From 9a1f711db534ca71a8e03353d0aeeeaab8e59703 Mon Sep 17 00:00:00 2001
From: Cheng Lian <lian@databricks.com>
Date: Wed, 29 Jun 2016 16:00:20 +0800
Subject: [PATCH] CheckAnalysis should capture nested aggregate functions that
 reference no input attributes.

---
 .../spark/sql/catalyst/analysis/CheckAnalysis.scala  |  1 -
 .../sql/catalyst/analysis/AnalysisErrorSuite.scala   | 12 +++++++++++-
 .../scala/org/apache/spark/sql/SQLQuerySuite.scala   |  4 +---
 3 files changed, 12 insertions(+), 5 deletions(-)

diff --git a/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/analysis/CheckAnalysis.scala b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/analysis/CheckAnalysis.scala
index ac9693e079f5..7b30fcc6c531 100644
--- a/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/analysis/CheckAnalysis.scala
+++ b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/analysis/CheckAnalysis.scala
@@ -206,7 +206,6 @@ trait CheckAnalysis extends PredicateHelper {
                     "Add to group by or wrap in first() (or first_value) if you don't care " +
                     "which value you get.")
               case e if groupingExprs.exists(_.semanticEquals(e)) => // OK
-              case e if e.references.isEmpty => // OK
               case e => e.children.foreach(checkValidAggregateExpression)
             }
 
diff --git a/sql/catalyst/src/test/scala/org/apache/spark/sql/catalyst/analysis/AnalysisErrorSuite.scala b/sql/catalyst/src/test/scala/org/apache/spark/sql/catalyst/analysis/AnalysisErrorSuite.scala
index a41383fbf656..a9cde1e19efc 100644
--- a/sql/catalyst/src/test/scala/org/apache/spark/sql/catalyst/analysis/AnalysisErrorSuite.scala
+++ b/sql/catalyst/src/test/scala/org/apache/spark/sql/catalyst/analysis/AnalysisErrorSuite.scala
@@ -23,7 +23,7 @@ import org.apache.spark.sql.AnalysisException
 import org.apache.spark.sql.catalyst.dsl.expressions._
 import org.apache.spark.sql.catalyst.dsl.plans._
 import org.apache.spark.sql.catalyst.expressions._
-import org.apache.spark.sql.catalyst.expressions.aggregate.{AggregateExpression, Complete, Count}
+import org.apache.spark.sql.catalyst.expressions.aggregate.{AggregateExpression, Complete, Count, Max}
 import org.apache.spark.sql.catalyst.plans.{Inner, LeftOuter, RightOuter}
 import org.apache.spark.sql.catalyst.plans.logical._
 import org.apache.spark.sql.catalyst.util.{ArrayBasedMapData, GenericArrayData, MapData}
@@ -162,6 +162,16 @@ class AnalysisErrorSuite extends AnalysisTest {
           UnspecifiedFrame)).as('window)),
     "Distinct window functions are not supported" :: Nil)
 
+  errorTest(
+    "nested aggregate functions",
+    testRelation.groupBy('a)(
+      AggregateExpression(
+        Max(AggregateExpression(Count(Literal(1)), Complete, isDistinct = false)),
+        Complete,
+        isDistinct = false)),
+    "not allowed to use an aggregate function in the argument of another aggregate function." :: Nil
+  )
+
   errorTest(
     "offset window function",
     testRelation2.select(
diff --git a/sql/core/src/test/scala/org/apache/spark/sql/SQLQuerySuite.scala b/sql/core/src/test/scala/org/apache/spark/sql/SQLQuerySuite.scala
index b1dbf21d4b80..084ba9b78ec5 100644
--- a/sql/core/src/test/scala/org/apache/spark/sql/SQLQuerySuite.scala
+++ b/sql/core/src/test/scala/org/apache/spark/sql/SQLQuerySuite.scala
@@ -21,10 +21,8 @@ import java.math.MathContext
 import java.sql.Timestamp
 
 import org.apache.spark.AccumulatorSuite
-import org.apache.spark.sql.catalyst.FunctionIdentifier
 import org.apache.spark.sql.catalyst.analysis.UnresolvedException
-import org.apache.spark.sql.catalyst.catalog.{CatalogTestUtils, ExternalCatalog, SessionCatalog}
-import org.apache.spark.sql.catalyst.expressions.{ExpressionDescription, SortOrder}
+import org.apache.spark.sql.catalyst.expressions.SortOrder
 import org.apache.spark.sql.catalyst.plans.logical.Aggregate
 import org.apache.spark.sql.catalyst.util.StringUtils
 import org.apache.spark.sql.execution.aggregate