diff --git a/spec/rubocop/cop/thread_safety/mutable_class_instance_variable_spec.rb b/spec/rubocop/cop/thread_safety/mutable_class_instance_variable_spec.rb
index bc6346b..564b389 100644
--- a/spec/rubocop/cop/thread_safety/mutable_class_instance_variable_spec.rb
+++ b/spec/rubocop/cop/thread_safety/mutable_class_instance_variable_spec.rb
@@ -282,10 +282,16 @@ def some_method
             it_behaves_like 'mutable objects', %("\#{a}")
           end
 
-          context 'when the frozen_string_literal comment is true', unsupported_on: :prism do
-            let(:prefix) { "# frozen_string_literal: true\n#{super()}" }
+          context 'when the frozen_string_literal comment is true' do
+            context 'with Ruby 2.7', unsupported_on: :prism do
+              let(:prefix) { "# frozen_string_literal: true\n#{super()}" }
 
-            it_behaves_like 'immutable objects', %("\#{a}")
+              it_behaves_like 'immutable objects', %("\#{a}")
+            end
+
+            context 'with Ruby 3', :ruby30 do
+              it_behaves_like 'mutable objects', %("\#{a}")
+            end
           end
 
           context 'when the frozen_string_literal comment is false' do
@@ -605,10 +611,18 @@ def assignment?
             it_behaves_like 'mutable objects', %("\#{a}")
           end
 
-          context 'when the frozen_string_literal comment is true', unsupported_on: :prism do
-            let(:prefix) { "# frozen_string_literal: true\n#{super()}" }
+          context 'when the frozen_string_literal comment is true' do
+            context 'with Ruby 2.7', unsupported_on: :prism do
+              let(:prefix) { "# frozen_string_literal: true\n#{super()}" }
 
-            it_behaves_like 'immutable objects', %("\#{a}")
+              it_behaves_like 'immutable objects', %("\#{a}")
+            end
+
+            context 'with Ruby 3', :ruby30 do
+              let(:prefix) { "# frozen_string_literal: true\n#{super()}" }
+
+              it_behaves_like 'mutable objects', %("\#{a}")
+            end
           end
 
           context 'when the frozen_string_literal comment is false' do
diff --git a/spec/spec_helper.rb b/spec/spec_helper.rb
index be1363f..0eaadf4 100644
--- a/spec/spec_helper.rb
+++ b/spec/spec_helper.rb
@@ -46,4 +46,11 @@
   config.order = :random
 
   Kernel.srand config.seed
+
+  config.include_context 'ruby 2.7', :ruby27
+  config.include_context 'ruby 3.0', :ruby30
+  config.include_context 'ruby 3.1', :ruby31
+  config.include_context 'ruby 3.2', :ruby32
+  config.include_context 'ruby 3.3', :ruby33
+  config.include_context 'ruby 3.4', :ruby34
 end