fix some code style

Author: root

sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/optimizer/RewriteDistinctAggregates.scala

@@ -115,11 +115,12 @@ object RewriteDistinctAggregates extends Rule[LogicalPlan] {
     }
 
     // Extract distinct aggregate expressions.
-    val distinctAggGroups = aggExpressions.filter(_.isDistinct).groupBy{
+    val distinctAggGroups = aggExpressions.filter(_.isDistinct).groupBy {
       e =>
-        if (e.aggregateFunction.children.exists(!_.foldable)) {
+        val unfoldableChildren = e.aggregateFunction.children.filter(!_.foldable).toSet
+        if (unfoldableChildren.nonEmpty) {
           // Only expand the unfoldable children
-          e.aggregateFunction.children.filter(!_.foldable).toSet
+          unfoldableChildren
         } else {
           // If aggregateFunction's children are all foldable
           // we must expand at least one of the children (here we take the first child),

sql/hive/src/test/scala/org/apache/spark/sql/hive/execution/HiveUDFSuite.scala

@@ -150,21 +150,38 @@ class HiveUDFSuite extends QueryTest with TestHiveSingleton with SQLTestUtils {
   }
 
   test("Generic UDAF aggregates") {
-    checkAnswer(sql("SELECT percentile_approx(2, 0.99999), " +
-      "sum(distinct 1), count(distinct 1,2,3,4) FROM src LIMIT 1"),
-      sql("SELECT 2, 1, 1 FROM src LIMIT 1")
-        .collect().toSeq)
 
-    checkAnswer(sql("SELECT ceiling(percentile_approx(distinct key, 0.99999))" +
-      ", count(distinct key), sum(distinct key), " +
-      "count(distinct 1), sum(distinct 1), sum(1) FROM src LIMIT 1"),
-            sql("SELECT max(key), count(distinct key), sum(distinct key)," +
-              " 1, 1, sum(1) FROM src LIMIT 1")
-              .collect().toSeq)
+    checkAnswer(sql(
+     """
+       |SELECT percentile_approx(2, 0.99999),
+       |       sum(distinct 1),
+       |       count(distinct 1,2,3,4) FROM src LIMIT 1
+     """.stripMargin), sql("SELECT 2, 1, 1 FROM src LIMIT 1").collect().toSeq)
+
+    checkAnswer(sql(
+      """
+        |SELECT ceiling(percentile_approx(distinct key, 0.99999)),
+        |       count(distinct key),
+        |       sum(distinct key),
+        |       count(distinct 1),
+        |       sum(distinct 1),
+        |       sum(1) FROM src LIMIT 1
+      """.stripMargin),
+      sql(
+        """
+          |SELECT max(key),
+          |       count(distinct key),
+          |       sum(distinct key),
+          |       1, 1, sum(1) FROM src LIMIT 1
+        """.stripMargin).collect().toSeq)
 
-    checkAnswer(sql("SELECT ceiling(percentile_approx(distinct key, 0.9 + 0.09999))" +
-      ", count(distinct key), sum(distinct key), " +
-      "count(distinct 1), sum(distinct 1), sum(1) FROM src LIMIT 1"),
+    checkAnswer(sql(
+      """
+        |SELECT ceiling(percentile_approx(distinct key, 0.9 + 0.09999)),
+        |       count(distinct key), sum(distinct key),
+        |       count(distinct 1), sum(distinct 1),
+        |       sum(1) FROM src LIMIT 1
+      """.stripMargin),
       sql("SELECT max(key), count(distinct key), sum(distinct key), 1, 1, sum(1) FROM src LIMIT 1")
         .collect().toSeq)