Map internal ActiveSupport test helpers call to rspec-rails method

This method has been moved in rails/rails@3cece0b
We do not include ActiveSupport::Testing::Assertion at the moment.

To avoid having to deal with complicated scenarios like Minitest errors.
We redefine our own methods in rspec-rails.

Related: rails/rails#40780

Author: benoittgt

lib/rspec/rails.rb

@@ -8,6 +8,7 @@
 # Load the rspec-rails parts
 require 'rspec/rails/view_rendering'
 require 'rspec/rails/matchers'
+require 'rspec/rails/active_support_testing_assertion'
 require 'rspec/rails/fixture_support'
 require 'rspec/rails/file_fixture_support'
 require 'rspec/rails/fixture_file_upload_support'

lib/rspec/rails/active_support_testing_assertion.rb

@@ -0,0 +1,13 @@
+module RSpec
+  module Rails
+    # @private
+    # In Rails 6.1 some methods from ActiveSupport::Testcase
+    # has been moved to ActiveSupport::Testing::Assertion.
+    # Few of them are required in different scenarios.
+    module ActiveSupportTestingAssertion
+      def assert_nothing_raised(&block)
+        expect(&block).to_not raise_error
+      end
+    end
+  end
+end

lib/rspec/rails/configuration.rb

@@ -85,6 +85,10 @@ def self.initialize_configuration(config) # rubocop:disable Metrics/MethodLength
         config.include RSpec::Rails::FileFixtureSupport
       end
 
+      if ::Rails.version.to_f >= 6.1
+        config.include RSpec::Rails::ActiveSupportTestingAssertion
+      end
+
       # Add support for fixture_path on fixture_file_upload
       config.include RSpec::Rails::FixtureFileUploadSupport
 

spec/rspec/rails/active_support_testing_assertion_spec.rb

@@ -0,0 +1,11 @@
+module RSpec::Rails
+  RSpec.describe ActiveSupportTestingAssertion do
+    it 'assert_nothing_raised is not undefined' do
+      expect {
+        assert_nothing_raised do
+          :foo
+        end
+      }.to_not raise_error
+    end
+  end
+end