expect_equivalent_images: Test if two image files are equivalent

Description

Test if two image files are equivalent

Usage

expect_equivalent_images(
  current,
  target,
  tol = getOption("tinysnapshot_tol", default = 0),
  metric = getOption("tinysnapshot_metric", default = "AE"),
  fuzz = getOption("tinysnapshot_fuzz", default = 0),
  style = getOption("tinysnapshot_plot_diff_style", default = c("old", "new", "diff")),
  review = getOption("tinysnapshot_plot_review", default = TRUE),
  diffpath = NULL
)

Value

A tinytest object. A tinytest object is a logical with attributes holding information about the test that was run

Arguments

current: path to an image file
target: path to an image file
tol: distance estimates larger than this threshold will trigger a test failure. Scale depends on the metric argument. With the default metric="AE" (absolute error), the tolerance corresponds roughly to the number of pixels of difference between the plot and the reference image.
metric: string with a metric from magick::metric_types() such as "AE" or "phash".
fuzz: relative color distance between 0 and 100 to be considered similar.
style: A character vector to control the panels of the diff image saved to file. The order and number of entries controls the side-by-side panels. Allowable values are: "old", "new", "diff".
review: logical. TRUE if a a diff plot should be saved to file for review when the expectation fails.
diffpath: path where to save an image which shows the differences between current and target. NULL means that the diff image is not saved.