Running examples in 'reproducible-Ex.R' failed
The error most likely occurred in:

> ### Name: cropInputs
> ### Title: Crop a 'Spatial*' or 'Raster*' object
> ### Aliases: cropInputs cropInputs.default cropInputs.spatialClasses
> ###   cropInputs.sf
> 
> ### ** Examples
> 
> # Add a study area to Crop and Mask to
> # Create a "study area"
> library(sp)
> library(raster)
> ow <- setwd(tempdir())
> 
> # make a SpatialPolygon
> coords1 <- structure(c(-123.98, -117.1, -80.2, -100, -123.98, 60.9, 67.73, 65.58, 51.79, 60.9),
+                      .Dim = c(5L, 2L))
> Sr1 <- Polygon(coords1)
> Srs1 <- Polygons(list(Sr1), "s1")
> shpEcozone <- SpatialPolygons(list(Srs1), 1L)
> crs(shpEcozone) <- "+proj=longlat +datum=WGS84 +no_defs +ellps=WGS84 +towgs84=0,0,0"
> 
> # make a "study area" that is subset of larger dataset
> coords <- structure(c(-118.98, -116.1, -99.2, -106, -118.98, 59.9, 65.73, 63.58, 54.79, 59.9),
+                     .Dim = c(5L, 2L))
> Sr1 <- Polygon(coords)
> Srs1 <- Polygons(list(Sr1), "s1")
> StudyArea <- SpatialPolygons(list(Srs1), 1L)
> crs(StudyArea) <- "+proj=longlat +datum=WGS84 +no_defs +ellps=WGS84 +towgs84=0,0,0"
> 
> ##########
> shpEcozonePostProcessed <- postProcess(shpEcozone, studyArea = StudyArea)
useCache is FALSE; skipping Cache on function cropInputs)
    cropping ...
Error in loadNamespace(x) : there is no package called 'sf'
Checking for errors in SpatialPolygon
please install sf package to evaluate whether there are errors in the polygons object: install.packages('sf')
  useCache is FALSE; skipping Cache on function buffer (currently running nested Cache level 2)
  Some or all of the errors fixed.
Error in loadNamespace(x) : there is no package called 'sf'
Checking for errors in SpatialPolygon
please install sf package to evaluate whether there are errors in the polygons object: install.packages('sf')
  useCache is FALSE; skipping Cache on function buffer (currently running nested Cache level 2)
  Some or all of the errors fixed.
Error in loadNamespace(x) : there is no package called 'sf'
Checking for errors in SpatialPolygon
please install sf package to evaluate whether there are errors in the polygons object: install.packages('sf')
  useCache is FALSE; skipping Cache on function buffer (currently running nested Cache level 2)
  Some or all of the errors fixed.
Error in loadNamespace(x) : there is no package called 'sf'
Checking for errors in SpatialPolygon
please install sf package to evaluate whether there are errors in the polygons object: install.packages('sf')
  useCache is FALSE; skipping Cache on function buffer (currently running nested Cache level 2)
  Some or all of the errors fixed.
Error in loadNamespace(x) : there is no package called 'sf'
Calls: postProcess ... loadNamespace -> withRestarts -> withOneRestart -> doWithOneRestart
Execution halted