From bc0fbb605e31a3dea3c3588ec6af15a614ae931d Mon Sep 17 00:00:00 2001
From: Kasper Meyer <hi@kaspermeyer.com>
Date: Mon, 19 Oct 2020 20:17:02 +0200
Subject: [PATCH 1/3] Ensure interactors inherit hooks defined in ancestors

---
 README.md                     |  56 +++++++++++++
 lib/interactor/hooks.rb       | 151 ++++++++++++++++++++++++++++++++--
 spec/interactor/hooks_spec.rb | 104 +++++++++++++++++++++++
 3 files changed, 304 insertions(+), 7 deletions(-)

diff --git a/README.md b/README.md
index 6de00f2..30e5a70 100644
--- a/README.md
+++ b/README.md
@@ -470,6 +470,62 @@ end
 interactor should have a single purpose, there should be no need to clean up
 after any failed interactor.
 
+## Interactor Inheritance
+
+Interactors can inherit from other interactors. Subclasses will inherit hooks declared in ancestors:
+
+```ruby
+class ParentInteractor
+  around do |interactor|
+    puts "around before ancestor"
+    interactor.call
+    puts "around after ancestor"
+  end
+
+  before do
+    puts "before ancestor"
+  end
+
+  after do
+    puts "after ancestor"
+  end
+end
+
+class ChildInteractor < ParentInteractor
+  around do |interactor|
+    puts "around before child"
+    interactor.call
+    puts "around after child"
+  end
+
+  before do
+    puts "before child"
+  end
+
+  after do
+    puts "after child"
+  end
+
+  def call
+    puts "called"
+  end
+end
+```
+
+Calling the child interactor will output:
+
+```
+around before child
+around before parent
+before child
+before parent
+called
+after parent
+after child
+around after parent
+around after child
+```
+
 ## Testing Interactors
 
 When written correctly, an interactor is easy to test because it only *does* one
diff --git a/lib/interactor/hooks.rb b/lib/interactor/hooks.rb
index d82e7a5..3c2369a 100644
--- a/lib/interactor/hooks.rb
+++ b/lib/interactor/hooks.rb
@@ -50,7 +50,7 @@ module ClassMethods
       # Returns nothing.
       def around(*hooks, &block)
         hooks << block if block
-        hooks.each { |hook| around_hooks.push(hook) }
+        hooks.each { |hook| internal_around_hooks.push(hook) }
       end
 
       # Public: Declare hooks to run before Interactor invocation. The before
@@ -87,7 +87,7 @@ def around(*hooks, &block)
       # Returns nothing.
       def before(*hooks, &block)
         hooks << block if block
-        hooks.each { |hook| before_hooks.push(hook) }
+        hooks.each { |hook| internal_before_hooks.push(hook) }
       end
 
       # Public: Declare hooks to run after Interactor invocation. The after
@@ -124,11 +124,12 @@ def before(*hooks, &block)
       # Returns nothing.
       def after(*hooks, &block)
         hooks << block if block
-        hooks.each { |hook| after_hooks.unshift(hook) }
+        hooks.each { |hook| internal_after_hooks.unshift(hook) }
       end
 
       # Internal: An Array of declared hooks to run around Interactor
       # invocation. The hooks appear in the order in which they will be run.
+      # Includes hooks declared in ancestors.
       #
       # Examples
       #
@@ -143,11 +144,12 @@ def after(*hooks, &block)
       #
       # Returns an Array of Symbols and Procs.
       def around_hooks
-        @around_hooks ||= []
+        internal_around_hooks + ancestor_around_hooks
       end
 
       # Internal: An Array of declared hooks to run before Interactor
       # invocation. The hooks appear in the order in which they will be run.
+      # Includes hooks declared in ancestors.
       #
       # Examples
       #
@@ -162,11 +164,12 @@ def around_hooks
       #
       # Returns an Array of Symbols and Procs.
       def before_hooks
-        @before_hooks ||= []
+        internal_before_hooks + ancestor_before_hooks
       end
 
