Fix tests

Author: Andrew Or

sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/catalog/SessionCatalog.scala

@@ -24,7 +24,7 @@ import scala.collection.JavaConverters._
 import org.apache.spark.sql.AnalysisException
 import org.apache.spark.sql.catalyst.{CatalystConf, SimpleCatalystConf}
 import org.apache.spark.sql.catalyst.{FunctionIdentifier, TableIdentifier}
-import org.apache.spark.sql.catalyst.analysis.{EmptyFunctionRegistry, FunctionRegistry}
+import org.apache.spark.sql.catalyst.analysis.{FunctionRegistry, SimpleFunctionRegistry}
 import org.apache.spark.sql.catalyst.analysis.FunctionRegistry.FunctionBuilder
 import org.apache.spark.sql.catalyst.expressions.{Expression, ExpressionInfo}
 import org.apache.spark.sql.catalyst.plans.logical.{LogicalPlan, SubqueryAlias}
@@ -47,7 +47,7 @@ class SessionCatalog(
 
   // For testing only.
   def this(externalCatalog: ExternalCatalog) {
-    this(externalCatalog, EmptyFunctionRegistry)
+    this(externalCatalog, new SimpleFunctionRegistry)
   }
 
   protected[this] val tempTables = new ConcurrentHashMap[String, LogicalPlan]

sql/catalyst/src/test/scala/org/apache/spark/sql/catalyst/catalog/SessionCatalogSuite.scala

@@ -821,7 +821,7 @@ class SessionCatalogSuite extends SparkFunSuite {
     // If no database is specified, we'll first rename temporary functions
     sessionCatalog.createFunction(newFunc("func1", Some("db2")))
     sessionCatalog.renameFunction(FunctionIdentifier("func1"), FunctionIdentifier("func4"))
-    assert(sessionCatalog.getTempFunction("func4") == tempFunc)
+    assert(sessionCatalog.getTempFunction("func4") == Some(tempFunc))
     assert(sessionCatalog.getTempFunction("func1") == None)
     assert(externalCatalog.listFunctions("db2", "*").toSet == Set("func1", "func3"))
     // Then, if no such temporary function exist, rename the function in the current database