rasterToMatch with no values produces warning in prepInputs and friends

[achubaty]

I don't think there is a reason that RTM needs values in order to get the crs, origin, res etc. from the raster.

From PredictiveEcology/LandR#118

  cPath <- withr::local_tempdir("cache")
  dPath <- withr::local_tempdir("inputs")

  withr::local_options(reproducible.cachePath = cPath)

  withr::local_seed(123)

  SA <- randomStudyArea(size = 10000000)
  RTM <- rast(SA, resolution = 250)
  sppEquiv <- sppEquivalencies_CA
  sppEquivCol <- "KNN"

  sppEquiv <- sppEquiv[KNN %in% c("Pinu_Spp", "Popu_Tre", "Pice_Mar")]

  ## get all available species for 2001
  httr::with_config(config = httr::config(ssl_verifypeer = 0L), {
    speciesLayers <- LandR::loadkNNSpeciesLayers(
      dPath = dPath,
      rasterToMatch = RTM,
      studyArea = SA,
      year = 2001,
      url = paste0(
        "https://ftp.maps.canada.ca/pub/nrcan_rncan/Forests_Foret/",
        "canada-forests-attributes_attributs-forests-canada/",
        "2001-attributes_attributs-2001/"
      ),
      sppEquiv = sppEquiv,
      sppEquivCol = sppEquivCol,
      thresh = 0
    )
  })
  ## WARNING: [readValues] raster has no values

[eliotmcintire]

Turns out this is a terra::wrap issue. This is used inside .wrap so that it can be saved to disk.

terra::wrap(object)
Error: (converted from warning) [readValues] raster has no values

Does a user want this warning suppressed because they don't really care about this during a digest?

[achubaty]

if it's spurious, then it should be suppressed

[eliotmcintire]

It isn't spurious. It is a terra warning. In this case it is inside a Cache, so it is debatable that the user cares.