-      # Internal: An Array of declared hooks to run before Interactor
+      # Internal: An Array of declared hooks to run after Interactor
       # invocation. The hooks appear in the order in which they will be run.
+      # Includes hooks declared in ancestors.
       #
       # Examples
       #
@@ -181,7 +184,141 @@ def before_hooks
       #
       # Returns an Array of Symbols and Procs.
       def after_hooks
-        @after_hooks ||= []
+        ancestor_after_hooks + internal_after_hooks
+      end
+
+      # Internal: An Array of declared hooks to run around Interactor
+      # invocation. The hooks appear in the order in which they will be run.
+      #
+      # Examples
+      #
+      #   class MyInteractor
+      #     include Interactor
+      #
+      #     around :time_execution, :use_transaction
+      #   end
+      #
+      #   MyInteractor.internal_around_hooks
+      #   # => [:time_execution, :use_transaction]
+      #
+      # Returns an Array of Symbols and Procs.
+      def internal_around_hooks
+        @internal_around_hooks ||= []
+      end
+
+      # Internal: An Array of declared hooks to run before Interactor
+      # invocation. The hooks appear in the order in which they will be run.
+      #
+      # Examples
+      #
+      #   class MyInteractor
+      #     include Interactor
+      #
+      #     before :set_start_time, :say_hello
+      #   end
+      #
+      #   MyInteractor.internal_before_hooks
+      #   # => [:set_start_time, :say_hello]
+      #
+      # Returns an Array of Symbols and Procs.
+      def internal_before_hooks
+        @internal_before_hooks ||= []
+      end
+
+      # Internal: An Array of declared hooks to run after Interactor
+      # invocation. The hooks appear in the order in which they will be run.
+      #
+      # Examples
+      #
+      #   class MyInteractor
+      #     include Interactor
+      #
+      #     after :set_finish_time, :say_goodbye
+      #   end
+      #
+      #   MyInteractor.internal_after_hooks
+      #   # => [:say_goodbye, :set_finish_time]
+      #
+      # Returns an Array of Symbols and Procs.
+      def internal_after_hooks
+        @internal_after_hooks ||= []
+      end
+
+      # Internal: An Array of around hooks declared in ancestors.
+      # The hooks appear in the order in which they will be run.
+      #
+      # Examples
+      #
+      #   class MyParentInteractor
+      #     include Interactor
+      #
+      #     around :time_execution, :use_transaction
+      #   end
+      #
+      #   class MyChildInteractor < MyParentInteractor
+      #   end
+      #
+      #   MyChildInteractor.ancestor_around_hooks
+      #   # => [:time_execution, :use_transaction]
+      #
+      # Returns an Array of Symbols and Procs.
+      def ancestor_around_hooks
+        ancestor_hooks(:around_hooks)
+      end
+
+      # Internal: An Array of before hooks declared in ancestors.
+      # The hooks appear in the order in which they will be run.
+      #
+      # Examples
+      #
+      #   class MyParentInteractor
+      #     include Interactor
+      #
+      #     before :set_finish_time, :say_goodbye
+      #   end
+      #
+      #   class MyChildInteractor < MyParentInteractor
+      #   end
+      #
+      #   MyChildInteractor.ancestor_before_hooks
+      #   # => [:set_finish_time, :say_goodbye]
+      #
+      # Returns an Array of Symbols and Procs.
+      def ancestor_before_hooks
+        ancestor_hooks(:before_hooks)
+      end
+
+      # Internal: An Array of after hooks declared in ancestors.
+      # The hooks appear in the order in which they will be run.
+      #
+      # Examples
+      #
+      #   class MyParentInteractor
+      #     include Interactor
+      #
+      #     after :set_finish_time, :say_goodbye
+      #   end
+      #
+      #   class MyChildInteractor < MyParentInteractor
+      #   end
+      #
+      #   MyChildInteractor.ancestor_after_hooks
+      #   # => [:say_goodbye, :set_finish_time]
+      #
+      # Returns an Array of Symbols and Procs.
+      def ancestor_after_hooks
+        ancestor_hooks(:after_hooks)
+      end
+
+      private
+
+      # Internal: Fetches hooks declared in the ancestor.
+      #
+      # name - A Symbol corresponding to the hook method in the ancestor.
+      #
+      # Returns an Array of Symbols and Procs.
+      def ancestor_hooks(name)
+        superclass && superclass.respond_to?(name) ? superclass.send(name) : []
       end
     end
 
