[SPARK-45392][SQL][FOLLOWUP] Restore the original exception from data…

… source

### What changes were proposed in this pull request?

This is a followup of #43193 to fix a behavior change. `Class.getDeclaredConstructor().newInstance()` will wrap the exception with `InvocationTargetException`, and this PR unwraps it to still throw the original exception from the data source

### Why are the changes needed?

restore a behavior change

### Does this PR introduce _any_ user-facing change?

no

### How was this patch tested?

new test

### Was this patch authored or co-authored using generative AI tooling?

no

Closes #43446 from cloud-fan/follow.

Authored-by: Wenchen Fan <wenchen@databricks.com>
Signed-off-by: yangjie01 <yangjie01@baidu.com>

sql/core/src/main/scala/org/apache/spark/sql/execution/datasources/DataSource.scala

@@ -699,7 +699,13 @@ object DataSource extends Logging {
     val useV1Sources = conf.getConf(SQLConf.USE_V1_SOURCE_LIST).toLowerCase(Locale.ROOT)
       .split(",").map(_.trim)
     val cls = lookupDataSource(provider, conf)
-    cls.getDeclaredConstructor().newInstance() match {
+    val instance = try {
+      cls.getDeclaredConstructor().newInstance()
+    } catch {
+      // Throw the original error from the data source implementation.
+      case e: java.lang.reflect.InvocationTargetException => throw e.getCause
+    }
+    instance match {
       case d: DataSourceRegister if useV1Sources.contains(d.shortName()) => None
       case t: TableProvider
           if !useV1Sources.contains(cls.getCanonicalName.toLowerCase(Locale.ROOT)) =>

sql/core/src/test/scala/org/apache/spark/sql/connector/DataSourceV2Suite.scala

@@ -77,6 +77,12 @@ class DataSourceV2Suite extends QueryTest with SharedSparkSession with AdaptiveS
     }.head
   }
 
+  test("invalid data source") {
+    intercept[IllegalArgumentException] {
+      spark.read.format(classOf[InvalidDataSource].getName).load()
+    }
+  }
+
   test("simplest implementation") {
     Seq(classOf[SimpleDataSourceV2], classOf[JavaSimpleDataSourceV2]).foreach { cls =>
       withClue(cls.getName) {
@@ -1155,3 +1161,9 @@ class ReportStatisticsDataSource extends SimpleWritableDataSource {
     }
   }
 }
+
+class InvalidDataSource extends TestingV2Source {
+  throw new IllegalArgumentException("test error")
+
+  override def getTable(options: CaseInsensitiveStringMap): Table = null
+}