[SPARK-19828][R][FOLLOWUP] Rename asJsonArray to as.json.array in fro…

…m_json function in R

## What changes were proposed in this pull request?

This was suggested to be `as.json.array` at the first place in the PR to SPARK-19828 but we could not do this as the lint check emits an error for multiple dots in the variable names.

After SPARK-20278, now we are able to use `multiple.dots.in.names`. `asJsonArray` in `from_json` function is still able to be changed as 2.2 is not released yet.

So, this PR proposes to rename `asJsonArray` to `as.json.array`.

## How was this patch tested?

Jenkins tests, local tests with `./R/run-tests.sh` and manual `./dev/lint-r`. Existing tests should cover this.

Author: hyukjinkwon <[email protected]>

Closes apache#17653 from HyukjinKwon/SPARK-19828-followup.

R/pkg/R/functions.R

@@ -2438,12 +2438,12 @@ setMethod("date_format", signature(y = "Column", x = "character"),
 #' from_json
 #'
 #' Parses a column containing a JSON string into a Column of \code{structType} with the specified
-#' \code{schema} or array of \code{structType} if \code{asJsonArray} is set to \code{TRUE}.
+#' \code{schema} or array of \code{structType} if \code{as.json.array} is set to \code{TRUE}.
 #' If the string is unparseable, the Column will contains the value NA.
 #'
 #' @param x Column containing the JSON string.
 #' @param schema a structType object to use as the schema to use when parsing the JSON string.
-#' @param asJsonArray indicating if input string is JSON array of objects or a single object.
+#' @param as.json.array indicating if input string is JSON array of objects or a single object.
 #' @param ... additional named properties to control how the json is parsed, accepts the same
 #'            options as the JSON data source.
 #'
@@ -2459,8 +2459,8 @@ setMethod("date_format", signature(y = "Column", x = "character"),
 #'}
 #' @note from_json since 2.2.0
 setMethod("from_json", signature(x = "Column", schema = "structType"),
-          function(x, schema, asJsonArray = FALSE, ...) {
-            if (asJsonArray) {
+          function(x, schema, as.json.array = FALSE, ...) {
+            if (as.json.array) {
               jschema <- callJStatic("org.apache.spark.sql.types.DataTypes",
                                      "createArrayType",
                                      schema$jobj)

R/pkg/inst/tests/testthat/test_sparkSQL.R

@@ -1454,7 +1454,7 @@ test_that("column functions", {
   jsonArr <- "[{\"name\":\"Bob\"}, {\"name\":\"Alice\"}]"
   df <- as.DataFrame(list(list("people" = jsonArr)))
   schema <- structType(structField("name", "string"))
-  arr <- collect(select(df, alias(from_json(df$people, schema, asJsonArray = TRUE), "arrcol")))
+  arr <- collect(select(df, alias(from_json(df$people, schema, as.json.array = TRUE), "arrcol")))
   expect_equal(ncol(arr), 1)
   expect_equal(nrow(arr), 1)
   expect_is(arr[[1]][[1]], "list")