Revert "[SPARK-27278][SQL] Optimize GetMapValue when the map is a foldable and the key is not"

This reverts commit 5888b15.

Author: dongjoon-hyun

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

@@ -17,13 +17,9 @@
 
 package org.apache.spark.sql.catalyst.optimizer
 
-import scala.collection.mutable
-
 import org.apache.spark.sql.catalyst.expressions._
 import org.apache.spark.sql.catalyst.plans.logical.{Aggregate, LogicalPlan}
 import org.apache.spark.sql.catalyst.rules.Rule
-import org.apache.spark.sql.catalyst.util.MapData
-import org.apache.spark.sql.types.MapType
 
 /**
  * Simplify redundant [[CreateNamedStructLike]], [[CreateArray]] and [[CreateMap]] expressions.
@@ -63,16 +59,6 @@ object SimplifyExtractValueOps extends Rule[LogicalPlan] {
           Literal(null, ga.dataType)
         }
       case GetMapValue(CreateMap(elems), key) => CaseKeyWhen(key, elems)
-      // The case below happens when the map is foldable, but the key is not, so ConstantFolding
-      // converts the map in a Literal, but the GetMapValue is still there since the key is not
-      // foldable. It cannot happen in any other case.
-      case GetMapValue(Literal(map: MapData, MapType(kt, vt, _)), key) if !key.foldable =>
-        val elems = new mutable.ListBuffer[Literal]
-        map.foreach(kt, vt, (key, value) => {
-          elems.append(Literal(key, kt))
-          elems.append(Literal(value, vt))
-        })
-        CaseKeyWhen(key, elems.result())
     }
   }
 }

sql/catalyst/src/test/scala/org/apache/spark/sql/catalyst/optimizer/complexTypesSuite.scala

@@ -452,15 +452,4 @@ class ComplexTypesSuite extends PlanTest with ExpressionEvalHelper {
     checkEvaluation(GetMapValue(mb0, Literal(Array[Byte](2, 1), BinaryType)), "2")
     checkEvaluation(GetMapValue(mb0, Literal(Array[Byte](3, 4))), null)
   }
-
-  test("SPARK-27278: simplify map access with non-foldable key and foldable map") {
-    val query = relation.select(GetMapValue(CreateMap(Seq(
-      1L, "a",
-      2L, "b")), 'id) as "a")
-    val expected = relation.select(
-        CaseWhen(Seq(
-          (EqualTo('id, 1L), "a"),
-          (EqualTo('id, 2L), "b"))) as "a")
-    checkRule(query, expected)
-  }
 }