Move sp to suggests and warn user to install for coordinate searches

DESCRIPTION

@@ -24,7 +24,6 @@ Imports:
     lubridate (>= 1.7.1),
     magrittr (>= 1.5),
     methods (>= 3.2.2),
-    sp (>= 1.2-3),
     stringi (>= 1.1.2),
     tibble (>= 1.2),
     tidyr (>= 0.4.1),
@@ -35,6 +34,7 @@ Suggests:
     ggplot2,
     knitr,
     rmarkdown,
+    sp,
     stringr,
     testthat
 VignetteBuilder: knitr

NEWS.md

@@ -4,6 +4,12 @@ author: "Steffi LaZerte"
 output: html_document
 ---
 
+# weathercan 0.2.3.9000
+
+## Changes
+- `sp` moved to suggests, users are now prompted to install sp if they want to search stations by coordinates
+
+
 # weathercan 0.2.3 (2017-11-22)
 
 ## Changes

R/stations.R

@@ -131,6 +131,9 @@ stations_all <- function(url = NULL,
 #' @param quiet Logical. Suppress all messages (including messages regarding
 #'   missing data, etc.)
 #'
+#' @details To search by coordinates, users must make sure they have the
+#'  \code{\link[sp]{sp}} package installed.
+#'
 #' @return Returns a subset of the stations data frame which match the search
 #'   parameters. If the search was by location, an extra column 'distance' shows
 #'   the distance in kilometres from the location to the station. If no stations
@@ -166,6 +169,11 @@ stations_search <- function(name = NULL,
     if(length(coords) != 2 | all(is.na(coords)) | class(coords) == "try-error") {
       stop("'coord' takes one pair of lat and lon in a numeric vector")
     }
+
+    if(!requireNamespace("sp", quietly = TRUE)) {
+     stop("Package 'sp' required to search for stations using coordinates. Use the code \"install.packages('sp')\" to install.", call. = FALSE)
+    }
+
   }
 
   check_int(interval)