There is no need to define test if a connection does not support primary_key

activerecord/test/cases/primary_keys_test.rb

@@ -135,22 +135,20 @@ def test_supports_primary_key
     end
   end
 
-  def test_primary_key_returns_value_if_it_exists
-    klass = Class.new(ActiveRecord::Base) do
-      self.table_name = 'developers'
-    end
+  if ActiveRecord::Base.connection.supports_primary_key?
+    def test_primary_key_returns_value_if_it_exists
+      klass = Class.new(ActiveRecord::Base) do
+        self.table_name = 'developers'
+      end
 
-    if ActiveRecord::Base.connection.supports_primary_key?
       assert_equal 'id', klass.primary_key
     end
-  end
 
-  def test_primary_key_returns_nil_if_it_does_not_exist
-    klass = Class.new(ActiveRecord::Base) do
-      self.table_name = 'developers_projects'
-    end
+    def test_primary_key_returns_nil_if_it_does_not_exist
+      klass = Class.new(ActiveRecord::Base) do
+        self.table_name = 'developers_projects'
+      end
 
-    if ActiveRecord::Base.connection.supports_primary_key?
       assert_nil klass.primary_key
     end
   end