From e991246981343268fdbc483ff0269571e72aaac4 Mon Sep 17 00:00:00 2001
From: Teun van den Brand <tahvdbrand@gmail.com>
Date: Mon, 4 Dec 2023 14:37:41 +0100
Subject: [PATCH 1/3] adjust `draw_key_{v}path()`

---
 R/legend-draw.R | 19 ++++++++++++++++---
 1 file changed, 16 insertions(+), 3 deletions(-)

diff --git a/R/legend-draw.R b/R/legend-draw.R
index 5f8c202f07..6794e2d652 100644
--- a/R/legend-draw.R
+++ b/R/legend-draw.R
@@ -160,8 +160,7 @@ draw_key_path <- function(data, params, size) {
   } else {
     data$linetype[is.na(data$linetype)] <- 0
   }
-
-  segmentsGrob(0.1, 0.5, 0.9, 0.5,
+  grob <- segmentsGrob(0.1, 0.5, 0.9, 0.5,
     gp = gpar(
       col = alpha(data$colour %||% data$fill %||% "black", data$alpha),
       fill = alpha(params$arrow.fill %||% data$colour
@@ -172,12 +171,19 @@ draw_key_path <- function(data, params, size) {
     ),
     arrow = params$arrow
   )
+  if (!is.null(params$arrow)) {
+    angle <- deg2rad(params$arrow$angle)
+    length <- convertUnit(params$arrow$length, "cm", valueOnly = TRUE)
+    attr(grob, "width")  <- cos(angle) * length * 1.25
+    attr(grob, "height") <- sin(angle) * length * 2
+  }
+  grob
 }
 
 #' @export
 #' @rdname draw_key
 draw_key_vpath <- function(data, params, size) {
-  segmentsGrob(0.5, 0.1, 0.5, 0.9,
+  grob <- segmentsGrob(0.5, 0.1, 0.5, 0.9,
     gp = gpar(
       col = alpha(data$colour %||% data$fill %||% "black", data$alpha),
       lwd = (data$linewidth %||% 0.5) * .pt,
@@ -186,6 +192,13 @@ draw_key_vpath <- function(data, params, size) {
     ),
     arrow = params$arrow
   )
+  if (!is.null(params$arrow)) {
+    angle <- deg2rad(params$arrow$angle)
+    length <- convertUnit(params$arrow$length, "cm", valueOnly = TRUE)
+    attr(grob, "width")  <- sin(angle) * length * 2
+    attr(grob, "height") <- cos(angle) * length * 1.25
+  }
+  grob
 }
 
 #' @export

From ea80d8cdb1f4e808975610ee3a8bdc838ec1d795 Mon Sep 17 00:00:00 2001
From: Teun van den Brand <tahvdbrand@gmail.com>
Date: Mon, 4 Dec 2023 14:37:48 +0100
Subject: [PATCH 2/3] adjust derived keys

---
 R/legend-draw.R | 17 +++++++++++++----
 1 file changed, 13 insertions(+), 4 deletions(-)

diff --git a/R/legend-draw.R b/R/legend-draw.R
index 6794e2d652..0c8bd42627 100644
--- a/R/legend-draw.R
+++ b/R/legend-draw.R
@@ -228,10 +228,14 @@ draw_key_linerange <- function(data, params, size) {
 #' @export
 #' @rdname draw_key
 draw_key_pointrange <- function(data, params, size) {
-  grobTree(
-    draw_key_linerange(data, params, size),
+  linerange <- draw_key_linerange(data, params, size)
+  grob <- grobTree(
+    linerange,
     draw_key_point(transform(data, size = (data$size %||% 1.5) * 4), params)
   )
+  attr(grob, "width")  <- attr(linerange, "width")
+  attr(grob, "height") <- attr(linerange, "height")
+  grob
 }
 
 #' @export
@@ -240,10 +244,15 @@ draw_key_smooth <- function(data, params, size) {
   data$fill <- alpha(data$fill %||% "grey60", data$alpha)
   data$alpha <- 1
 
-  grobTree(
+  path <- draw_key_path(data, params, size)
+
+  grob <- grobTree(
     if (isTRUE(params$se)) rectGrob(gp = gpar(col = NA, fill = data$fill)),
-    draw_key_path(data, params, size)
+    path
   )
+  attr(grob, "width") <- attr(path, "width")
+  attr(grob, "height") <- attr(path, "height")
+  grob
 }
 
 #' @export

From f16d6c271f8590d1652746368ad6dc4cef3763e5 Mon Sep 17 00:00:00 2001
From: Teun van den Brand <tahvdbrand@gmail.com>
Date: Mon, 4 Dec 2023 14:37:55 +0100
Subject: [PATCH 3/3] Add news bullet

---
 NEWS.md | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/NEWS.md b/NEWS.md
index 1cbd49cf1d..8cfd95732e 100644
--- a/NEWS.md
+++ b/NEWS.md
@@ -1,5 +1,7 @@
 # ggplot2 (development version)
 
+* Legend keys that can draw arrows have their size adjusted for arrows.
+
 * The `legend.key` theme element is set to inherit from the `panel.background`
   theme element. The default themes no longer set the `legend.key` element.
   This causes a visual change with the default `theme_gray()` (#5549).