stat_summary_bin(width) of preferred over default width

NEWS.md

@@ -172,6 +172,7 @@
 * {tibble} is now suggested instead of imported (@teunbrand, #5986)
 * The ellipsis argument is now checked in `fortify()`, `get_alt_text()`, 
   `labs()` and several guides (@teunbrand, #3196).
+* `stat_summary_bin()` no longer ignores `width` parameter (@teunbrand, #4647).
 
 # ggplot2 3.5.1
 

R/stat-summary-bin.R

@@ -79,7 +79,7 @@ StatSummaryBin <- ggproto("StatSummaryBin", Stat,
   compute_group = function(data, scales, fun = NULL,
                            bins = 30, binwidth = NULL, breaks = NULL,
                            origin = NULL, right = FALSE, na.rm = FALSE,
-                           flipped_aes = FALSE) {
+                           flipped_aes = FALSE, width = NULL) {
     data <- flip_data(data, flipped_aes)
     x <- flipped_names(flipped_aes)$x
     breaks <- bin2d_breaks(scales[[x]], breaks, origin, binwidth, bins, right = right)
@@ -89,7 +89,7 @@ StatSummaryBin <- ggproto("StatSummaryBin", Stat,
 
     locs <- bin_loc(breaks, out$bin)
     out$x <- locs$mid
-    out$width <- if (scales[[x]]$is_discrete()) 0.9 else locs$length
+    out$width <- width %||% if (scales[[x]]$is_discrete()) 0.9 else locs$length
     out$flipped_aes <- flipped_aes
     flip_data(out, flipped_aes)
   }

tests/testthat/test-stat-summary.R

@@ -40,8 +40,16 @@ test_that("stat_summary(_bin) work with lambda expressions", {
 
 })
 
+test_that("stat_summary_bin takes user's `width` argument (#4647)", {
+  p <- ggplot(mtcars, aes(mpg, disp)) +
+    stat_summary_bin(
+      fun.data = mean_se, na.rm = TRUE,
+      binwidth = 1, width = 2
+    )
 
-
+  ld <- layer_data(p)
+  expect_equal(unique(ld$width), 2)
+})
 
 test_that("stat_summary_(2d|hex) work with lambda expressions", {