Remove quotes

Author: srowen

sql/catalyst/src/main/scala/org/apache/spark/sql/types/StructType.scala

@@ -56,7 +56,7 @@ import org.apache.spark.sql.catalyst.util.{quoteIdentifier, truncatedString}
  *
  * // If this struct does not have a field called "d", it throws an exception.
  * struct("d")
- * // java.lang.IllegalArgumentException: "d" does not exist.
+ * // java.lang.IllegalArgumentException: d does not exist.
  * //   ...
  *
  * // Extract multiple StructFields. Field names are provided in a set.
@@ -68,7 +68,7 @@ import org.apache.spark.sql.catalyst.util.{quoteIdentifier, truncatedString}
  * // Any names without matching fields will throw an exception.
  * // For the case shown below, an exception is thrown due to "d".
  * struct(Set("b", "c", "d"))
- * // java.lang.IllegalArgumentException: "d" does not exist.
+ * // java.lang.IllegalArgumentException: d does not exist.
  * //    ...
  * }}}
  *
@@ -271,22 +271,21 @@ case class StructType(fields: Array[StructField]) extends DataType with Seq[Stru
   def apply(name: String): StructField = {
     nameToField.getOrElse(name,
       throw new IllegalArgumentException(
-        s""""$name" does not exist.
-           |Available: ${fieldNames.mkString("\"", "\", \"", "\"")}""".stripMargin))
+        s"$name does not exist. Available: ${fieldNames.mkString(", ")}"))
   }
 
   /**
    * Returns a [[StructType]] containing [[StructField]]s of the given names, preserving the
    * original order of fields.
    *
-   * @throws IllegalArgumentException if a field cannot be found for any of the given names
+   * @throws IllegalArgumentException if at least one given field name does not exist
    */
   def apply(names: Set[String]): StructType = {
     val nonExistFields = names -- fieldNamesSet
     if (nonExistFields.nonEmpty) {
       throw new IllegalArgumentException(
-        s"""${nonExistFields.mkString(", ")} do(es) not exist.
-           |Available: ${fieldNames.mkString("\"", "\", \"", "\"")}""".stripMargin)
+        s"${nonExistFields.mkString(", ")} do(es) not exist. " +
+          s"Available: ${fieldNames.mkString(", ")}")
     }
     // Preserve the original order of fields.
     StructType(fields.filter(f => names.contains(f.name)))
@@ -300,8 +299,7 @@ case class StructType(fields: Array[StructField]) extends DataType with Seq[Stru
   def fieldIndex(name: String): Int = {
     nameToIndex.getOrElse(name,
       throw new IllegalArgumentException(
-        s""""$name" does not exist.
-           |Available: ${fieldNames.mkString("\"", "\", \"", "\"")}""".stripMargin))
+        s"$name does not exist. Available: ${fieldNames.mkString(", ")}"))
   }
 
   private[sql] def getFieldIndex(name: String): Option[Int] = {

sql/catalyst/src/test/scala/org/apache/spark/sql/types/StructTypeSuite.scala

@@ -26,17 +26,17 @@ class StructTypeSuite extends SparkFunSuite {
 
   test("lookup a single missing field should output existing fields") {
     val e = intercept[IllegalArgumentException](s("c")).getMessage
-    assert(e.contains("Available: \"a\", \"b\""))
+    assert(e.contains("Available: a, b"))
   }
 
   test("lookup a set of missing fields should output existing fields") {
     val e = intercept[IllegalArgumentException](s(Set("a", "c"))).getMessage
-    assert(e.contains("Available: \"a\", \"b\""))
+    assert(e.contains("Available: a, b"))
   }
 
   test("lookup fieldIndex for missing field should output existing fields") {
     val e = intercept[IllegalArgumentException](s.fieldIndex("c")).getMessage
-    assert(e.contains("Available: \"a\", \"b\""))
+    assert(e.contains("Available: a, b"))
   }
 
   test("SPARK-24849: toDDL - simple struct") {