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sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/analysis/HiveTypeCoercion.scala

@@ -305,24 +305,18 @@ object HiveTypeCoercion {
 
   /**
    * Convert all expressions in in() list to the left operator type
-   * except when the left operator type is NullType. In case when left hand
-   * operator type is NullType create a Literal(Null).
+   * except when the left operator type is NullType.
    */
   object InConversion extends Rule[LogicalPlan] {
     def apply(plan: LogicalPlan): LogicalPlan = plan resolveExpressions {
       // Skip nodes who's children have not been resolved yet.
       case e if !e.childrenResolved => e
 
-      case i @ In(a, b) if (a.dataType == NullType) =>
-        var inTypes : Seq[DataType] = Seq.empty
-        b.foreach(e => inTypes = inTypes ++ Seq(e.dataType))
-        findWiderCommonType(inTypes) match {
-          case Some(finalDataType) => Literal.create(null, BooleanType)
+      case i @ In(a, b) if b.exists(_.dataType != a.dataType) =>
+        findWiderCommonType(i.children.map(_.dataType)) match {
+          case Some(finalDataType) => i.withNewChildren(i.children.map(Cast(_, finalDataType)))
           case None => i
         }
-
-      case i @ In(a, b) if b.exists(_.dataType != a.dataType) =>
-        i.makeCopy(Array(a, b.map(Cast(_, a.dataType))))
     }
   }
 

sql/catalyst/src/test/scala/org/apache/spark/sql/catalyst/analysis/AnalysisSuite.scala

@@ -154,7 +154,6 @@ class AnalysisSuite extends AnalysisTest {
     val plan = Project(Alias(In(Literal(null), Seq(Literal(true), Literal(1))), "a")() :: Nil,
       LocalRelation()
     )
-    assertAnalysisError(plan, Seq("cannot resolve 'null IN (true,1)' due to data " +
-                                 "type mismatch: Arguments must be same type"))
+    assertAnalysisError(plan, Seq("data type mismatch: Arguments must be same type"))
   }
 }