[SPARKR-244] Fix test failure after integration of subtract() and subtractByKey() for RDD.

Author: Sun Rui

R/pkg/NAMESPACE

@@ -122,6 +122,7 @@ exportMethods("columns",
               "show",
               "showDF",
               "sortDF",
+              "except",
               "toJSON",
               "toRDD",
               "unionAll",

R/pkg/R/DataFrame.R

@@ -1141,32 +1141,33 @@ setMethod("intersect",
             dataFrame(intersected)
           })
 
-#' Subtract
+#' except
 #'
 #' Return a new DataFrame containing rows in this DataFrame
 #' but not in another DataFrame. This is equivalent to `EXCEPT` in SQL.
 #'
 #' @param x A Spark DataFrame
 #' @param y A Spark DataFrame
-#' @return A DataFrame containing the result of the subtract operation.
-#' @rdname subtract
+#' @return A DataFrame containing the result of the except operation.
+#' @rdname except
 #' @export
 #' @examples
 #'\dontrun{
 #' sc <- sparkR.init()
 #' sqlCtx <- sparkRSQL.init(sc)
 #' df1 <- jsonFile(sqlCtx, path)
 #' df2 <- jsonFile(sqlCtx, path2)
-#' subtractDF <- subtract(df, df2)
+#' exceptDF <- except(df, df2)
 #' }
+setGeneric("except", function(x, y) { standardGeneric("except") })
 
-#' @rdname subtract
+#' @rdname except
 #' @export
-setMethod("subtract",
-          signature(x = "DataFrame", other = "DataFrame"),
-          function(x, other) {
-            subtracted <- callJMethod(x@sdf, "except", other@sdf)
-            dataFrame(subtracted)
+setMethod("except",
+          signature(x = "DataFrame", y = "DataFrame"),
+          function(x, y) {
+            excepted <- callJMethod(x@sdf, "except", y@sdf)
+            dataFrame(excepted)
           })
 
 #' Save the contents of the DataFrame to a data source

R/pkg/inst/tests/test_sparkSQL.R

@@ -644,7 +644,7 @@ test_that("isLocal()", {
   expect_false(isLocal(df))
 })
 
-test_that("unionAll(), subtract(), and intersect() on a DataFrame", {
+test_that("unionAll(), except(), and intersect() on a DataFrame", {
   df <- jsonFile(sqlCtx, jsonPath)
 
   lines <- c("{\"name\":\"Bob\", \"age\":24}",
@@ -659,10 +659,10 @@ test_that("unionAll(), subtract(), and intersect() on a DataFrame", {
   expect_true(count(unioned) == 6)
   expect_true(first(unioned)$name == "Michael")
 
-  subtracted <- sortDF(subtract(df, df2), desc(df$age))
+  excepted <- sortDF(except(df, df2), desc(df$age))
   expect_true(inherits(unioned, "DataFrame"))
-  expect_true(count(subtracted) == 2)
-  expect_true(first(subtracted)$name == "Justin")
+  expect_true(count(excepted) == 2)
+  expect_true(first(excepted)$name == "Justin")
 
   intersected <- sortDF(intersect(df, df2), df$age)
   expect_true(inherits(unioned, "DataFrame"))