Replaces TestHiveContext.configure() with HiveContext.overrideHiveConf()

This change is per @marmbrus's comment in PR apache#3895.

sql/hive/src/main/scala/org/apache/spark/sql/hive/HiveContext.scala

@@ -225,7 +225,7 @@ class HiveContext(sc: SparkContext) extends SQLContext(sc) {
   @transient protected[hive] lazy val sessionState: SessionState = {
     var state = SessionState.get()
     if (state == null) {
-      state = new SessionState(new HiveConf(classOf[SessionState]))
+      state = new SessionState(overrideHiveConf(new HiveConf(classOf[SessionState])))
       SessionState.start(state)
     }
     if (state.out == null) {
@@ -242,6 +242,9 @@ class HiveContext(sc: SparkContext) extends SQLContext(sc) {
     sessionState.getConf
   }
 
+  // Sub-classes of HiveContext for testing purposes can override Hive configurations here.
+  protected def overrideHiveConf(conf: HiveConf): HiveConf = conf
+
   override def setConf(key: String, value: String): Unit = {
     super.setConf(key, value)
     runSqlHive(s"SET $key=$value")

sql/hive/src/main/scala/org/apache/spark/sql/hive/test/TestHive.scala

@@ -20,6 +20,7 @@ package org.apache.spark.sql.hive.test
 import java.io.File
 import java.util.{Set => JavaSet}
 
+import org.apache.hadoop.hive.conf.HiveConf
 import org.apache.hadoop.hive.ql.exec.FunctionRegistry
 import org.apache.hadoop.hive.ql.io.avro.{AvroContainerInputFormat, AvroContainerOutputFormat}
 import org.apache.hadoop.hive.ql.metadata.Table
@@ -73,12 +74,19 @@ class TestHiveContext(sc: SparkContext) extends HiveContext(sc) {
   lazy val metastorePath = getTempFilePath("sparkHiveMetastore").getCanonicalPath
 
   /** Sets up the system initially or after a RESET command */
-  protected def configure(): Unit = {
-    setConf("javax.jdo.option.ConnectionURL",
+  override protected def overrideHiveConf(conf: HiveConf): HiveConf = {
+    conf.set(
+      "javax.jdo.option.ConnectionURL",
       s"jdbc:derby:;databaseName=$metastorePath;create=true")
-    setConf("hive.metastore.warehouse.dir", warehousePath)
+
+    conf.set(
+      "hive.metastore.warehouse.dir",
+      warehousePath)
+
     Utils.registerShutdownDeleteDir(new File(warehousePath))
     Utils.registerShutdownDeleteDir(new File(metastorePath))
+
+    conf
   }
 
   val testTempDir = File.createTempFile("testTempFiles", "spark.hive.tmp")
@@ -89,8 +97,6 @@ class TestHiveContext(sc: SparkContext) extends HiveContext(sc) {
   // For some hive test case which contain ${system:test.tmp.dir}
   System.setProperty("test.tmp.dir", testTempDir.getCanonicalPath)
 
-  configure() // Must be called before initializing the catalog below.
-
   /** The location of the compiled hive distribution */
   lazy val hiveHome = envVarToFile("HIVE_HOME")
   /** The location of the hive source code. */
@@ -383,9 +389,6 @@ class TestHiveContext(sc: SparkContext) extends HiveContext(sc) {
    */
   protected val originalUdfs: JavaSet[String] = FunctionRegistry.getFunctionNames
 
-  // Database default may not exist in 0.13.1, create it if not exist
-  HiveShim.createDefaultDBIfNeeded(this)
-
   /**
    * Resets the test instance by deleting any tables that have been created.
    * TODO: also clear out UDFs, views, etc.
@@ -436,7 +439,6 @@ class TestHiveContext(sc: SparkContext) extends HiveContext(sc) {
       runSqlHive("set datanucleus.cache.collections.lazy=true")
       // Lots of tests fail if we do not change the partition whitelist from the default.
       runSqlHive("set hive.metastore.partition.name.whitelist.pattern=.*")
-      configure()
 
       runSqlHive("USE default")
 

sql/hive/v0.12.0/src/main/scala/org/apache/spark/sql/hive/Shim12.scala

@@ -189,8 +189,6 @@ private[hive] object HiveShim {
 
   def getStatsSetupConstRawDataSize = StatsSetupConst.RAW_DATA_SIZE
 
-  def createDefaultDBIfNeeded(context: HiveContext) = {  }
-
   def getCommandProcessor(cmd: Array[String], conf: HiveConf) = {
     CommandProcessorFactory.get(cmd(0), conf)
   }

sql/hive/v0.13.1/src/main/scala/org/apache/spark/sql/hive/Shim13.scala

@@ -51,7 +51,7 @@ import org.apache.spark.sql.types.{Decimal, DecimalType}
 /**
  * This class provides the UDF creation and also the UDF instance serialization and
  * de-serialization cross process boundary.
- * 
+ *
  * Detail discussion can be found at https://github.com/apache/spark/pull/3640
  *
  * @param functionClassName UDF class name
@@ -301,11 +301,6 @@ private[hive] object HiveShim {
 
   def getStatsSetupConstRawDataSize = StatsSetupConst.RAW_DATA_SIZE
 
-  def createDefaultDBIfNeeded(context: HiveContext) = {
-    context.runSqlHive("CREATE DATABASE IF NOT EXISTS default")
-    context.runSqlHive("USE default")
-  }
-
   def getCommandProcessor(cmd: Array[String], conf: HiveConf) = {
     CommandProcessorFactory.get(cmd, conf)
   }
@@ -400,7 +395,7 @@ private[hive] object HiveShim {
       Decimal(hdoi.getPrimitiveJavaObject(data).bigDecimalValue(), hdoi.precision(), hdoi.scale())
     }
   }
- 
+
   /*
    * Bug introduced in hive-0.13. AvroGenericRecordWritable has a member recordReaderID that
    * is needed to initialize before serialization.