diff --git a/spec/interactor/hooks_spec.rb b/spec/interactor/hooks_spec.rb
index e0a188b..afc9ce6 100644
--- a/spec/interactor/hooks_spec.rb
+++ b/spec/interactor/hooks_spec.rb
@@ -353,6 +353,110 @@ def add_after2
           ])
         end
       end
+
+      context "with inheritance" do
+        context "with multiple ancestors" do
+          let(:ancestor_top) {
+            build_hooked do
+              around do |interactor|
+                steps << :around_before_ancestor_top
+                interactor.call
+                steps << :around_after_ancestor_top
+              end
+
+              before do
+                steps << :before_ancestor_top
+              end
+
+              after do
+                steps << :after_ancestor_top
+              end
+            end
+          }
+
+          let(:ancestor) {
+            Class.new(ancestor_top) do
+              around do |interactor|
+                steps << :around_before_ancestor
+                interactor.call
+                steps << :around_after_ancestor
+              end
+
+              before do
+                steps << :before_ancestor
+              end
+
+              after do
+                steps << :after_ancestor
+              end
+            end
+          }
+
+          let(:hooked) {
+            Class.new(ancestor) do
+              around do |interactor|
+                steps << :around_before
+                interactor.call
+                steps << :around_after
+              end
+
+              before do
+                steps << :before
+              end
+
+              after do
+                steps << :after
+              end
+            end
+          }
+
+          it "runs hooks defined in ancestors" do
+            expect(hooked.process).to eq([
+              :around_before,
+              :around_before_ancestor,
+              :around_before_ancestor_top,
+              :before,
+              :before_ancestor,
+              :before_ancestor_top,
+              :process,
+              :after_ancestor_top,
+              :after_ancestor,
+              :after,
+              :around_after_ancestor_top,
+              :around_after_ancestor,
+              :around_after
+            ])
+          end
+        end
+
+        describe "with hooks added to ancestors at runtime" do
+          let(:ancestor) {
+            build_hooked do
+              before do
+                steps << :before_at_parse
+              end
+            end
+          }
+
+          let(:hooked) {
+            Class.new(ancestor)
+          }
+
+          before do
+            ancestor.before do
+              steps << :before_at_runtime
+            end
+          end
+
+          it "runs hooks defined in ancestors" do
+            expect(hooked.process).to eq([
+              :before_at_parse,
+              :before_at_runtime,
+              :process
+            ])
+          end
+        end
+      end
     end
   end
 end

From c9ba0d3a9bea76136eb69504ab0e94426fa280e0 Mon Sep 17 00:00:00 2001
From: Kasper Meyer <hi@kaspermeyer.com>
Date: Sat, 31 Oct 2020 16:55:07 +0100
Subject: [PATCH 2/3] Fix Standard violations

---
 lib/interactor/hooks.rb       |  2 +-
 spec/integration_spec.rb      | 54 +++++++++++++++++------------------
 spec/interactor/hooks_spec.rb | 26 ++++++++---------
 spec/spec_helper.rb           |  2 +-
 4 files changed, 42 insertions(+), 42 deletions(-)

diff --git a/lib/interactor/hooks.rb b/lib/interactor/hooks.rb
index 3c2369a..45747e7 100644
--- a/lib/interactor/hooks.rb
+++ b/lib/interactor/hooks.rb
@@ -318,7 +318,7 @@ def ancestor_after_hooks
       #
       # Returns an Array of Symbols and Procs.
       def ancestor_hooks(name)
-        superclass && superclass.respond_to?(name) ? superclass.send(name) : []
+        superclass&.respond_to?(name) ? superclass.send(name) : []
       end
     end
 
diff --git a/spec/integration_spec.rb b/spec/integration_spec.rb
index ca083f3..be6217f 100644
--- a/spec/integration_spec.rb
+++ b/spec/integration_spec.rb
@@ -308,7 +308,7 @@ def rollback
         :around_before4c, :before4c, :call4c, :after4c, :around_after4c,
         :after4, :around_after4,
         :around_before5, :before5, :call5, :after5, :around_after5,
-        :after, :around_after,
+        :after, :around_after
       ])
     end
   end
@@ -406,7 +406,7 @@ def rollback
       }.to change {
         context.steps
       }.from([]).to([
-        :around_before,
+        :around_before
       ])
     end
   end
@@ -440,7 +440,7 @@ def rollback
       }.to change {
         context.steps
       }.from([]).to([
-        :around_before,
+        :around_before
       ])
     end
 
