class RSpec::Mocks::Matchers::Receive

def warn_if_any_instance(expression, subject)
  if AnyInstance::Recorder === subject
    RSpec.warning(
      "`#{expression}(#{subject.klass}.any_instance).to` " <<
      "is probably not what you meant, it does not operate on " <<
      "any instance of `#{subject.klass}`. " <<
      "Use `#{expression}_any_instance_of(#{subject.klass}).to` instead."
    )
  end
end