Cannot update the `width` `geom` default for `geom_bar`/`geom_col` and `geom_errorbar`

[davidhodge931]

With the DEV version of ggplot2

library(tidyverse)

update_geom_defaults("bar", aes(width = 0.1))
update_geom_defaults("errorbar", aes(width = 0.1))

GeomBar$default_aes
#> Aesthetic mapping: 
#> * `colour`    -> NA
#> * `fill`      -> `from_theme(col_mix(ink, paper, 0.35))`
#> * `linewidth` -> `from_theme(borderwidth)`
#> * `linetype`  -> `from_theme(bordertype)`
#> * `alpha`     -> NA
#> * `width`     -> 0.1
GeomErrorbar$default_aes
#> Aesthetic mapping: 
#> * `colour`    -> `from_theme(ink)`
#> * `linewidth` -> `from_theme(linewidth)`
#> * `linetype`  -> `from_theme(linetype)`
#> * `width`     -> 0.1
#> * `alpha`     -> NA

data.frame(
  trt = factor(c(1, 1, 2, 2)),
  resp = c(1, 5, 3, 4),
  group = factor(c(1, 2, 1, 2)),
  upper = c(1.1, 5.3, 3.3, 4.2),
  lower = c(0.8, 4.6, 2.4, 3.6)
) |>
  ggplot(aes(
    x = trt,
    y = resp,
    ymin = lower,
    ymax = upper,
    colour = group,
    fill = group,
  )) +
  geom_col(position = "dodge") +
  geom_errorbar(position = "dodge")

^{Created on 2024-12-10 with reprex v2.1.1}

[teunbrand]

The width defaults are just practically never invoked because widths get inferred during plot building based. The updating itself works as you show in your example. I think the position adjustments and data resolutions contribute to the width under normal circumstances.

[teunbrand]

I think this issue might be a duplicate of #2800, which has #6065 pending.

[davidhodge931]

Awesome, great work @teunbrand!