[SPARK-48806] Pass actual exception when url_decode fails

Author: wForget

sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/expressions/urlExpressions.scala

@@ -116,7 +116,7 @@ object UrlCodec {
       UTF8String.fromString(URLDecoder.decode(src.toString, enc.toString))
     } catch {
       case e: IllegalArgumentException =>
-        throw QueryExecutionErrors.illegalUrlError(src)
+        throw QueryExecutionErrors.illegalUrlError(src, e)
     }
   }
 }

sql/catalyst/src/main/scala/org/apache/spark/sql/errors/QueryExecutionErrors.scala

@@ -365,10 +365,11 @@ private[sql] object QueryExecutionErrors extends QueryErrorsBase with ExecutionE
       cause = e)
   }
 
-  def illegalUrlError(url: UTF8String): Throwable = {
+  def illegalUrlError(url: UTF8String, e: IllegalArgumentException): Throwable = {
     new SparkIllegalArgumentException(
       errorClass = "CANNOT_DECODE_URL",
-      messageParameters = Map("url" -> url.toString)
+      messageParameters = Map("url" -> url.toString),
+      cause = e
     )
   }
 

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

@@ -17,7 +17,7 @@
 
 package org.apache.spark.sql
 
-import org.apache.spark.{SPARK_DOC_ROOT, SparkRuntimeException}
+import org.apache.spark.{SPARK_DOC_ROOT, SparkIllegalArgumentException, SparkRuntimeException}
 import org.apache.spark.sql.catalyst.expressions.Cast._
 import org.apache.spark.sql.execution.FormattedMode
 import org.apache.spark.sql.functions._
@@ -1273,4 +1273,14 @@ class StringFunctionsSuite extends QueryTest with SharedSparkSession {
       )
     )
   }
+
+  test("url_decode exception") {
+    val e = intercept[SparkIllegalArgumentException] {
+      sql("select url_decode('https%3A%2F%2spark.apache.org')").collect()
+    }
+    e.printStackTrace()
+    assert(e.getCause.isInstanceOf[IllegalArgumentException] &&
+      e.getCause.getMessage
+        .startsWith("URLDecoder: Illegal hex characters in escape (%) pattern - "))
+  }
 }