Do not change method visibility when stubbing private class methods. (#…

…1277)

Changelog.md

@@ -9,6 +9,10 @@ Enhancements:
   `expect(Class).to receive(:method).exactly(1).time`.
   (Pistos, Benoit Tigeot, #1271)
 
+Bug Fixes:
+
+* Do not change the visibility of stubbed private class methods. (Kevin Boschert)
+
 ### 3.8.0 / 2018-08-04
 [Full Changelog](http://github.com/rspec/rspec-mocks/compare/v3.7.0...v3.8.0)
 

lib/rspec/mocks/method_double.rb

@@ -59,7 +59,7 @@ def define_proxy_method
         return if @method_is_proxied
 
         save_original_implementation_callable!
-        definition_target.class_exec(self, method_name, visibility) do |method_double, method_name, visibility|
+        definition_target.class_exec(self, method_name, @original_visibility || visibility) do |method_double, method_name, visibility|
           define_method(method_name) do |*args, &block|
             method_double.proxy_method_invoked(self, *args, &block)
           end

spec/rspec/mocks/stub_spec.rb

@@ -19,6 +19,7 @@ def existing_instance_method
             existing_private_instance_method
           end
 
+        private
           def existing_private_instance_method
             :original_value
           end
@@ -84,6 +85,16 @@ def existing_private_instance_method
         expect { @stub.dup.foobar }.to raise_error NoMethodError, /foobar/
       end
 
+      it "remains private when it stubs a private instance method" do
+        allow(@instance).to receive(:existing_private_instance_method).and_return(1)
+        expect { @instance.existing_private_instance_method }.to raise_error NoMethodError, /private method `existing_private_instance_method/
+      end
+
+      it "remains private when it stubs a private class method" do
+        allow(@class).to receive(:existing_private_class_method).and_return(1)
+        expect { @class.existing_private_class_method }.to raise_error NoMethodError, /private method `existing_private_class_method/
+      end
+
       context "using `with`" do
         it 'determines which value is returned' do
           allow(@stub).to receive(:foo).with(1) { :one }