Don't load AR integration if it is unavailable

.gitignore

@@ -5,6 +5,7 @@ gemfiles/*.gemfile.lock
 node_modules
 pkg
 spec/examples.txt
+spec/internal
 tmp
 zeus.server.log
 zeus.server-start.log

Appraisals

@@ -3,31 +3,29 @@ rails_dependencies =
     gem "activerecord-jdbcsqlite3-adapter", platform: :jruby
     gem "jdbc-sqlite3", platform: :jruby
     gem "net-ftp"
+    gem "combustion"
   end
 
 appraisals = {
   rails_6_0:
     proc do
       instance_eval(&rails_dependencies)
 
-      gem "activerecord", "~> 6.0.0"
-      gem "railties", "~> 6.0.0"
+      gem "rails", "~> 6.0.0"
       gem "sqlite3", "~> 1.4.0", platform: %i[ruby mswin mingw]
     end,
   rails_6_1:
     proc do
       instance_eval(&rails_dependencies)
 
-      gem "activerecord", "~> 6.1.0"
-      gem "railties", "~> 6.1.0"
+      gem "rails", "~> 6.1.0"
       gem "sqlite3", "~> 1.4.0", platform: %i[ruby mswin mingw]
     end,
   rails_7_0:
     proc do
       instance_eval(&rails_dependencies)
 
-      gem "activerecord", "~> 7.0.0"
-      gem "railties", "~> 7.0.0"
+      gem "rails", "~> 7.0.0"
       gem "sqlite3", "~> 1.4.0", platform: %i[ruby mswin mingw]
     end,
   no_rails: proc {},

gemfiles/rails_6_0_rspec_gte_3_10.gemfile

@@ -17,8 +17,8 @@ gem "warnings_logger"
 gem "activerecord-jdbcsqlite3-adapter", platform: :jruby
 gem "jdbc-sqlite3", platform: :jruby
 gem "net-ftp"
-gem "activerecord", "~> 6.0.0"
-gem "railties", "~> 6.0.0"
+gem "combustion"
+gem "rails", "~> 6.0.0"
 gem "sqlite3", "~> 1.4.0", platform: [:ruby, :mswin, :mingw]
 gem "rspec", ">= 3.10", "< 4"
 gem "rspec-rails"

gemfiles/rails_6_0_rspec_lt_3_10.gemfile

@@ -17,8 +17,8 @@ gem "warnings_logger"
 gem "activerecord-jdbcsqlite3-adapter", platform: :jruby
 gem "jdbc-sqlite3", platform: :jruby
 gem "net-ftp"
-gem "activerecord", "~> 6.0.0"
-gem "railties", "~> 6.0.0"
+gem "combustion"
+gem "rails", "~> 6.0.0"
 gem "sqlite3", "~> 1.4.0", platform: [:ruby, :mswin, :mingw]
 gem "rspec", "~> 3.9.0"
 gem "rspec-rails"

gemfiles/rails_6_1_rspec_gte_3_10.gemfile

@@ -17,8 +17,8 @@ gem "warnings_logger"
 gem "activerecord-jdbcsqlite3-adapter", platform: :jruby
 gem "jdbc-sqlite3", platform: :jruby
 gem "net-ftp"
-gem "activerecord", "~> 6.1.0"
-gem "railties", "~> 6.1.0"
+gem "combustion"
+gem "rails", "~> 6.1.0"
 gem "sqlite3", "~> 1.4.0", platform: [:ruby, :mswin, :mingw]
 gem "rspec", ">= 3.10", "< 4"
 gem "rspec-rails"

gemfiles/rails_6_1_rspec_lt_3_10.gemfile

@@ -17,8 +17,8 @@ gem "warnings_logger"
 gem "activerecord-jdbcsqlite3-adapter", platform: :jruby
 gem "jdbc-sqlite3", platform: :jruby
 gem "net-ftp"
-gem "activerecord", "~> 6.1.0"
-gem "railties", "~> 6.1.0"
+gem "combustion"
+gem "rails", "~> 6.1.0"
 gem "sqlite3", "~> 1.4.0", platform: [:ruby, :mswin, :mingw]
 gem "rspec", "~> 3.9.0"
 gem "rspec-rails"

gemfiles/rails_7_0_rspec_gte_3_10.gemfile

@@ -17,8 +17,8 @@ gem "warnings_logger"
 gem "activerecord-jdbcsqlite3-adapter", platform: :jruby
 gem "jdbc-sqlite3", platform: :jruby
 gem "net-ftp"
-gem "activerecord", "~> 7.0.0"
-gem "railties", "~> 7.0.0"
+gem "combustion"
+gem "rails", "~> 7.0.0"
 gem "sqlite3", "~> 1.4.0", platform: [:ruby, :mswin, :mingw]
 gem "rspec", ">= 3.10", "< 4"
 gem "rspec-rails"

gemfiles/rails_7_0_rspec_lt_3_10.gemfile

@@ -17,8 +17,8 @@ gem "warnings_logger"
 gem "activerecord-jdbcsqlite3-adapter", platform: :jruby
 gem "jdbc-sqlite3", platform: :jruby
 gem "net-ftp"
-gem "activerecord", "~> 7.0.0"
-gem "railties", "~> 7.0.0"
+gem "combustion"
+gem "rails", "~> 7.0.0"
 gem "sqlite3", "~> 1.4.0", platform: [:ruby, :mswin, :mingw]
 gem "rspec", "~> 3.9.0"
 gem "rspec-rails"

