[SPARK-6765] Enable scalastyle on test code.

Turn scalastyle on for all test code. Most of the violations have been resolved in my previous pull requests:

Core: https://github.com/apache/spark/pull/5484
SQL: https://github.com/apache/spark/pull/5412
MLlib: https://github.com/apache/spark/pull/5411
GraphX: https://github.com/apache/spark/pull/5410
Streaming: https://github.com/apache/spark/pull/5409

Author: Reynold Xin <rxin@databricks.com>

Closes #5486 from rxin/test-style-enable and squashes the following commits:

01683de [Reynold Xin] Fixed new code.
a4ab46e [Reynold Xin] Fixed tests.
20adbc8 [Reynold Xin] Missed one violation.
5e36521 [Reynold Xin] [SPARK-6765] Enable scalastyle on test code.

3 files changed, 18 insertions, 9 deletions

diff --git a/yarn/src/test/scala/org/apache/spark/deploy/yarn/ClientSuite.scala b/yarn/src/test/scala/org/apache/spark/deploy/yarn/ClientSuite.scala
index 92f04b4b85..c1b94ac9c5 100644
--- a/yarn/src/test/scala/org/apache/spark/deploy/yarn/ClientSuite.scala
+++ b/yarn/src/test/scala/org/apache/spark/deploy/yarn/ClientSuite.scala
@@ -232,19 +232,26 @@ class ClientSuite extends FunSuite with Matchers with BeforeAndAfterAll {
     testCode(conf)
   }
 
-  def newEnv = MutableHashMap[String, String]()
+  def newEnv: MutableHashMap[String, String] = MutableHashMap[String, String]()
 
-  def classpath(env: MutableHashMap[String, String]) = env(Environment.CLASSPATH.name).split(":|;|<CPS>")
+  def classpath(env: MutableHashMap[String, String]): Array[String] =
+    env(Environment.CLASSPATH.name).split(":|;|<CPS>")
 
-  def flatten(a: Option[Seq[String]], b: Option[Seq[String]]) = (a ++ b).flatten.toArray
+  def flatten(a: Option[Seq[String]], b: Option[Seq[String]]): Array[String] =
+    (a ++ b).flatten.toArray
 
-  def getFieldValue[A, B](clazz: Class[_], field: String, defaults: => B)(mapTo: A => B): B =
-    Try(clazz.getField(field)).map(_.get(null).asInstanceOf[A]).toOption.map(mapTo).getOrElse(defaults)
+  def getFieldValue[A, B](clazz: Class[_], field: String, defaults: => B)(mapTo: A => B): B = {
+    Try(clazz.getField(field))
+      .map(_.get(null).asInstanceOf[A])
+      .toOption
+      .map(mapTo)
+      .getOrElse(defaults)
+  }
 
   def getFieldValue2[A: ClassTag, A1: ClassTag, B](
         clazz: Class[_],
         field: String,
-        defaults: => B)(mapTo:  A => B)(mapTo1: A1 => B) : B = {
+        defaults: => B)(mapTo:  A => B)(mapTo1: A1 => B): B = {
     Try(clazz.getField(field)).map(_.get(null)).map {
       case v: A => mapTo(v)
       case v1: A1 => mapTo1(v1)
diff --git a/yarn/src/test/scala/org/apache/spark/deploy/yarn/YarnAllocatorSuite.scala b/yarn/src/test/scala/org/apache/spark/deploy/yarn/YarnAllocatorSuite.scala
index c09b01bafc..455f1019d8 100644
--- a/yarn/src/test/scala/org/apache/spark/deploy/yarn/YarnAllocatorSuite.scala
+++ b/yarn/src/test/scala/org/apache/spark/deploy/yarn/YarnAllocatorSuite.scala
@@ -79,7 +79,7 @@ class YarnAllocatorSuite extends FunSuite with Matchers with BeforeAndAfterEach
   }
 
   class MockSplitInfo(host: String) extends SplitInfo(null, host, null, 1, null) {
-    override def equals(other: Any) = false
+    override def equals(other: Any): Boolean = false
   }
 
   def createAllocator(maxExecutors: Int = 5): YarnAllocator = {
@@ -118,7 +118,9 @@ class YarnAllocatorSuite extends FunSuite with Matchers with BeforeAndAfterEach
     handler.getNumExecutorsRunning should be (1)
     handler.allocatedContainerToHostMap.get(container.getId).get should be ("host1")
     handler.allocatedHostToContainersMap.get("host1").get should contain (container.getId)
-    rmClient.getMatchingRequests(container.getPriority, "host1", containerResource).size should be (0)
+
+    val size = rmClient.getMatchingRequests(container.getPriority, "host1", containerResource).size
+    size should be (0)
   }
 
   test("some containers allocated") {
diff --git a/yarn/src/test/scala/org/apache/spark/deploy/yarn/YarnSparkHadoopUtilSuite.scala b/yarn/src/test/scala/org/apache/spark/deploy/yarn/YarnSparkHadoopUtilSuite.scala
index 4194f36499..9395316b71 100644
--- a/yarn/src/test/scala/org/apache/spark/deploy/yarn/YarnSparkHadoopUtilSuite.scala
+++ b/yarn/src/test/scala/org/apache/spark/deploy/yarn/YarnSparkHadoopUtilSuite.scala
@@ -46,7 +46,7 @@ class YarnSparkHadoopUtilSuite extends FunSuite with Matchers with Logging {
     logWarning("Cannot execute bash, skipping bash tests.")
   }
 
-  def bashTest(name: String)(fn: => Unit) =
+  def bashTest(name: String)(fn: => Unit): Unit =
     if (hasBash) test(name)(fn) else ignore(name)(fn)
 
   bashTest("shell script escaping") {