Use viridis as default for ordered factors

NAMESPACE

@@ -401,6 +401,7 @@ export(scale_colour_grey)
 export(scale_colour_hue)
 export(scale_colour_identity)
 export(scale_colour_manual)
+export(scale_colour_ordinal)
 export(scale_colour_viridis_c)
 export(scale_colour_viridis_d)
 export(scale_fill_brewer)
@@ -416,6 +417,7 @@ export(scale_fill_grey)
 export(scale_fill_hue)
 export(scale_fill_identity)
 export(scale_fill_manual)
+export(scale_fill_ordinal)
 export(scale_fill_viridis_c)
 export(scale_fill_viridis_d)
 export(scale_linetype)

NEWS.md

@@ -3,7 +3,8 @@
 * Ordered factors now behave differently from unordered factors in some cases.
   Ordered factors throw a warning when mapped to shape (unordered factors do
   not). Ordered factors do not throw warnings when mapped to size or alpha
-  (unordered factors do) (@karawoo, #1526).
+  (unordered factors do). Viridis is the default colour and fill scale for
+  ordered factors (@karawoo, #1526).
 
 * The `show.legend` parameter now accepts a named logical vector to hide/show
   only some aesthetics in the legend (@tutuchan, #1798)

R/zxx.r

@@ -5,6 +5,11 @@
 #' @usage NULL
 scale_colour_discrete <- scale_colour_hue
 
+#' @export
+#' @rdname scale_viridis
+#' @usage NULL
+scale_colour_ordinal <- scale_colour_viridis_d
+
 #' @export
 #' @rdname scale_gradient
 #' @usage NULL
@@ -48,6 +53,11 @@ scale_colour_date <- function(...,
 #' @usage NULL
 scale_fill_discrete <- scale_fill_hue
 
+#' @export
+#' @rdname scale_viridis
+#' @usage NULL
+scale_fill_ordinal <- scale_fill_viridis_d
+
 #' @export
 #' @rdname scale_gradient
 #' @usage NULL

tests/testthat/test-viridis.R

@@ -1,6 +1,6 @@
 context("Viridis")
 
-df <- data.frame(x = 1, y = 1, z = "a")
+df <- data.frame(x = 1, y = 1, z = "a", tier = factor("low", ordered = TRUE))
 
 test_that("Viridis scale changes point color", {
   p1 <- ggplot(df, aes(x, y, colour = z)) +
@@ -10,3 +10,9 @@ test_that("Viridis scale changes point color", {
   expect_false(layer_data(p1)$colour == layer_data(p2)$colour)
   expect_equal(layer_data(p2)$colour, "#440154FF")
 })
+
+test_that("Viridis scale is used by default for ordered factors" {
+  p <- ggplot(df, aes(x, y, colour = tier)) + geom_point()
+
+  expect_equal(layer_data(p)$colour, "#440154FF")
+})