test_that("`aggreagate_fun` works with input and returns expected list", {
  b<-aggregate_func(data.frame(numerator=c(100, 150,180,89,120, 225),
                             denominator=c(102, 135, 165,95,100, 220),
                             group=factor(c("a","a","a", "b","b","c"))))
  expect_s3_class(b, "data.frame")
  expect_length(b, 4)
  expect_length(b$group, 3)
  expect_equal(round(b$rr,6), c(1.069652, 1.071795, 1.022727))

})