Fixed 'datasource' test

Author: StuartWheater

R/ds.scatterPlot.R

@@ -133,11 +133,6 @@ ds.scatterPlot <- function (x=NULL, y=NULL, method='deterministic', k=3, noise=0
     stop("Please provide the name of the x-variable", call.=FALSE)
   }
 
-  # ensure datasources is a list of DSConnection-class
-  if(!(is.list(datasources) && all(unlist(lapply(datasources, function(d) {methods::is(d,"DSConnection")}))))){
-    stop("The 'datasources' were expected to be a list of DSConnection-class objects", call.=FALSE)
-  }
-
   if(is.null(y)){
     stop("Please provide the name of the y-variable", call.=FALSE)
   }
@@ -147,6 +142,11 @@ ds.scatterPlot <- function (x=NULL, y=NULL, method='deterministic', k=3, noise=0
     datasources <- datashield.connections_find()
   }
 
+  # ensure datasources is a list of DSConnection-class
+  if(!(is.list(datasources) && all(unlist(lapply(datasources, function(d) {methods::is(d,"DSConnection")}))))){
+    stop("The 'datasources' were expected to be a list of DSConnection-class objects", call.=FALSE)
+  }
+
   # the input variable might be given as column table (i.e. D$object)
   # or just as a vector not attached to a table (i.e. object)
   # we have to make sure the function deals with each case