isssue in vignette #927
Description
This commit caused the following example to error 133f559.
What the correct code should be?
https://r-tmap.github.io/tmap/dev/articles/tmap_sneak_peek.html#aesthetics
# tmap v4 (before the commit)
tm_shape(World) +
tm_polygons(fill = "HPI",
fill.scale = tm_scale_intervals(values = "purple_green"),
fill.legend = tm_legend(title = "Happy Planet Index"))