merge screenshots

NAMESPACE

@@ -12,7 +12,8 @@ export(examples_app)
 export(get_screenshot_args_attr)
 export(get_screenshot_from_app)
 export(glue_regexp_screenshot_files)
-export(map_snaps_animate)
+export(image_animate_snaps)
+export(image_write_snaps)
 export(mixed_react_tree_app)
 export(mixed_react_tree_server)
 export(mixed_react_tree_ui)

R/shiny2screenshot.R

@@ -236,22 +236,35 @@ glue_regexp_screenshot_files <- function(name = NULL, auto_numbered = TRUE) {
 }
 
 #' @describeIn get_shinytest_screenshots
-#' Return screenshot.
-#' If several, merge into a gif first.
-#' @return Path to image.
+#' Read in screenshot.
+#' If several, animate into a gif.
 #' @param snaps
 #' Vector of file names, as returned by [dir_ls_snaps()]
+#' @inheritParams magick::image_animate
+#' @inheritDotParams magick::image_animate
+#' @return A `magick-image`.
 #' @export
-map_snaps_animate <- function(snaps = fs::path()) {
+image_animate_snaps <- function(snaps = fs::path(), fps = 5,...) {
   if (any(!fs::file_exists(snaps))) rlang::abort("File could not be found.")
   names(snaps) <- fs::path_file(snaps)
+  check_installed_magick()
+  res <- magick::image_read(snaps)
   if (length(snaps) == 1) {
-    return(snaps)
+    res
   } else {
-    check_installed_magick()
+    magick::image_animate(res, fps = fps, ...)
   }
 }
 
+#' @describeIn get_shinytest_screenshots
+#' Write out (merged) screenshots to new path.
+#' @inheritParams magick::image_write
+#' @return Path to the (merged) screenshots.
+#' @export
+image_write_snaps <- function(image, path = withr::local_tempfile()) {
+  magick::image_write(image = image, path = path)
+}
+
 check_installed_magick <- function() {
   rlang::check_installed(
     "magick",

tests/testthat/test-shiny2screenshot.R

@@ -117,7 +117,7 @@ describe("map_snaps_animate", {
     expect_error(map_snaps_animate("i-do-not-exist"))
     expect_error(map_snaps_animate(c("i-do-not-exist", "me-neither")))
   })
-  it("reads in single file", {
+  it("reads in single screenshot", {
     snaps <- dir_ls_snaps(
       test_file = "helpers",
       regexp = glue_regexp_screenshot_files(
@@ -126,10 +126,27 @@ describe("map_snaps_animate", {
       ),
       variant = variant
     )
+    path <- withr::local_tempfile()
     testthat::expect_snapshot_file(
-      path = map_snaps_animate(snaps),
+      path = image_animate_snaps(snaps) |> image_write_snaps(path = path),
       name = "single.png",
       variant = variant
     )
   })
+  it("reads in multiple screenshots", {
+    snaps <- dir_ls_snaps(
+      test_file = "helpers",
+      regexp = glue_regexp_screenshot_files(
+        name = "bins",
+        auto_numbered = FALSE
+      ),
+      variant = variant
+    )
+    path <- withr::local_tempfile()
+    testthat::expect_snapshot_file(
+      path = image_animate_snaps(snaps) |> image_write_snaps(path = path),
+      name = "multiple.gif",
+      variant = variant
+    )
+  })
 })