@@ -497,7 +497,7 @@ def rollback
         :rollback3,
         :rollback2c,
         :rollback2b,
-        :rollback2a,
+        :rollback2a
       ])
     end
   end
@@ -551,7 +551,7 @@ def rollback
         :rollback3,
         :rollback2c,
         :rollback2b,
-        :rollback2a,
+        :rollback2a
       ])
     end
 
@@ -609,7 +609,7 @@ def rollback
         :rollback3,
         :rollback2c,
         :rollback2b,
-        :rollback2a,
+        :rollback2a
       ])
     end
   end
@@ -664,7 +664,7 @@ def rollback
         :rollback3,
         :rollback2c,
         :rollback2b,
-        :rollback2a,
+        :rollback2a
       ])
     end
 
@@ -717,7 +717,7 @@ def rollback
         :after2, :around_after2,
         :rollback2c,
         :rollback2b,
-        :rollback2a,
+        :rollback2a
       ])
     end
   end
@@ -765,7 +765,7 @@ def rollback
         :after2, :around_after2,
         :rollback2c,
         :rollback2b,
-        :rollback2a,
+        :rollback2a
       ])
     end
 
@@ -819,7 +819,7 @@ def rollback
         :around_before3,
         :rollback2c,
         :rollback2b,
-        :rollback2a,
+        :rollback2a
       ])
     end
   end
@@ -870,7 +870,7 @@ def rollback
         :around_before3,
         :rollback2c,
         :rollback2b,
-        :rollback2a,
+        :rollback2a
       ])
     end
 
@@ -924,7 +924,7 @@ def rollback
         :around_before3, :before3,
         :rollback2c,
         :rollback2b,
-        :rollback2a,
+        :rollback2a
       ])
     end
   end
@@ -975,7 +975,7 @@ def rollback
         :around_before3, :before3,
         :rollback2c,
         :rollback2b,
-        :rollback2a,
+        :rollback2a
       ])
     end
 
@@ -1030,7 +1030,7 @@ def rollback
         :rollback3,
         :rollback2c,
         :rollback2b,
-        :rollback2a,
+        :rollback2a
       ])
     end
   end
@@ -1082,7 +1082,7 @@ def rollback
         :rollback3,
         :rollback2c,
         :rollback2b,
-        :rollback2a,
+        :rollback2a
       ])
     end
 
@@ -1137,7 +1137,7 @@ def rollback
         :rollback3,
         :rollback2c,
         :rollback2b,
-        :rollback2a,
+        :rollback2a
       ])
     end
   end
@@ -1189,7 +1189,7 @@ def rollback
         :rollback3,
         :rollback2c,
         :rollback2b,
-        :rollback2a,
+        :rollback2a
       ])
     end
 
@@ -1247,7 +1247,7 @@ def rollback
         :rollback3,
         :rollback2c,
         :rollback2b,
-        :rollback2a,
+        :rollback2a
       ])
     end
   end
@@ -1300,7 +1300,7 @@ def rollback
         :rollback3,
         :rollback2c,
         :rollback2b,
-        :rollback2a,
+        :rollback2a
       ])
     end
 
@@ -1359,7 +1359,7 @@ def rollback
         :rollback3,
         :rollback2c,
         :rollback2b,
-        :rollback2a,
+        :rollback2a
       ])
     end
   end
@@ -1415,7 +1415,7 @@ def rollback
         :rollback3,
         :rollback2c,
         :rollback2b,
-        :rollback2a,
+        :rollback2a
       ])
     end
 
@@ -1474,7 +1474,7 @@ def rollback
         :rollback3,
         :rollback2c,
         :rollback2b,
-        :rollback2a,
+        :rollback2a
       ])
     end
   end
@@ -1530,7 +1530,7 @@ def rollback
         :rollback3,
         :rollback2c,
         :rollback2b,
-        :rollback2a,
+        :rollback2a
       ])
     end
 
