[SPARK-31892][SQL] Disable week-based date filed for parsing

docs/sql-ref-datetime-pattern.md

@@ -136,6 +136,8 @@ The count of pattern letters determines the format.
   During formatting, all valid data will be output even it is in the optional section.
   During parsing, the whole section may be missing from the parsed string.
   An optional section is started by `[` and ended using `]` (or at the end of the pattern).
+
+- Symbols of 'Y', 'W', 'w', 'E', 'u', 'F', 'q' and 'Q' can only be used for datetime formatting, e.g. `date_format`. They are not allowed used for datetime parsing, e.g. `to_timestamp`.
 
 More details for the text style:
 

sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/catalog/interface.scala

@@ -525,7 +525,7 @@ object CatalogColumnStat extends Logging {
     TimestampFormatter(
       format = "yyyy-MM-dd HH:mm:ss.SSSSSS",
       zoneId = ZoneOffset.UTC,
-      needVarLengthSecondFraction = isParsing)
+      isParsing = isParsing)
   }
 
   /**

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

@@ -35,7 +35,7 @@ class CSVInferSchema(val options: CSVOptions) extends Serializable {
     options.zoneId,
     options.locale,
     legacyFormat = FAST_DATE_FORMAT,
-    needVarLengthSecondFraction = true)
+    isParsing = true)
 
   private val decimalParser = if (options.locale == Locale.US) {
     // Special handling the default locale for backward compatibility

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

@@ -47,12 +47,13 @@ class UnivocityGenerator(
     options.zoneId,
     options.locale,
     legacyFormat = FAST_DATE_FORMAT,
-    needVarLengthSecondFraction = false)
+    isParsing = false)
   private val dateFormatter = DateFormatter(
     options.dateFormat,
     options.zoneId,
     options.locale,
-    legacyFormat = FAST_DATE_FORMAT)
+    legacyFormat = FAST_DATE_FORMAT,
+    isParsing = false)
 
   private def makeConverter(dataType: DataType): ValueConverter = dataType match {
     case DateType =>

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

@@ -90,12 +90,13 @@ class UnivocityParser(
     options.zoneId,
     options.locale,
     legacyFormat = FAST_DATE_FORMAT,
-    needVarLengthSecondFraction = true)
+    isParsing = true)
   private lazy val dateFormatter = DateFormatter(
     options.dateFormat,
     options.zoneId,
     options.locale,
-    legacyFormat = FAST_DATE_FORMAT)
+    legacyFormat = FAST_DATE_FORMAT,
+    isParsing = true)
 
   private val csvFilters = new CSVFilters(filters, requiredSchema)
 

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

@@ -734,7 +734,7 @@ case class DateFormatClass(left: Expression, right: Expression, timeZoneId: Opti
           format.toString,
           zoneId,
           legacyFormat = SIMPLE_DATE_FORMAT,
-          needVarLengthSecondFraction = false)
+          isParsing = false)
       }
     } else None
   }
@@ -745,7 +745,7 @@ case class DateFormatClass(left: Expression, right: Expression, timeZoneId: Opti
         format.toString,
         zoneId,
         legacyFormat = SIMPLE_DATE_FORMAT,
-        needVarLengthSecondFraction = false)
+        isParsing = false)
     } else {
       formatter.get
     }
@@ -890,7 +890,7 @@ abstract class ToTimestamp
         constFormat.toString,
         zoneId,
         legacyFormat = SIMPLE_DATE_FORMAT,
-        needVarLengthSecondFraction = true)
+        isParsing = true)
     } catch {
       case e: SparkUpgradeException => throw e
       case NonFatal(_) => null
@@ -929,7 +929,7 @@ abstract class ToTimestamp
                 formatString,
                 zoneId,
                 legacyFormat = SIMPLE_DATE_FORMAT,
-                needVarLengthSecondFraction = true)
+                isParsing = true)
                 .parse(t.asInstanceOf[UTF8String].toString) / downScaleFactor
             } catch {
               case e: SparkUpgradeException => throw e
@@ -1072,7 +1072,7 @@ case class FromUnixTime(sec: Expression, format: Expression, timeZoneId: Option[
         constFormat.toString,
         zoneId,
         legacyFormat = SIMPLE_DATE_FORMAT,
-        needVarLengthSecondFraction = false)
+        isParsing = false)
     } catch {
       case e: SparkUpgradeException => throw e
       case NonFatal(_) => null
@@ -1105,7 +1105,7 @@ case class FromUnixTime(sec: Expression, format: Expression, timeZoneId: Option[
                 f.toString,
                 zoneId,
                 legacyFormat = SIMPLE_DATE_FORMAT,
-                needVarLengthSecondFraction = false)
+                isParsing = false)
                 .format(time.asInstanceOf[Long] * MICROS_PER_SECOND))
           } catch {
             case e: SparkUpgradeException => throw e

sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/json/JacksonGenerator.scala

