[SPARK-3854][BUILD] Scala style: require spaces before `{`.

## What changes were proposed in this pull request?

Since the opening curly brace, '{', has many usages as discussed in [SPARK-3854](https://issues.apache.org/jira/browse/SPARK-3854), this PR adds a ScalaStyle rule to prevent '){' pattern  for the following majority pattern and fixes the code accordingly. If we enforce this in ScalaStyle from now, it will improve the Scala code quality and reduce review time.
```
// Correct:
if (true) {
  println("Wow!")
}

// Incorrect:
if (true){
   println("Wow!")
}
```
IntelliJ also shows new warnings based on this.

## How was this patch tested?

Pass the Jenkins ScalaStyle test.

Author: Dongjoon Hyun <dongjoon@apache.org>

Closes #11637 from dongjoon-hyun/SPARK-3854.

9 files changed, 9 insertions, 9 deletions

diff --git a/core/src/main/scala/org/apache/spark/rdd/RDD.scala b/core/src/main/scala/org/apache/spark/rdd/RDD.scala
index 8bf4489e1a..8782fcda16 100644
--- a/core/src/main/scala/org/apache/spark/rdd/RDD.scala
+++ b/core/src/main/scala/org/apache/spark/rdd/RDD.scala
@@ -722,7 +722,7 @@ abstract class RDD[T: ClassTag](
    *                        An example of pipe the RDD data of groupBy() in a streaming way,
    *                        instead of constructing a huge String to concat all the elements:
    *                        def printRDDElement(record:(String, Seq[String]), f:String=>Unit) =
-   *                          for (e <- record._2){f(e)}
+   *                          for (e <- record._2) {f(e)}
    * @param separateWorkingDir Use separate working directories for each task.
    * @return the result RDD
    */
diff --git a/core/src/main/scala/org/apache/spark/rpc/RpcTimeout.scala b/core/src/main/scala/org/apache/spark/rpc/RpcTimeout.scala
index 8b4ebf34ba..2950df62bf 100644
--- a/core/src/main/scala/org/apache/spark/rpc/RpcTimeout.scala
+++ b/core/src/main/scala/org/apache/spark/rpc/RpcTimeout.scala
@@ -119,7 +119,7 @@ private[spark] object RpcTimeout {
     // Find the first set property or use the default value with the first property
     val itr = timeoutPropList.iterator
     var foundProp: Option[(String, String)] = None
-    while (itr.hasNext && foundProp.isEmpty){
+    while (itr.hasNext && foundProp.isEmpty) {
       val propKey = itr.next()
       conf.getOption(propKey).foreach { prop => foundProp = Some(propKey, prop) }
     }
diff --git a/core/src/main/scala/org/apache/spark/scheduler/InputFormatInfo.scala b/core/src/main/scala/org/apache/spark/scheduler/InputFormatInfo.scala
index 8235b10245..def0aac720 100644
--- a/core/src/main/scala/org/apache/spark/scheduler/InputFormatInfo.scala
+++ b/core/src/main/scala/org/apache/spark/scheduler/InputFormatInfo.scala
@@ -173,7 +173,7 @@ object InputFormatInfo {
     for (inputSplit <- formats) {
       val splits = inputSplit.findPreferredLocations()
 
