Prepend openapi! in any case

If you run tests with Minitest at themoment, but without the environment variable `OPENAPI`, you are greeted with an error message.

`undefined method `openapi!' for Api::V0::SomeControllerTest:Class (NoMethodError)`

This is because the current code adds the `openapi!` method only if `OPENAPI` environment variable is set.

This commit modifies the loading logic, always requiring the `minitest` hooks class to be loaded if `Minitest` constant is defined, to avoid issues with RSpec. Then, the `openapi?` and `openapi!` methods are always prepended to `Minitest::Test`, while the modified `run` method and the `after_run` hook are only activated when `OPENAPI` environment variable is set.

lib/rspec/openapi.rb

@@ -10,8 +10,11 @@
 require 'rspec/openapi/schema_merger'
 require 'rspec/openapi/schema_cleaner'
 
-if ENV['OPENAPI']
+if Object.const_defined?('Minitest')
   require 'rspec/openapi/minitest_hooks'
+end
+
+if ENV['OPENAPI'] && Object.const_defined?('RSpec')
   require 'rspec/openapi/rspec_hooks'
 end
 

lib/rspec/openapi/minitest_hooks.rb

@@ -5,11 +5,7 @@
 module RSpec::OpenAPI::Minitest
   Example = Struct.new(:context, :description, :metadata, :file_path)
 
-  module TestPatch
-    def self.prepended(base)
-      base.extend(ClassMethods)
-    end
-
+  module RunPatch
     def run(*args)
       result = super
       if ENV['OPENAPI'] && self.class.openapi?
@@ -22,6 +18,12 @@ def run(*args)
       end
       result
     end
+  end
+
+  module ActivateOpenApiClassMethods
+    def self.prepended(base)
+      base.extend(ClassMethods)
+    end
 
     module ClassMethods
       def openapi?
@@ -35,10 +37,12 @@ def openapi!
   end
 end
 
-Minitest::Test.prepend RSpec::OpenAPI::Minitest::TestPatch
+Minitest::Test.prepend RSpec::OpenAPI::Minitest::ActivateOpenApiClassMethods
+
+if ENV['OPENAPI']
+  Minitest::Test.prepend RSpec::OpenAPI::Minitest::RunPatch
 
-Minitest.after_run do
-  if ENV['OPENAPI']
+  Minitest.after_run do
     result_recorder = RSpec::OpenAPI::ResultRecorder.new(RSpec::OpenAPI.path_records)
     result_recorder.record_results!
     puts result_record.error_message if result_recorder.errors?