diff --git a/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/expressions/AttributeSet.scala b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/expressions/AttributeSet.scala
index 4b1185d7cb75f..957d1608ec80d 100644
--- a/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/expressions/AttributeSet.scala
+++ b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/expressions/AttributeSet.scala
@@ -113,5 +113,5 @@ class AttributeSet private (val baseSet: Set[AttributeEquals])
 
   override def toString = "{" + baseSet.map(_.a).mkString(", ") + "}"
 
-	def isEmpty: Boolean = baseSet.isEmpty
+  def isEmpty: Boolean = baseSet.isEmpty
 }