From a9677a03868aa124604151b706c027ec67efd472 Mon Sep 17 00:00:00 2001
From: Guilherme Andrade <guilherme.andrade.ao@gmail.com>
Date: Mon, 9 Jan 2023 18:43:02 +0100
Subject: [PATCH] Allow use cases to work with do notation

---
 Gemfile.lock                                  |  2 +-
 lib/use_cases/module_optins/validated.rb      |  1 +
 lib/use_cases/result.rb                       | 14 ++++++++--
 lib/use_cases/version.rb                      |  2 +-
 .../operation_calling_use_case.rb             | 27 +++++++++++++++++++
 spec/use_cases/result_spec.rb                 | 16 +++++++++++
 6 files changed, 58 insertions(+), 4 deletions(-)
 create mode 100644 spec/support/test_subjects/operation_calling_use_case.rb
 create mode 100644 spec/use_cases/result_spec.rb

diff --git a/Gemfile.lock b/Gemfile.lock
index c9450a5..b2b1051 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -1,7 +1,7 @@
 PATH
   remote: .
   specs:
-    use_cases (3.0.0)
+    use_cases (3.0.1)
       activesupport (>= 6.1.7)
       dry-matcher (>= 0.8.1)
       dry-monads (>= 1.0.0)
diff --git a/lib/use_cases/module_optins/validated.rb b/lib/use_cases/module_optins/validated.rb
index 3258c9b..b793ae7 100644
--- a/lib/use_cases/module_optins/validated.rb
+++ b/lib/use_cases/module_optins/validated.rb
@@ -1,5 +1,6 @@
 # frozen_string_literal: true
 
+require "dry/validation"
 require "dry/validation/contract"
 
 module UseCases
diff --git a/lib/use_cases/result.rb b/lib/use_cases/result.rb
index 6fe1dde..e614d30 100644
--- a/lib/use_cases/result.rb
+++ b/lib/use_cases/result.rb
@@ -10,9 +10,19 @@ def initialize(step, result)
       @result = result
     end
 
+    def method_missing(method, *args, &block)
+      return result.send(method, *args, &block) if result.respond_to?(method)
+
+      super
+    end
+
+    def respond_to_missing?(method, include_private = false)
+      result.respond_to?(method, include_private) || super
+    end
+
     def value
       return result if result_not_monad?
-      return nil if result_empty?
+      return if result_empty?
 
       result.success? ? result.value! : result.failure
     end
@@ -39,7 +49,7 @@ def nil?
     end
 
     def to_result
-      self
+      result
     end
 
     def result_empty?
diff --git a/lib/use_cases/version.rb b/lib/use_cases/version.rb
index 0f5d439..76cb97a 100644
--- a/lib/use_cases/version.rb
+++ b/lib/use_cases/version.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
 
 module UseCases
-  VERSION = "3.0.1"
+  VERSION = "3.0.2"
 end
diff --git a/spec/support/test_subjects/operation_calling_use_case.rb b/spec/support/test_subjects/operation_calling_use_case.rb
new file mode 100644
index 0000000..b197e71
--- /dev/null
+++ b/spec/support/test_subjects/operation_calling_use_case.rb
@@ -0,0 +1,27 @@
+class OperationCallingUseCase
+  include Dry::Monads[:result]
+  include Dry::Monads::Do.for(:call)
+
+  def call
+    result = yield call_operation
+    Success(result)
+  end
+
+  private
+
+  def call_operation
+    operation = Operation.new
+    operation.call({})
+  end
+end
+
+# Path: spec/use_cases/steps/operation.rb
+class Operation
+  include UseCase
+
+  step :step_1
+
+  def step_1
+    Success(:step_1)
+  end
+end
diff --git a/spec/use_cases/result_spec.rb b/spec/use_cases/result_spec.rb
new file mode 100644
index 0000000..d9a6f5c
--- /dev/null
+++ b/spec/use_cases/result_spec.rb
@@ -0,0 +1,16 @@
+require 'spec_helper'
+
+RSpec.describe UseCases::Result do
+  describe 'self' do
+    context 'when used by a service using the do notation' do
+      let(:caller) do
+        require 'support/test_subjects/operation_calling_use_case'
+        OperationCallingUseCase.new
+      end
+
+      it 'works' do
+        expect(caller.call).to be_success
+      end
+    end
+  end
+end