Enable 2D structures as aesthetics

NEWS.md

@@ -1,5 +1,7 @@
 # ggplot2 (development version)
 
+* (internal) removed barriers for using 2D structures as aesthetics 
+ (@teunbrand, #4189).
 * The `summary()` method for ggplots is now more terse about facets 
  (@teunbrand, #5989).
 * `guide_bins()`, `guide_colourbar()` and `guide_coloursteps()` gain an `angle`

R/geom-.R

@@ -264,7 +264,7 @@ NULL
 .stroke <- 96 / 25.4
 
 check_aesthetics <- function(x, n) {
- ns <- lengths(x)
+ ns <- list_sizes(x)
  good <- ns == 1L | ns == n
 
  if (all(good)) {

R/layer.R

@@ -58,8 +58,8 @@
 #' `NA`, the default, includes if any aesthetics are mapped.
 #' `FALSE` never includes, and `TRUE` always includes.
 #' It can also be a named logical vector to finely select the aesthetics to
-#' display. To include legend keys for all levels, even 
-#' when no data exists, use `TRUE`. If `NA`, all levels are shown in legend, 
+#' display. To include legend keys for all levels, even
+#' when no data exists, use `TRUE`. If `NA`, all levels are shown in legend,
 #' but unobserved levels are omitted.
 #' @param inherit.aes If `FALSE`, overrides the default aesthetics,
 #' rather than combining with them. This is most useful for helper functions
@@ -326,7 +326,7 @@ Layer <- ggproto("Layer", NULL,
  }
 
  n <- nrow(data)
- aes_n <- lengths(evaled)
+ aes_n <- list_sizes(evaled)
  if (n == 0) {
  # No data, so look at longest evaluated aesthetic
  if (length(evaled) == 0) {
@@ -351,7 +351,7 @@ Layer <- ggproto("Layer", NULL,
  } else {
  evaled$PANEL <- data$PANEL
  }
- evaled <- lapply(evaled, unname)
+ evaled <- lapply(evaled, vec_set_names, names = NULL)
  evaled <- as_gg_data_frame(evaled)
  evaled <- add_group(evaled)
  evaled

R/layout.R

@@ -318,7 +318,7 @@ scale_apply <- function(data, vars, method, scale_id, scales) {
 
  lapply(vars, function(var) {
  pieces <- lapply(seq_along(scales), function(i) {
- scales[[i]][[method]](data[[var]][scale_index[[i]]])
+ scales[[i]][[method]](vec_slice(data[[var]], scale_index[[i]]))
  })
  # Remove empty vectors to avoid coercion issues with vctrs
  pieces[lengths(pieces) == 0] <- NULL

tests/testthat/test-layer.R

@@ -188,3 +188,20 @@ test_that("layer_data returns a data.frame", {
  l <- geom_point(data = nrow)
  expect_snapshot_error(l$layer_data(mtcars))
 })
+
+test_that("data.frames and matrix aesthetics survive the build stage", {
+ df <- data_frame0(
+ x = 1:2,
+ g = matrix(1:4, 2),
+ f = data_frame0(a = 1:2, b = c("c", "d"))
+ )
+
+ p <- layer_data(
+ ggplot(df, aes(x, x, colour = g, shape = f)) +
+ geom_point() +
+ scale_colour_identity() +
+ scale_shape_identity()
+ )
+ expect_vector(p$colour, matrix(NA_integer_, nrow = 0, ncol = 2), size = 2)
+ expect_vector(p$shape, data_frame0(a = integer(), b = character()), size = 2)
+})