Default colour aesthetic in geom_polygon() set to string "NA"?

[mdlama]

There might be a bug in the default aesthetics for geom_polygon(). It appears to be set to the string "NA" rather than NA. Here's a minimal reprex:

library(ggplot2)

geom_polygon()$geom$default_aes
#> Aesthetic mapping: 
#> * `colour`   -> "NA"
#> * `fill`     -> "grey20"
#> * `size`     -> 0.5
#> * `linetype` -> 1
#> * `alpha`    -> NA
#> * `subgroup` -> NULL

^{Created on 2020-12-01 by the reprex package (v0.3.0.9001)}

[yutannihilation]

Good catch. Probably "NA" still works because farver interprets it the same as NA (this is consistent with the behaviour of grDevices::col2rgb()), but I agree this should be NA. Do you want to contribute a pull request?

farver::decode_colour(NA)
#>       r  g  b
#> [1,] NA NA NA
farver::decode_colour("NA")
#>       r  g  b
#> [1,] NA NA NA

^{Created on 2020-12-02 by the reprex package (v0.3.0)}

[mdlama]

Sure! I'll reference this issue in the pull request. Thanks!