[WIP] Scala 2.12 / Spark 3 upgrade

core/src/main/scala/com/salesforce/op/filters/FeatureDistribution.scala

@@ -180,8 +180,8 @@ case class FeatureDistribution
     case _ => false
   }
 
-  override def hashCode(): Int = Objects.hashCode(name, key, count, nulls, distribution,
-    summaryInfo, moments, cardEstimate, `type`)
+  override def hashCode(): Int = Objects.hashCode((name, key, count, nulls, distribution.deep,
+    summaryInfo.deep, moments, cardEstimate, `type`))
 }
 
 object FeatureDistribution {

core/src/test/scala/com/salesforce/op/filters/FeatureDistributionTest.scala

@@ -192,7 +192,7 @@ class FeatureDistributionTest extends FlatSpec with PassengerSparkFixtureTest wi
     val fd2 = FeatureDistribution("A", None, 20, 20, Array(2, 8, 0, 0, 12), Array.empty)
     fd1.hashCode() shouldBe fd1.hashCode()
     fd1.hashCode() shouldBe fd1.copy(summaryInfo = fd1.summaryInfo).hashCode()
-    fd1.hashCode() should not be fd1.copy(summaryInfo = Array.empty).hashCode()
+    fd1.hashCode() shouldBe fd1.copy(summaryInfo = Array.empty).hashCode()
     fd1.hashCode() should not be fd2.hashCode()
   }