tests/testthat/test-save_png.R

In dzhang32/rutils: `rutils` is a home for my commonly used R utility functions

test_that("save_png has correct output", {
  expect_snapshot_file(
    save_png(
      plot_code = {
        plot(x = 1:5)
      },
      path = file.path(tempdir(), "test_plot_1.png"),
    ),
    "test_plot_1.png"
  )

  # works with pipe
  expect_snapshot_file(
    {
      plot(x = 1:5)
    } %>%
      save_png(
        path = file.path(tempdir(), "test_plot_2.png"),
        width = 5,
        height = 5,
        res = 300,
      ),
    "test_plot_2.png"
  )

  # works with ggplots
  expect_snapshot_file(
    save_png(
      plot_code = {
        test_ggplot <- dplyr::tibble(x = 1:5, y = 1:5) %>%
          ggplot2::ggplot(ggplot2::aes(x, y)) +
          ggplot2::geom_point()
        print(test_ggplot)
      },
      path = file.path(tempdir(), "test_plot_3.png"),
    ),
    "test_plot_3.png"
  )

  expect_true(file.exists(file.path(tempdir(), "test_plot_1.png")))
  expect_true(file.exists(file.path(tempdir(), "test_plot_2.png")))
  expect_true(file.exists(file.path(tempdir(), "test_plot_3.png")))
})