warping fails in tmap4

[Nowosad]

I know that the raster.warp argument is removed in tmap4. However, it seems not ideal that the current version of tmap cannot warp a raster that the previous version was able to do:

library(tmap)
data("land")

elev = land[4]
tm_shape(elev) +
  tm_raster()
#> [scale] tm_raster:() the data variable assigned to 'col' contains positive and negative values, so midpoint is set to 0. Set 'midpoint = NA' in 'fill.scale = tm_scale_intervals(<HERE>)' to use all visual values (e.g. colors)

# in tmap3 -- this would apply raster warping
tm_shape(elev, crs = "EPSG:8857") +
  tm_raster()
#> Warning: Unable to warp stars. Stars will be transformed now (which will take
#> some time).
#> [scale] tm_raster:() the data variable assigned to 'col' contains positive and negative values, so midpoint is set to 0. Set 'midpoint = NA' in 'fill.scale = tm_scale_intervals(<HERE>)' to use all visual values (e.g. colors)

# in tmap3 -- this would result in a curvilinear raster
tm_shape(elev, crs = "EPSG:8857", raster.warp = FALSE) +
  tm_raster()
#> Warning: Unable to warp stars. Stars will be transformed now (which will take
#> some time).
#> [scale] tm_raster:() the data variable assigned to 'col' contains positive and negative values, so midpoint is set to 0. Set 'midpoint = NA' in 'fill.scale = tm_scale_intervals(<HERE>)' to use all visual values (e.g. colors)

Related issue: #789

[mtennekes]

Yesterday, I've reset the crs of land to 4326. It also was that crs, but with a different specification.
Now it the warping works (although I'm not sure if that was the cause). So please check.

I don't recall the exact arguments why raster.wrap has been dropped (have to look up), but I guess it is superfluous because warping is always preferable, and as fallback, a transformation is applied.

[Nowosad]

The issue is still there. I would not have thought that sf::sf_use_s2 impacts st_warp, but it seems to be the case (see the reprex below).

@edzer -- is this expected?

library(tmap)
data("land")

elev = land[4]
tm_shape(elev) +
  tm_raster()

tm_shape(elev, crs = "EPSG:8857") +
  tm_raster()
#> Warning: Unable to warp stars. Stars will be transformed now (which will take
#> some time).

library(sf)
#> Linking to GEOS 3.12.2, GDAL 3.9.3, PROJ 9.4.1; sf_use_s2() is TRUE
library(stars)
#> Loading required package: abind

# works (to curvilinear)
elev2 = st_transform(elev, "EPSG:8857")

# fails
elev3 = st_warp(elev, crs = "EPSG:8857")
#> Error: argument dfMaxLength should be positive

# works
sf_use_s2(FALSE)
#> Spherical geometry (s2) switched off
elev3 = st_warp(elev, crs = "EPSG:8857")