fix tests

Author: Alon Doron

sql/core/src/test/scala/org/apache/spark/sql/DataFrameAggregateSuite.scala

@@ -726,7 +726,7 @@ class DataFrameAggregateSuite extends QueryTest with SharedSQLContext {
 
   test("SPARK-26021: Double and Float 0.0/-0.0 should be equal when grouping") {
     val colName = "i"
-    val doubles = Seq(0.0d, 0.0d, -0.0d).toDF(colName).groupBy(colName).count().collect()
+    val doubles = Seq(0.0d, -0.0d, 0.0d).toDF(colName).groupBy(colName).count().collect()
     val floats = Seq(0.0f, -0.0f, 0.0f).toDF(colName).groupBy(colName).count().collect()
 
     assert(doubles.length == 1)

sql/core/src/test/scala/org/apache/spark/sql/QueryTest.scala

@@ -289,7 +289,7 @@ object QueryTest {
   def prepareRow(row: Row): Row = {
     Row.fromSeq(row.toSeq.map {
       case null => null
-      case d: java.math.BigDecimal => BigDecimal(d)
+      case bd: java.math.BigDecimal => BigDecimal(bd)
       // Equality of WrappedArray differs for AnyVal and AnyRef in Scala 2.12.2+
       case seq: Seq[_] => seq.map {
         case b: java.lang.Byte => b.byteValue
@@ -303,6 +303,9 @@ object QueryTest {
       // Convert array to Seq for easy equality check.
       case b: Array[_] => b.toSeq
       case r: Row => prepareRow(r)
+      // spark treats -0.0 as 0.0
+      case d: Double if d == -0.0d => 0.0d
+      case f: Float if f == -0.0f => 0.0f
       case o => o
     })
   }