test_that('mase', {
    f <- 1:10 + 0.2
    r <- 1:10

    expect_equal(mase(f, r), 0.2 * 10 / ((10/9) * 9))
    expect_error(mase(1:10, 1:9))
    expect_error(mase(1, 2))
    expect_error(mase(c(1:5, NA), 1:6))
})