test_that("inset() creates a patch_inset object with default parameters", {
    p1 <- ggplot(mtcars) +
        geom_point(aes(mpg, disp))
    p2 <- ggplot(mtcars) +
        geom_boxplot(aes(factor(gear), disp))

    pi <- inset(p2)

    expect_s7_class(pi, inset)
    expect_s3_class(pi@grob, "grob")
    expect_equal(pi@align, "panel")
    expect_equal(pi@clip, "on")
    expect_true(pi@on_top)
})

test_that("inset() respects vp argument and sets viewport on grob", {
    p2 <- ggplot(mtcars) +
        geom_boxplot(aes(factor(gear), disp))
    vp <- viewport(x = 0.7, y = 0.7, width = 0.3, height = 0.3)

    pi <- inset(p2, vp = vp)
    expect_s7_class(pi, inset)
    expect_identical(pi@vp, vp)
})

test_that("grid.draw inset calls next method on grob", {
    p2 <- ggplot(mtcars) +
        geom_boxplot(aes(factor(gear), disp))
    pi <- inset(p2, vp = viewport(width = 0.5, height = 0.5))
    expect_doppelganger(
        "grid.draw inset matches inner grob",
        grid.draw(pi)
    )
})

test_that("ggplot_add inset calls make_wrap", {
    p <- ggplot(mtcars) +
        geom_point(aes(mpg, disp))
    p2 <- ggplot(mtcars) +
        geom_boxplot(aes(factor(gear), disp))
    pi <- inset(p2, vp = viewport(width = 0.5, height = 0.5))
    expect_doppelganger(
        "ggplot_add inset produces correct plot output",
        ggplot_add(pi, p)
    )
})