@@ -1590,7 +1590,7 @@ def rollback
         :rollback3,
         :rollback2c,
         :rollback2b,
-        :rollback2a,
+        :rollback2a
       ])
     end
   end
@@ -1647,7 +1647,7 @@ def rollback
         :rollback3,
         :rollback2c,
         :rollback2b,
-        :rollback2a,
+        :rollback2a
       ])
     end
 
@@ -1707,7 +1707,7 @@ def rollback
         :rollback3,
         :rollback2c,
         :rollback2b,
-        :rollback2a,
+        :rollback2a
       ])
     end
   end
@@ -1764,7 +1764,7 @@ def rollback
         :rollback3,
         :rollback2c,
         :rollback2b,
-        :rollback2a,
+        :rollback2a
       ])
     end
 
diff --git a/spec/interactor/hooks_spec.rb b/spec/interactor/hooks_spec.rb
index afc9ce6..0ce0782 100644
--- a/spec/interactor/hooks_spec.rb
+++ b/spec/interactor/hooks_spec.rb
@@ -43,7 +43,7 @@ def add_around_before_and_around_after(hooked)
           expect(hooked.process).to eq([
             :around_before,
             :process,
-            :around_after,
+            :around_after
           ])
         end
       end
@@ -63,7 +63,7 @@ def add_around_before_and_around_after(hooked)
           expect(hooked.process).to eq([
             :around_before,
             :process,
-            :around_after,
+            :around_after
           ])
         end
       end
@@ -93,7 +93,7 @@ def add_around_before1_and_around_after1(hooked)
             :around_before2,
             :process,
             :around_after2,
-            :around_after1,
+            :around_after1
           ])
         end
       end
@@ -125,7 +125,7 @@ def add_around_before2_and_around_after2(hooked)
             :around_before2,
             :process,
             :around_after2,
-            :around_after1,
+            :around_after1
           ])
         end
       end
@@ -146,7 +146,7 @@ def add_before
         it "runs the before hook method" do
           expect(hooked.process).to eq([
             :before,
-            :process,
+            :process
           ])
         end
       end
@@ -163,7 +163,7 @@ def add_before
         it "runs the before hook block" do
           expect(hooked.process).to eq([
             :before,
-            :process,
+            :process
           ])
         end
       end
@@ -187,7 +187,7 @@ def add_before1
           expect(hooked.process).to eq([
             :before1,
             :before2,
-            :process,
+            :process
           ])
         end
       end
@@ -213,7 +213,7 @@ def add_before2
           expect(hooked.process).to eq([
             :before1,
             :before2,
-            :process,
+            :process
           ])
         end
       end
@@ -234,7 +234,7 @@ def add_after
         it "runs the after hook method" do
           expect(hooked.process).to eq([
             :process,
-            :after,
+            :after
           ])
         end
       end
@@ -251,7 +251,7 @@ def add_after
         it "runs the after hook block" do
           expect(hooked.process).to eq([
             :process,
-            :after,
+            :after
           ])
         end
       end
@@ -275,7 +275,7 @@ def add_after1
           expect(hooked.process).to eq([
             :process,
             :after2,
-            :after1,
+            :after1
           ])
         end
       end
@@ -301,7 +301,7 @@ def add_after2
           expect(hooked.process).to eq([
             :process,
             :after2,
-            :after1,
+            :after1
           ])
         end
       end
@@ -349,7 +349,7 @@ def add_after2
             :after2,
             :after1,
             :around_after2,
-            :around_after1,
+            :around_after1
           ])
         end
       end
diff --git a/spec/spec_helper.rb b/spec/spec_helper.rb
index ead3a1c..8a6db02 100644
--- a/spec/spec_helper.rb
+++ b/spec/spec_helper.rb
@@ -5,4 +5,4 @@
 
 require "interactor"
 
-Dir[File.expand_path("../support/*.rb", __FILE__)].each { |f| require f }
+Dir[File.expand_path("../support/*.rb", __FILE__)].sort.each { |f| require f }

