Add integration specs for deferred helpers.

lib/rspec/sleeping_king_studios/deferred/dsl.rb

@@ -4,7 +4,18 @@
 
 module RSpec::SleepingKingStudios::Deferred
   # Domain-specific language for defining deferred examples.
-  module Dsl; end
+  module Dsl
+    # Callback invoked when the module is extended into another module or class.
+    #
+    # Delegates to child module #extended methods.
+    #
+    # @param other [Module] the other module or class.
+    def self.extended(other)
+      super
+
+      other.extend(RSpec::SleepingKingStudios::Deferred::Dsl::MemoizedHelpers)
+    end
+  end
 end
 
 require 'rspec/sleeping_king_studios/deferred/dsl/examples'

lib/rspec/sleeping_king_studios/deferred/dsl/memoized_helpers.rb

@@ -2,7 +2,7 @@
 
 require 'rspec/sleeping_king_studios/deferred/dsl'
 
-module RSpec::SleepingKingStudios::Deferred::Dsl
+module RSpec::SleepingKingStudios::Deferred::Dsl # rubocop:disable Style/Documentation
   # DSL for defining memoized helpers for deferred examples.
   module MemoizedHelpers
     # Callback invoked when the module is extended into another module or class.
@@ -94,4 +94,6 @@ def subject!(helper_name = nil, &)
       before(:example) { send(helper_name) }
     end
   end
+
+  include MemoizedHelpers
 end

spec/integration/deferred/helpers_spec.fixture.rb

@@ -0,0 +1,9 @@
+# frozen_string_literal: true
+
+require 'support/integration/deferred/payload_examples'
+
+RSpec.describe Spec::Models::Rocket do
+  subject(:rocket) { described_class.new('Imp IV') }
+
+  include Spec::Integration::Deferred::PayloadExamples
+end

spec/integration/deferred/helpers_spec.rb

@@ -0,0 +1,28 @@
+# frozen_string_literal: true
+
+require 'rspec/sleeping_king_studios/deferred/examples'
+
+require 'support/sandbox'
+
+RSpec.describe RSpec::SleepingKingStudios::Deferred::Examples do
+  let(:fixture_file) do
+    %w[spec/integration/deferred/helpers_spec.fixture.rb]
+  end
+  let(:result) do
+    Spec::Support::Sandbox.run(fixture_file)
+  end
+  let(:expected_examples) do
+    <<~EXAMPLES.lines.map(&:strip)
+      Spec::Models::Rocket#launch when the rocket has a basic payload should not change the previous payload
+      Spec::Models::Rocket#launch when the rocket has a basic payload should set the payload
+      Spec::Models::Rocket#launch when the rocket has a complex payload should set the payload
+      Spec::Models::Rocket#payload is expected to be == {}
+    EXAMPLES
+  end
+
+  it 'should apply the deferred examples', :aggregate_failures do
+    expect(result.summary).to be == '4 examples, 0 failures'
+
+    expect(result.example_descriptions).to be == expected_examples
+  end
+end

spec/rspec/sleeping_king_studios/deferred/dsl/memoized_helpers_spec.rb

@@ -3,8 +3,6 @@
 require 'rspec/sleeping_king_studios/concerns/example_constants'
 require 'rspec/sleeping_king_studios/deferred/dsl/hooks'
 require 'rspec/sleeping_king_studios/deferred/dsl/memoized_helpers'
-require 'rspec/sleeping_king_studios/matchers/built_in/respond_to'
-require 'rspec/sleeping_king_studios/matchers/core/have_constant'
 
 require 'support/isolated_example_group'
 

spec/rspec/sleeping_king_studios/deferred/dsl_spec.rb

@@ -35,4 +35,6 @@
   include_examples 'should define deferred example groups'
 
   include_examples 'should define deferred hooks'
+
+  include_examples 'should define memoized helpers'
 end

spec/rspec/sleeping_king_studios/deferred/examples_spec.rb

@@ -35,4 +35,6 @@
   include_examples 'should define deferred example groups'
 
   include_examples 'should define deferred hooks'
+
+  include_examples 'should define memoized helpers'
 end

spec/support/integration/deferred/payload_examples.rb

@@ -0,0 +1,81 @@
+# frozen_string_literal: true
+
+require 'support/integration/deferred'
+
+module Spec::Integration::Deferred
+  module ShouldNotChangeThePreviousPayload
+    include RSpec::SleepingKingStudios::Deferred::Examples
+
+    let!(:previous_payload) { subject.payload }
+
+    it 'should not change the previous payload' do
+      launch_rocket(payload:)
+
+      expect(previous_payload).to be == {}
+    end
+  end
+
+  module WhenThePayloadIncludesABattery
+    include RSpec::SleepingKingStudios::Deferred::Examples
+
+    let(:payload) { super().merge(battery: true) }
+  end
+
+  module WhenThePayloadIncludesASolarArray
+    include RSpec::SleepingKingStudios::Deferred::Examples
+
+    let(:payload) { super().merge(solar_array: true) }
+  end
+
+  module WhenThePayloadIncludesExperiments
+    include RSpec::SleepingKingStudios::Deferred::Examples
+
+    let(:payload) { super().merge(experiments: true) }
+  end
+
+  module PayloadExamples
+    include RSpec::SleepingKingStudios::Deferred::Examples
+
+    describe '#launch' do
+      let(:launch_site) { 'KSC' }
+      let(:payload)     { {} }
+
+      def launch_rocket(**options)
+        subject.launch(launch_site:, **options)
+      end
+
+      context 'when the rocket has a basic payload' do
+        include Spec::Integration::Deferred::WhenThePayloadIncludesABattery
+        include Spec::Integration::Deferred::ShouldNotChangeThePreviousPayload
+
+        let(:expected) { { battery: true } }
+
+        it 'should set the payload' do
+          expect { launch_rocket(payload:) }
+            .to change(rocket, :payload)
+            .to be == expected
+        end
+      end
+
+      context 'when the rocket has a complex payload' do
+        include Spec::Integration::Deferred::WhenThePayloadIncludesABattery
+        include Spec::Integration::Deferred::WhenThePayloadIncludesASolarArray
+        include Spec::Integration::Deferred::WhenThePayloadIncludesExperiments
+
+        let(:expected) do
+          { battery: true, experiments: true, solar_array: true }
+        end
+
+        it 'should set the payload' do
+          expect { launch_rocket(payload:) }
+            .to change(rocket, :payload)
+            .to be == expected
+        end
+      end
+    end
+
+    describe '#payload' do
+      it { expect(subject.payload).to be == {} }
+    end
+  end
+end

spec/support/models/rocket.rb

@@ -19,14 +19,14 @@ def initialize(name)
 
         @launched    = false
         @launch_site = nil
-        @payload     = []
+        @payload     = {}
       end
 
       attr_reader \
         :launch_site,
         :payload
 
-      def launch(launch_site:, payload: [])
+      def launch(launch_site:, payload: {})
         @launched    = true
         @launch_site = launch_site
         @payload     = payload

spec/support/shared_examples/deferred_examples.rb

@@ -2,6 +2,7 @@
 
 require 'rspec/sleeping_king_studios/concerns/shared_example_group'
 require 'rspec/sleeping_king_studios/matchers/built_in/respond_to'
+require 'rspec/sleeping_king_studios/matchers/core/have_constant'
 
 require 'support/isolated_example_group'
 require 'support/shared_examples'