-      for (split <- splits){
+      for (split <- splits) {
         val location = split.hostLocation
         val set = nodeToSplit.getOrElseUpdate(location, new HashSet[SplitInfo])
         set += split
diff --git a/core/src/main/scala/org/apache/spark/scheduler/TaskSchedulerImpl.scala b/core/src/main/scala/org/apache/spark/scheduler/TaskSchedulerImpl.scala
index 8b2f4973ef..36df032c25 100644
--- a/core/src/main/scala/org/apache/spark/scheduler/TaskSchedulerImpl.scala
+++ b/core/src/main/scala/org/apache/spark/scheduler/TaskSchedulerImpl.scala
@@ -623,7 +623,7 @@ private[spark] object TaskSchedulerImpl {
         val containerList: ArrayBuffer[T] = map.getOrElse(key, null)
         assert(containerList != null)
         // Get the index'th entry for this host - if present
-        if (index < containerList.size){
+        if (index < containerList.size) {
           retval += containerList.apply(index)
           found = true
         }
diff --git a/core/src/main/scala/org/apache/spark/status/api/v1/OneStageResource.scala b/core/src/main/scala/org/apache/spark/status/api/v1/OneStageResource.scala
index f9812f06cf..3e6d2942d0 100644
--- a/core/src/main/scala/org/apache/spark/status/api/v1/OneStageResource.scala
+++ b/core/src/main/scala/org/apache/spark/status/api/v1/OneStageResource.scala
@@ -33,7 +33,7 @@ private[v1] class OneStageResource(ui: SparkUI) {
   @GET
   @Path("")
   def stageData(@PathParam("stageId") stageId: Int): Seq[StageData] = {
-    withStage(stageId){ stageAttempts =>
+    withStage(stageId) { stageAttempts =>
       stageAttempts.map { stage =>
         AllStagesResource.stageUiToStageData(stage.status, stage.info, stage.ui,
           includeDetails = true)
diff --git a/core/src/main/scala/org/apache/spark/storage/BlockManagerId.scala b/core/src/main/scala/org/apache/spark/storage/BlockManagerId.scala
index 69ac37511e..cae7c9ed95 100644
--- a/core/src/main/scala/org/apache/spark/storage/BlockManagerId.scala
+++ b/core/src/main/scala/org/apache/spark/storage/BlockManagerId.scala
@@ -44,7 +44,7 @@ class BlockManagerId private (
 
   def executorId: String = executorId_
 
-  if (null != host_){
+  if (null != host_) {
     Utils.checkHost(host_, "Expected hostname")
     assert (port_ > 0)
   }
diff --git a/core/src/test/scala/org/apache/spark/AccumulatorSuite.scala b/core/src/test/scala/org/apache/spark/AccumulatorSuite.scala
index 4ff8ae57ab..61ab24051e 100644
--- a/core/src/test/scala/org/apache/spark/AccumulatorSuite.scala
+++ b/core/src/test/scala/org/apache/spark/AccumulatorSuite.scala
@@ -57,7 +57,7 @@ class AccumulatorSuite extends SparkFunSuite with Matchers with LocalSparkContex
       }
     }
 
-  test ("basic accumulation"){
+  test ("basic accumulation") {
     sc = new SparkContext("local", "test")
     val acc : Accumulator[Int] = sc.accumulator(0)
 
diff --git a/core/src/test/scala/org/apache/spark/ImplicitOrderingSuite.scala b/core/src/test/scala/org/apache/spark/ImplicitOrderingSuite.scala
index 4399f25626..939f12f94f 100644
--- a/core/src/test/scala/org/apache/spark/ImplicitOrderingSuite.scala
+++ b/core/src/test/scala/org/apache/spark/ImplicitOrderingSuite.scala
@@ -21,7 +21,7 @@ import org.apache.spark.rdd.RDD
 
 class ImplicitOrderingSuite extends SparkFunSuite with LocalSparkContext {
   // Tests that PairRDDFunctions grabs an implicit Ordering in various cases where it should.
-  test("basic inference of Orderings"){
+  test("basic inference of Orderings") {
     sc = new SparkContext("local", "test")
     val rdd = sc.parallelize(1 to 10)
 
diff --git a/core/src/test/scala/org/apache/spark/deploy/history/ApplicationCacheSuite.scala b/core/src/test/scala/org/apache/spark/deploy/history/ApplicationCacheSuite.scala
index de6680c610..e24188781f 100644
--- a/core/src/test/scala/org/apache/spark/deploy/history/ApplicationCacheSuite.scala
+++ b/core/src/test/scala/org/apache/spark/deploy/history/ApplicationCacheSuite.scala
@@ -476,7 +476,7 @@ class ApplicationCacheSuite extends SparkFunSuite with Logging with MockitoSugar
     when(request.getRequestURI()).thenReturn("http://localhost:18080/history/local-123/jobs/job/")
     when(request.getQueryString()).thenReturn("id=2")
     val resp = mock[HttpServletResponse]
-    when(resp.encodeRedirectURL(any())).thenAnswer(new Answer[String](){
+    when(resp.encodeRedirectURL(any())).thenAnswer(new Answer[String]() {
       override def answer(invocationOnMock: InvocationOnMock): String = {
         invocationOnMock.getArguments()(0).asInstanceOf[String]
       }