From 21bffd91474002864f51dffeaec7c1e4f8ba2143 Mon Sep 17 00:00:00 2001
From: Kasper Meyer <hi@kaspermeyer.com>
Date: Sat, 31 Oct 2020 17:39:18 +0100
Subject: [PATCH 3/3] Slim down method footprint

---
 lib/interactor/hooks.rb | 80 ++++-------------------------------------
 1 file changed, 7 insertions(+), 73 deletions(-)

diff --git a/lib/interactor/hooks.rb b/lib/interactor/hooks.rb
index 45747e7..353d531 100644
--- a/lib/interactor/hooks.rb
+++ b/lib/interactor/hooks.rb
@@ -144,7 +144,7 @@ def after(*hooks, &block)
       #
       # Returns an Array of Symbols and Procs.
       def around_hooks
-        internal_around_hooks + ancestor_around_hooks
+        internal_around_hooks + ancestor_hooks(:around_hooks)
       end
 
       # Internal: An Array of declared hooks to run before Interactor
@@ -164,7 +164,7 @@ def around_hooks
       #
       # Returns an Array of Symbols and Procs.
       def before_hooks
-        internal_before_hooks + ancestor_before_hooks
+        internal_before_hooks + ancestor_hooks(:before_hooks)
       end
 
       # Internal: An Array of declared hooks to run after Interactor
@@ -184,9 +184,11 @@ def before_hooks
       #
       # Returns an Array of Symbols and Procs.
       def after_hooks
-        ancestor_after_hooks + internal_after_hooks
+        ancestor_hooks(:after_hooks) + internal_after_hooks
       end
 
+      private
+
       # Internal: An Array of declared hooks to run around Interactor
       # invocation. The hooks appear in the order in which they will be run.
       #
@@ -244,81 +246,13 @@ def internal_after_hooks
         @internal_after_hooks ||= []
       end
 
-      # Internal: An Array of around hooks declared in ancestors.
-      # The hooks appear in the order in which they will be run.
-      #
-      # Examples
-      #
-      #   class MyParentInteractor
-      #     include Interactor
-      #
-      #     around :time_execution, :use_transaction
-      #   end
-      #
-      #   class MyChildInteractor < MyParentInteractor
-      #   end
-      #
-      #   MyChildInteractor.ancestor_around_hooks
-      #   # => [:time_execution, :use_transaction]
-      #
-      # Returns an Array of Symbols and Procs.
-      def ancestor_around_hooks
-        ancestor_hooks(:around_hooks)
-      end
-
-      # Internal: An Array of before hooks declared in ancestors.
-      # The hooks appear in the order in which they will be run.
-      #
-      # Examples
-      #
-      #   class MyParentInteractor
-      #     include Interactor
-      #
-      #     before :set_finish_time, :say_goodbye
-      #   end
-      #
-      #   class MyChildInteractor < MyParentInteractor
-      #   end
-      #
-      #   MyChildInteractor.ancestor_before_hooks
-      #   # => [:set_finish_time, :say_goodbye]
-      #
-      # Returns an Array of Symbols and Procs.
-      def ancestor_before_hooks
-        ancestor_hooks(:before_hooks)
-      end
-
-      # Internal: An Array of after hooks declared in ancestors.
-      # The hooks appear in the order in which they will be run.
-      #
-      # Examples
-      #
-      #   class MyParentInteractor
-      #     include Interactor
-      #
-      #     after :set_finish_time, :say_goodbye
-      #   end
-      #
-      #   class MyChildInteractor < MyParentInteractor
-      #   end
-      #
-      #   MyChildInteractor.ancestor_after_hooks
-      #   # => [:say_goodbye, :set_finish_time]
-      #
-      # Returns an Array of Symbols and Procs.
-      def ancestor_after_hooks
-        ancestor_hooks(:after_hooks)
-      end
-
-      private
-
       # Internal: Fetches hooks declared in the ancestor.
       #
       # name - A Symbol corresponding to the hook method in the ancestor.
       #
       # Returns an Array of Symbols and Procs.
-      def ancestor_hooks(name)
-        superclass&.respond_to?(name) ? superclass.send(name) : []
+      def ancestor_hooks(hook)
+        superclass&.respond_to?(hook) ? superclass.send(hook) : []
       end
     end