lib/super_diff/rails.rb

@@ -1 +1,2 @@
-require "super_diff/active_record"
+require "super_diff/active_support"
+require "super_diff/active_record" if defined?(ActiveRecord)

spec/integration/rails/engines_spec.rb

@@ -0,0 +1,20 @@
+require "spec_helper"
+
+RSpec.describe "Integration with Rails engines", type: :integration do
+  context "when ActiveRecord is not loaded via Combustion" do
+    it "does not fail to load" do
+      as_both_colored_and_uncolored do |color_enabled|
+        program =
+          make_rspec_rails_engine_program(
+            "expect(true).to be(true)",
+            combustion_initialize: [:action_controller],
+            color_enabled: color_enabled
+          )
+
+        expect(program).not_to produce_output_when_run(
+          "uninitialized constant ActiveRecord"
+        ).in_color(color_enabled)
+      end
+    end
+  end
+end

spec/support/integration/helpers.rb

@@ -32,6 +32,18 @@ def make_rspec_rails_test_program(test, color_enabled:)
       TestPrograms::RSpecRails.new(test, color_enabled: color_enabled)
     end
 
+    def make_rspec_rails_engine_program(
+      test,
+      color_enabled:,
+      combustion_initialize:
+    )
+      TestPrograms::RspecRailsEngine.new(
+        test,
+        color_enabled: color_enabled,
+        combustion_initialize: combustion_initialize
+      )
+    end
+
     def build_expected_output(
       color_enabled:,
       snippet:,

spec/support/integration/matchers/produce_output_when_run_matcher.rb

@@ -55,6 +55,12 @@ def failure_message
         end
       end
 
+      def failure_message_when_negated
+        "Expected output of test not to produce output, but it did.\n\n" +
+          "Actual output:\n\n" +
+          SuperDiff::Test::OutputHelpers.bookended(actual_output)
+      end
+
       private
 
       attr_reader :expected_output, :program, :output_processor

spec/support/integration/test_programs/base.rb

@@ -112,7 +112,6 @@ def program
                 color_enabled: #{color_enabled?.inspect},
                 configuration: #{configuration.inspect}
               )
-              test_plan.boot
               #{test_plan_prelude}
               test_plan.#{test_plan_command}
 

spec/support/integration/test_programs/plain.rb

@@ -4,6 +4,12 @@ module TestPrograms
       class Plain < Base
         protected
 
+        def test_plan_prelude
+          <<~PRELUDE.strip
+            test_plan.boot
+          PRELUDE
+        end
+
         def test_plan_command
           "run_plain_test"
         end

spec/support/integration/test_programs/rspec_active_record.rb

@@ -5,7 +5,10 @@ class RSpecActiveRecord < Base
         protected
 
         def test_plan_prelude
-          "test_plan.boot_active_record"
+          <<~PRELUDE.strip
+            test_plan.boot
+            test_plan.boot_active_record
+          PRELUDE
         end
 
         def test_plan_command

spec/support/integration/test_programs/rspec_active_support.rb

@@ -5,7 +5,10 @@ class RSpecActiveSupport < Base
         protected
 
         def test_plan_prelude
-          "test_plan.boot_active_support"
+          <<~PRELUDE.strip
+            test_plan.boot
+            test_plan.boot_active_support
+          PRELUDE
         end
 
         def test_plan_command

spec/support/integration/test_programs/rspec_rails.rb

@@ -5,7 +5,10 @@ class RSpecRails < Base
         protected
 
         def test_plan_prelude
-          "test_plan.boot_active_record"
+          <<~PRELUDE.strip
+            test_plan.boot
+            test_plan.boot_active_record
+          PRELUDE
         end
 
         def test_plan_command

spec/support/integration/test_programs/rspec_rails_engine.rb

@@ -0,0 +1,30 @@
+module SuperDiff
+  module IntegrationTests
+    module TestPrograms
+      class RspecRailsEngine < Base
+        def initialize(*args, combustion_initialize:, **options)
+          super(*args, **options)
+          @combustion_initialize = combustion_initialize
+        end
+
+        protected
+
+        def test_plan_prelude
+          <<~PRELUDE.strip
+            test_plan.boot_rails_engine(
+              combustion_initialize: #{combustion_initialize.inspect}
+            )
+          PRELUDE
+        end
+
+        def test_plan_command
+          "run_rspec_rails_test"
+        end
+
+        private
+
+        attr_reader :combustion_initialize
+      end
+    end
+  end
+end

support/test_plan.rb

@@ -110,6 +110,11 @@ def boot_rails
     boot_active_record
   end
 
+  def boot_rails_engine(combustion_initialize: [])
+    require "combustion"
+    Combustion.initialize!(*combustion_initialize)
+  end
+
   def run_plain_test
     run_test_with_libraries("super_diff/rspec")
   end

zeus.json

@@ -12,6 +12,7 @@
       "boot_rails": {
         "run_rspec_rails_test": []
       }
-    }
+    },
+    "boot_rails_engine": []
   }
 }