Handle fine-grained show.legend properly (#3490)

Author: yutannihilation

NEWS.md

@@ -57,6 +57,8 @@
 
 * `geom_sf()` now removes rows that contain missing `shape`/`size`/`colour` (#3483, @yutannihilation)
 
+* Fix a bug when `show.legend` is a named logical vector (#3461, @yutannihilation).
+
 # ggplot2 3.2.1
 
 This is a patch release fixing a few regressions introduced in 3.2.0 as well as

R/guide-colorbar.r

@@ -244,10 +244,28 @@ guide_geom.colorbar <- function(guide, layers, default_mapping) {
   guide_layers <- lapply(layers, function(layer) {
     matched <- matched_aes(layer, guide, default_mapping)
 
-    if (length(matched) > 0 && (isTRUE(is.na(layer$show.legend)) || isTRUE(layer$show.legend))) {
+    if (length(matched) == 0) {
+      # This layer does not use this guide
+      return(NULL)
+    }
+
+    # check if this layer should be included, different behaviour depending on
+    # if show.legend is a logical or a named logical vector
+    if (is_named(layer$show.legend)) {
+      layer$show.legend <- rename_aes(layer$show.legend)
+      show_legend <- layer$show.legend[matched]
+      # we cannot use `isTRUE(is.na(show_legend))` here because
+      # 1. show_legend can be multiple NAs
+      # 2. isTRUE() was not tolerant for a named TRUE
+      show_legend <- show_legend[!is.na(show_legend)]
+      include <- length(show_legend) == 0 || any(show_legend)
+    } else {
+      include <- isTRUE(is.na(layer$show.legend)) || isTRUE(layer$show.legend)
+    }
+
+    if (include) {
       layer
     } else {
-      # This layer does not use this guide
       NULL
     }
   })

R/guide-legend.r

@@ -250,10 +250,14 @@ guide_geom.legend <- function(guide, layers, default_mapping) {
 
       # check if this layer should be included, different behaviour depending on
       # if show.legend is a logical or a named logical vector
-      if (!is.null(names(layer$show.legend))) {
+      if (is_named(layer$show.legend)) {
         layer$show.legend <- rename_aes(layer$show.legend)
-        include <- is.na(layer$show.legend[matched]) ||
-          layer$show.legend[matched]
+        show_legend <- layer$show.legend[matched]
+        # we cannot use `isTRUE(is.na(show_legend))` here because
+        # 1. show_legend can be multiple NAs
+        # 2. isTRUE() was not tolerant for a named TRUE
+        show_legend <- show_legend[!is.na(show_legend)]
+        include <- length(show_legend) == 0 || any(show_legend)
       } else {
         include <- isTRUE(is.na(layer$show.legend)) || isTRUE(layer$show.legend)
       }

tests/testthat/test-guides.R

@@ -44,6 +44,11 @@ test_that("show.legend handles named vectors", {
   p <- ggplot(df, aes(x = x, y = y, color = x, shape = factor(y))) +
     geom_point(size = 20, show.legend = c(color = FALSE, shape = FALSE))
   expect_equal(n_legends(p), 0)
+
+  # c.f.https://github.com/tidyverse/ggplot2/issues/3461
+  p <- ggplot(df, aes(x = x, y = y, color = x, shape = factor(y))) +
+    geom_point(size = 20, show.legend = c(shape = FALSE, color = TRUE))
+  expect_equal(n_legends(p), 1)
 })
 
 test_that("axis_label_overlap_priority always returns the correct number of elements", {