fix SPARK-33566

Author: LuciferYang

sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/csv/CSVOptions.scala

@@ -213,6 +213,12 @@ class CSVOptions(
   }
   val lineSeparatorInWrite: Option[String] = lineSeparator
 
+  /**
+   * The handling method to be used when unescaped quotes are found in the input.
+   */
+  val unescapedQuoteHandling: UnescapedQuoteHandling = UnescapedQuoteHandling.valueOf(parameters
+    .getOrElse("unescapedQuoteHandling", "STOP_AT_DELIMITER").toUpperCase(Locale.ROOT))
+
   def asWriterSettings: CsvWriterSettings = {
     val writerSettings = new CsvWriterSettings()
     val format = writerSettings.getFormat
@@ -258,7 +264,7 @@ class CSVOptions(
     settings.setNullValue(nullValue)
     settings.setEmptyValue(emptyValueInRead)
     settings.setMaxCharsPerColumn(maxCharsPerColumn)
-    settings.setUnescapedQuoteHandling(UnescapedQuoteHandling.STOP_AT_DELIMITER)
+    settings.setUnescapedQuoteHandling(unescapedQuoteHandling)
     settings.setLineSeparatorDetectionEnabled(lineSeparatorInRead.isEmpty && multiLine)
     lineSeparatorInRead.foreach { _ =>
       settings.setNormalizeLineEndingsWithinQuotes(!multiLine)

sql/core/src/main/scala/org/apache/spark/sql/DataFrameReader.scala

@@ -727,6 +727,27 @@ class DataFrameReader private[sql](sparkSession: SparkSession) extends Logging {
    * a record can have.</li>
    * <li>`maxCharsPerColumn` (default `-1`): defines the maximum number of characters allowed
    * for any given value being read. By default, it is -1 meaning unlimited length</li>
+   * <li>`unescapedQuoteHandling` (default `STOP_AT_DELIMITER`): defines how the CsvParser
+   * will handle values with unescaped quotes.
+   *   <ul>
+   *     <li>`STOP_AT_CLOSING_QUOTE`: If unescaped quotes are found in the input, accumulate
+   *     the quote character and proceed parsing the value as a quoted value, until a closing
+   *     quote is found.</li>
+   *     <li>`BACK_TO_DELIMITER`: If unescaped quotes are found in the input, consider the value
+   *     as an unquoted value. This will make the parser accumulate all characters of the current
+   *     parsed value until the delimiter is found. If no
+   *     delimiter is found in the value, the parser will continue accumulating characters from
+   *     the input until a delimiter or line ending is found.</li>
+   *     <li>`STOP_AT_DELIMITER`: If unescaped quotes are found in the input, consider the value
+   *     as an unquoted value. This will make the parser accumulate all characters until the
+   *     delimiter or a line ending is found in the input.</li>
+   *     <li>`STOP_AT_DELIMITER`: If unescaped quotes are found in the input, the content parsed
+   *     for the given value will be skipped and the value set in nullValue will be produced
+   *     instead.</li>
+   *     <li>`RAISE_ERROR`: If unescaped quotes are found in the input, a TextParsingException
+   *     will be thrown.</li>
+   *   </ul>
+   * </li>
    * <li>`mode` (default `PERMISSIVE`): allows a mode for dealing with corrupt records
    *    during parsing. It supports the following case-insensitive modes. Note that Spark tries
    *    to parse only required columns in CSV under column pruning. Therefore, corrupt records

sql/core/src/test/resources/test-data/unescaped-quotes-unescaped-delimiter.csv

@@ -0,0 +1,3 @@
+c1,c2
+"a,""b,c","xyz"
+"a,b,c","x""yz"

sql/core/src/test/scala/org/apache/spark/sql/execution/datasources/csv/CSVSuite.scala

@@ -75,6 +75,8 @@ abstract class CSVSuite
   private val valueMalformedFile = "test-data/value-malformed.csv"
   private val badAfterGoodFile = "test-data/bad_after_good.csv"
   private val malformedRowFile = "test-data/malformedRow.csv"
+  private val unescapedQuotesAndUnescapedDelimiterFile =
+    "test-data/unescaped-quotes-unescaped-delimiter.csv"
 
   /** Verifies data and schema. */
   private def verifyCars(
@@ -2428,6 +2430,19 @@ abstract class CSVSuite
       assert(readback.collect sameElements Array(Row("0"), Row("1"), Row("2")))
     }
   }
+
+  test("SPARK-33566: configure UnescapedQuoteHandling to parse " +
+    "unescapedQuotesAndUnescapedDelimiterFile correctly") {
+    // Without configure UnescapedQuoteHandling to STOP_AT_CLOSING_QUOTE,
+    // the result will be Row(""""a,""b""", """c""""), Row("""a,b,c""", """"x""yz"""")
+    val result = spark.read
+      .option("inferSchema", "true")
+      .option("header", "true")
+      .option("unescapedQuoteHandling", "STOP_AT_CLOSING_QUOTE")
+      .csv(testFile(unescapedQuotesAndUnescapedDelimiterFile)).collect()
+    val exceptResults = Array(Row("""a,""b,c""", "xyz"), Row("""a,b,c""", """x""yz"""))
+    assert(result.sameElements(exceptResults))
+  }
 }
 
 class CSVv1Suite extends CSVSuite {