Fill color changes to black when plotting `sfc` objects consisting of `MULTIPOLYGON`s and `POLYGON`s

Hi all,

library(sf)
# two arbitrary multipolygons:
p1 <- st_polygon(list(matrix(c(0, 0, 0, 1, 1, 1, 1, 0, 0, 0), ncol = 2, byrow = TRUE)))
mp1 <- c(p1, p1 + c(2, 2))
p2 <- p1 + c(4, 4)
mp2 <- c(p2, p2 + c(2, 2))

# An `sfc` object with only multipolygons plots nicely:
plot(st_sfc(mp1, mp2))
 
# The fill color of the polygons changes to black when mulitpolygons and polygons are mixed:
plot(st_sfc(mp1, p2))
 
# Specififaction of the `col` argument still works though:
plot(st_sfc(mp1, p2), col = NA)

Cheers

[edzer]

Please run your example before you post.

[edzer]

The issue is that a GEOMETRY sfc object indicates a mix of geometries. If the default col would be NA, points and lines would be plotted invisibly.

Question: should we give col a default depending on the geometry's dimension: NA for dimension 2, 1 (black) otherwise?

[edzer]

The answer was yes.