Ensure precedence of options and add tests

R/animate_options.R

                             ease_other = list(y = "cubic-out", x = "cubic-in")),
     anim_options()
   )
-  if (is.null(ao_custom)) ao_default else merge(ao_custom, ao_default)
+  if (is.null(ao_custom)) {
+    # User set globals override defaults
+    ao_custom <- get_anim_opt()
+  } else {
+    # Opts from function call override user-set globals
+    ao_custom <- merge(ao_custom, get_anim_opt())
+  }
+  # function > user-set global > default (> global default)
+  if (!is.null(ao_custom)) merge(ao_custom, ao_default) else ao_default
 }
 
 # Font Size Setters and Getters -------------------------------------------

tests/testthat/test-anim_options.R

   expect_equal(get_anim_opt("state_length"), 1)
   expect_equal(get_anim_opt(), anim_options(2, 1, text_size = 5, title_size = 10))
 
-  anim_options_set(anim_options())
+  anim_options_set()
   expect_equal(get_anim_opt("transition_length"), plot_settings$default$transition_length)
 
   anim_options_set(anim_options(enter = enter_appear(early = TRUE)))
   expect_equal(names(get_anim_opt("enter")), "enter_appear(early = TRUE)")
   expect_s3_class(get_anim_opt("enter")[[1]], "ggproto")
+
+  anim_options_set()
+})
+
+test_that("precedence: function > user-set global > default (> global default)", {
+  ao_function <- anim_options(ease_default = "linear")
+  ao_global <- anim_options(ease_default = "cubic", text_family = "Arial")
+  expect_equal(default_anim_opts("gather", ao_function)$ease_default, "linear")
+
+  anim_options_set(ao_global)
+  expect_equal(default_anim_opts("gather")$ease_default, "cubic")
+  expect_equal(default_anim_opts("gather", ao_function)$ease_default, "linear")
+
+  ao_default <- default_anim_opts("gather", ao_function) # inside animate_ function
+  ao_final <- validate_anim_opts(ao_default)             # just before animate_plot() or static_plot()
+  expect_equal(ao_final$ease_default, "linear")
+  expect_equal(ao_final$text_family, "Arial")
+  expect_equivalent(names(ao_final$ease_other), c("y", "x"))
+  expect_equal(ao_final$title_family, plot_settings$default$title_family)
+
+  anim_options_set()
 })