describe("discard", {
    ee <- expect_equal

    describe("discard.Container", {
        test_that("discard works for Container objects", {
            co <- container("a", "b", "a", mean, mean, NULL)
            co2 <- clone(co)
            ee(discard(co), co2)
            ee(discard(co, "a", mean, NULL), container("b", "a", mean))
            original_was_not_touched <- all.equal(co, co2)
            expect_true(original_was_not_touched)

            ee(ref_discard(co, "a", mean, NULL), container("b", "a", mean))
            discard_was_done_on_original <- all.equal(co, container("b", "a", mean))
            expect_true(discard_was_done_on_original)
            ee(discard(co, "x"), co)

            co2 <- clone(co)
            nothing_was_removed <- all.equal(co, co2)
            expect_true(nothing_was_removed)

            d <- dict(a = 1, b = 2, f = mean)
            d2 <- clone(d)
            ee(discard(d, 1, 2, mean), dict())
            original_was_not_touched <- all.equal(d, d2)
            expect_true(original_was_not_touched)

            ee(discard(d, "x"), d)
        })
    })
})