tests/testthat/test-geom_intron.R

In dzhang32/ggtranscript: Visualizing Transcript Structure and Annotation using 'ggplot2'

test_introns <-
    dplyr::tibble(
        strand = c("+", "-"),
        tx = c("A", "B"),
        start = c(201, 601),
        end = c(299, 649),
        type = "intron"
    )

# create base plot to be used in downstream tests
test_introns_plot <- test_introns %>%
    ggplot2::ggplot(aes(
        xstart = start,
        xend = end,
        y = tx
    ))

##### geom_intron #####

testthat::test_that(
    "geom_intron() works correctly",
    {
        base_geom_intron <- test_introns_plot +
            geom_intron()
        w_param_geom_intron <- test_introns_plot +
            geom_intron(colour = "blue", linewidth = 2)
        w_aes_geom_intron <- test_introns_plot +
            geom_intron(aes(colour = tx, linewidth = c(1L, 2L)))
        w_facet_geom_intron <- test_introns_plot +
            geom_intron() +
            ggplot2::facet_wrap(~tx)

        vdiffr::expect_doppelganger(
            "Base geom_intron plot",
            base_geom_intron
        )
        vdiffr::expect_doppelganger(
            "With param geom_intron plot",
            w_param_geom_intron
        )
        vdiffr::expect_doppelganger(
            "With aes geom_intron plot",
            w_aes_geom_intron
        )
        vdiffr::expect_doppelganger(
            "With facet geom_intron plot",
            w_facet_geom_intron
        )
    }
)

testthat::test_that(
    "geom_intron(strand = x) works correctly",
    {
        minus_strand <- test_introns_plot +
            geom_intron(strand = "-")
        factor_strand <- test_introns_plot +
            geom_intron(strand = factor("-"))
        as_aes_strand <- test_introns_plot +
            geom_intron(aes(strand = strand))

        vdiffr::expect_doppelganger(
            "Minus strand plot",
            minus_strand
        )
        vdiffr::expect_doppelganger(
            "factor strand plot",
            factor_strand
        )
        vdiffr::expect_doppelganger(
            "As aes strand plot",
            as_aes_strand
        )
    }
)

testthat::test_that(
    "geom_intron(arrow.min.intron.length = x) works correctly",
    {
        base_arrow.min <- test_introns_plot +
            geom_intron(arrow.min.intron.length = 50)
        w_strand_arrow_min <- test_introns_plot +
            geom_intron(arrow.min.intron.length = 50, strand = "-")

        vdiffr::expect_doppelganger(
            "base arrow.min plot",
            base_arrow.min
        )
        vdiffr::expect_doppelganger(
            "with strand arrow.min plot",
            w_strand_arrow_min
        )
    }
)

testthat::test_that(
    "geom_intron() catches strand input errors",
    {
        na_strand <- test_introns_plot +
            geom_intron(strand = c(NA, rep("+", nrow(test_introns) - 1)))
        a_strand <- test_introns_plot +
            geom_intron(strand = "a")
        int_strand <- test_introns_plot +
            geom_intron(aes(strand = start))
        # seems to require print to catch error
        expect_error(
            print(na_strand),
            "strand values must be one of"
        )
        expect_error(
            print(a_strand),
            "strand values must be one of"
        )
        expect_error(
            print(int_strand),
            "strand values must be one of"
        )
    }
)

testthat::test_that(
    "geom_intron() catches arrow.min.intron.length input errors",
    {
        neg_arrow.min <- test_introns_plot +
            geom_intron(arrow.min.intron.length = -1)
        chr_arrow.min <- test_introns_plot +
            geom_intron(arrow.min.intron.length = "1")
        # seems to require print to catch error
        expect_error(
            print(neg_arrow.min),
            "arrow.min.intron.length must be "
        )
        expect_error(
            print(chr_arrow.min),
            "arrow.min.intron.length must be "
        )
    }
)