Spark单元测试：对象不可序列化（类：org.scalatest.Assertions $ AssertionsHelper）

Question

我已经编写了通用的Scala方法，该方法在读取配置单元列定义之后创建了配置单元表。方法的签名，同样是：

def createHiveTable(tableName: String, metaDataList: List[SchemaColumnDefinition]) = { ....}

case class SchemaColumnDefinition(name: String,
                                  dataType: String,
                                  precision: Option[Integer],
                                  scale: Option[Integer]) {

我已经为同一单元编写了一个单元测试用例

  "createHiveTable" should " create hive table with provided column definition" in {
    // GIVEN
    val columns = SchemaColumnDefinition("testIntColumn", "INT", None, None) ::
      SchemaColumnDefinition("testStringColumn", "STRING", None, None) ::
      SchemaColumnDefinition("testDecimalColumn", "DECIMAL", None, None) ::
      Nil
    val testTableName = "testTable"
    // WHEN
    HiveTableManager.createHiveTable(testTableName, columns)
    // THEN
    sparkSession.catalog.listColumns(testTableName).foreach { columnDefinition =>
      columnDefinition.name match {
        case "testIntColumn" => assert(columnDefinition.dataType.toLowerCase == "int")
        case "testStringColumn" => assert(columnDefinition.dataType.toLowerCase == "string")
        case "testDecimalColumn" => assert(columnDefinition.dataType.toLowerCase == "decimal(10,0)")
      }
    }
  }

但是在同样运行时，出现以下异常：

[scalatest]   Cause: java.io.NotSerializableException: org.scalatest.Assertions$AssertionsHelper
[scalatest] Serialization stack:
[scalatest]         - object not serializable (class: org.scalatest.Assertions$AssertionsHelper, value: org.scalatest.Assertions$AssertionsHelper@420068a)
[scalatest]         - field (class: org.scalatest.FlatSpec, name: assertionsHelper, type: class org.scalatest.Assertions$AssertionsHelper)
[scalatest]         - object (class com.demo.spark.executor.hive.HiveTableManagerTest, HiveTableManagerTest)

complete log

如果我将“ assert”替换为“ println”语句，则测试用例通过。

我尝试用“ Serializable”扩展测试类，但仍然存在相同的异常。