tests/testthat/test-vdiffr.R

In const-ae/ggsignif: Significance Brackets for 'ggplot2'

test_that("plots are rendered correctly", {
  skip_on_cran()
  skip_if_not_installed("vdiffr")
  skip_if(getRversion() < "4.1")
  library(ggplot2)

  set.seed(123)
  vdiffr::expect_doppelganger(
    title = "basic plot",
    fig = ggplot(mpg, aes(x = manufacturer, y = displ)) +
      geom_boxplot() +
      stat_signif(
        comparisons = list(c("audi", "ford"), c("hyundai", "nissan")),
        map_signif_level = TRUE,
        test = "wilcox.test", test.args = list(alternative = "two.sided"),
        margin_top = 0.02, step_increase = 0, tip_length = 0.01
      ) +
      theme(axis.text.x = element_text(angle = 90, hjust = 1)) +
      facet_wrap(~ as.factor(year), scale = "free")
  )


  set.seed(123)
  vdiffr::expect_doppelganger(
    title = "flipping aesthetics works",
    fig = ggplot(mpg, aes(class, hwy)) +
      geom_boxplot() +
      geom_signif(comparisons = list(
        c("compact", "pickup"),
        c("subcompact", "suv")
      )) +
      coord_flip()
  )

  set.seed(123)
  vdiffr::expect_doppelganger(
    title = "geom works the same way as stat",
    fig = ggplot(mpg, aes(x = manufacturer, y = displ)) +
      geom_boxplot() +
      geom_signif(
        comparisons = list(c("audi", "ford"), c("hyundai", "nissan")),
        annotations = c("Interesting", "Too far apart"),
        test = "wilcox.test",
        test.args = list(alternative = "two.sided"),
        margin_top = 0.02,
        step_increase = 0,
        tip_length = 0.01
      ) +
      theme(axis.text.x = element_text(angle = 90, hjust = 1)) +
      facet_wrap(~ as.factor(year), scale = "free")
  )

  dat <- data.frame(
    Group = c("S1", "S1", "S2", "S2"),
    Sub = c("A", "B", "A", "B"),
    Value = c(3, 5, 7, 8)
  )

  set.seed(123)
  vdiffr::expect_doppelganger(
    title = "geom works with identity",
    fig = ggplot(dat, aes(Group, Value)) +
      geom_bar(aes(fill = Sub),
        stat = "identity",
        position = "dodge",
        width = .5
      ) +
      geom_signif(
        stat = "identity",
        data = data.frame(
          m = c(0.875, 1.875),
          xend = c(1.125, 2.125),
          n = c(5.8, 8.5),
          annotation = c("***", "NS")
        ),
        aes(
          x = m,
          xend = xend,
          y = n,
          yend = n,
          annotation = annotation
        )
      ) +
      geom_signif(
        comparisons = list(c("S1", "S2")),
        annotations = "***",
        y_position = 9.3,
        tip_length = 0
      ) +
      scale_fill_manual(values = c("grey80", "grey20"))
  )
})

test_that("method which return text works - snapshot", {
  magnitude_test <- function(x, y, ...) {
    change <- mean(y) / mean(x)
    p <- t.test(x, y)$p.value
    stars <- if (p < 0.001) {
      "***"
    } else if (p < 0.01) {
      "**"
    } else if (p < 0.05) {
      "*"
    } else {
      ""
    }
    list(p.value = paste0(signif(change, digits = 2), stars))
  }

  p <- ggplot(mpg, aes(x = manufacturer, y = displ)) +
    geom_boxplot() +
    stat_signif(
      comparisons = list(c("audi", "ford"), c("hyundai", "nissan")),
      test = magnitude_test,
      margin_top = 0.02, step_increase = 0, tip_length = 0.01
    ) +
    theme(axis.text.x = element_text(angle = 90, hjust = 1)) +
    facet_wrap(~ as.factor(year), scale = "free")

  vdiffr::expect_doppelganger(
    title = "stat-signif-magnitude",
    fig = p
  )
})


test_that("identical annotations are plotted separetly - snapshot", {
  dat <- data.frame(
    Group = c("S1", "S1", "S2", "S2"),
    Sub = c("A", "B", "A", "B"),
    Value = c(3, 5, 7, 8)
  )

  p <- ggplot(dat, aes(Group, Value)) +
    geom_bar(aes(fill = Sub), stat = "identity", position = "dodge", width = .5) +
    geom_signif(
      comparisons = list(c("S1", "S2")), annotations = "***",
      y_position = 9.3, tip_length = 0, vjust = 0.4
    ) +
    geom_signif(
      stat = "identity",
      data = data.frame(
        x = c(0.875, 1.875), xend = c(1.125, 2.125),
        y = c(5.8, 8.5), annotation = c("**", "**")
      ),
      aes(
        x = x,
        xend = xend,
        y = y,
        yend = y,
        annotation = annotation,
        group = c(1, 2)
      )
    ) +
    scale_fill_manual(values = c("grey80", "grey20"))

  vdiffr::expect_doppelganger(
    title = "identical annotations",
    fig = p
  )
})