs (and the outer-most, too).
diff --git a/lib/trailblazer/operation/railway.rb b/lib/trailblazer/operation/railway.rb
index 6dc9f5c..1959a96 100644
--- a/lib/trailblazer/operation/railway.rb
+++ b/lib/trailblazer/operation/railway.rb
@@ -11,16 +11,20 @@ def self.fail_fast!; Activity::FastTrack::FailFast end
       def self.pass_fast!; Activity::FastTrack::PassFast end
       # @param options Context
       # @param end_event The last emitted signal in a circuit is usually the end event.
-      def self.Result(end_event, options, *)
-        Result.new(end_event.kind_of?(End::Success), options, end_event)
+      def self.Result(activity, end_event, options, *)
+        Result.new(activity, options, end_event)
       end
 
       # The Railway::Result knows about its binary state, the context (data), and the last event in the circuit.
       class Result < Result # Operation::Result
-        def initialize(success, data, event)
-          super(success, data)
-
+        def initialize(activity, data, event)
+          super(event.kind_of?(End::Success), data)
           @event = event
+
+          # generate [:success?, :pass_fast?, :fail_fast?, :failure?, :<custom_output>?] methods
+          activity.to_h[:outputs].each do |output|
+            define_singleton_method("#{output[:semantic]}?") {  event.to_h[:semantic] == output[:semantic] }
+          end
         end
 
         attr_reader :event
diff --git a/test/custom_output_test.rb b/test/custom_output_test.rb
new file mode 100644
index 0000000..d3ee25e
--- /dev/null
+++ b/test/custom_output_test.rb
@@ -0,0 +1,36 @@
+require "test_helper"
+
+class CustomOutputTest < Minitest::Spec
+  # #success passes fast.
+  class Execute < Trailblazer::Operation
+    UsePaypal = Class.new(Trailblazer::Activity::Signal)
+
+    step :find_provider, Output(UsePaypal, :paypal) => End(:paypal)
+    step :charge_creditcard
+
+    def find_provider(ctx, params:, **)
+      return true unless params[:provider] == :paypal
+      UsePaypal
+    end
+
+    def charge_creditcard(ctx, **)
+      ctx[:charged] = true
+    end
+  end
+
+  describe "if a custom output is used in an operation" do
+    it "adds `<custom_output>?` method to the result object which returns true if the operation takes the correspondent track" do
+      result = Execute.(params: {provider: :paypal})
+      assert result.paypal?
+      assert !result.success?
+      assert !result.failure?
+      refute_respond_to result, :papa_johns?
+
+      result = Execute.(params: {provider: :not_paypal})
+      assert !result.paypal?
+      assert result.success?
+      assert !result.failure?
+    end
+  end
+
+end
diff --git a/test/result_test.rb b/test/result_test.rb
index 9df1fd0..62e49d2 100644
--- a/test/result_test.rb
+++ b/test/result_test.rb
@@ -4,8 +4,8 @@ class RailwayResultTest < Minitest::Spec
   Result  = Trailblazer::Operation::Railway::Result
   Success = Trailblazer::Operation::Railway::End::Success
 
-  let(:event)    { Success.new(semantic: nil) }
-  let(:success)  { Result.new(true, {"x" => String}, event) }
+  let(:event)    { Success.new(semantic: :success) }
+  let(:success)  { Result.new(Create,  {"x" => String}, event) }
 
   it { success.success?.must_equal true }
   it { success.failure?.must_equal false }
@@ -20,7 +20,7 @@ class RailwayResultTest < Minitest::Spec
   #---
   # inspect
   it { success.inspect.must_equal %{<Result:true {\"x\"=>String} >} }
-  it { Result.new(true, {"x" => true, "y" => 1, "z" => 2}, event).inspect("z", "y").must_equal %{<Result:true [2, 1] >} }
+  it { Result.new(Create, {"x" => true, "y" => 1, "z" => 2}, event).inspect("z", "y").must_equal %{<Result:true [2, 1] >} }
 
   class Create < Trailblazer::Operation
     pass :call