@@ -83,12 +83,13 @@ private[sql] class JacksonGenerator(
     options.zoneId,
     options.locale,
     legacyFormat = FAST_DATE_FORMAT,
-    needVarLengthSecondFraction = false)
+    isParsing = false)
   private val dateFormatter = DateFormatter(
     options.dateFormat,
     options.zoneId,
     options.locale,
-    legacyFormat = FAST_DATE_FORMAT)
+    legacyFormat = FAST_DATE_FORMAT,
+    isParsing = false)
 
   private def makeWriter(dataType: DataType): ValueWriter = dataType match {
     case NullType =>

sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/json/JacksonParser.scala

@@ -61,12 +61,13 @@ class JacksonParser(
     options.zoneId,
     options.locale,
     legacyFormat = FAST_DATE_FORMAT,
-    needVarLengthSecondFraction = true)
+    isParsing = true)
   private lazy val dateFormatter = DateFormatter(
     options.dateFormat,
     options.zoneId,
     options.locale,
-    legacyFormat = FAST_DATE_FORMAT)
+    legacyFormat = FAST_DATE_FORMAT,
+    isParsing = true)
 
   /**
    * Create a converter which converts the JSON documents held by the `JsonParser`

sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/json/JsonInferSchema.scala

@@ -43,7 +43,7 @@ private[sql] class JsonInferSchema(options: JSONOptions) extends Serializable {
     options.zoneId,
     options.locale,
     legacyFormat = FAST_DATE_FORMAT,
-    needVarLengthSecondFraction = true)
+    isParsing = true)
 
   /**
    * Infer the type of a collection of json records in three stages:

sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/util/DateFormatter.scala

@@ -19,7 +19,6 @@ package org.apache.spark.sql.catalyst.util
 
 import java.text.SimpleDateFormat
 import java.time.{LocalDate, ZoneId}
-import java.time.format.DateTimeFormatter
 import java.util.{Date, Locale}
 
 import org.apache.commons.lang3.time.FastDateFormat
@@ -42,7 +41,8 @@ class Iso8601DateFormatter(
     pattern: String,
     zoneId: ZoneId,
     locale: Locale,
-    legacyFormat: LegacyDateFormats.LegacyDateFormat)
+    legacyFormat: LegacyDateFormats.LegacyDateFormat,
+    isParsing: Boolean)
   extends DateFormatter with DateTimeFormatterHelper {
 
   @transient
@@ -125,12 +125,13 @@ object DateFormatter {
       format: Option[String],
       zoneId: ZoneId,
       locale: Locale = defaultLocale,
-      legacyFormat: LegacyDateFormat = LENIENT_SIMPLE_DATE_FORMAT): DateFormatter = {
+      legacyFormat: LegacyDateFormat = LENIENT_SIMPLE_DATE_FORMAT,
+      isParsing: Boolean = true): DateFormatter = {
     val pattern = format.getOrElse(defaultPattern)
     if (SQLConf.get.legacyTimeParserPolicy == LEGACY) {
       getLegacyFormatter(pattern, zoneId, locale, legacyFormat)
     } else {
-      val df = new Iso8601DateFormatter(pattern, zoneId, locale, legacyFormat)
+      val df = new Iso8601DateFormatter(pattern, zoneId, locale, legacyFormat, isParsing)
       df.validatePatternString()
       df
     }
@@ -153,8 +154,9 @@ object DateFormatter {
       format: String,
       zoneId: ZoneId,
       locale: Locale,
-      legacyFormat: LegacyDateFormat): DateFormatter = {
-    getFormatter(Some(format), zoneId, locale, legacyFormat)
+      legacyFormat: LegacyDateFormat,
+      isParsing: Boolean): DateFormatter = {
+    getFormatter(Some(format), zoneId, locale, legacyFormat, isParsing)
   }
 
   def apply(format: String, zoneId: ZoneId): DateFormatter = {

sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/util/DateTimeFormatterHelper.scala

@@ -89,9 +89,9 @@ trait DateTimeFormatterHelper {
   protected def getOrCreateFormatter(
       pattern: String,
       locale: Locale,
-      needVarLengthSecondFraction: Boolean = false): DateTimeFormatter = {
-    val newPattern = convertIncompatiblePattern(pattern)
-    val useVarLen = needVarLengthSecondFraction && newPattern.contains('S')
+      isParsing: Boolean = false): DateTimeFormatter = {
+    val newPattern = convertIncompatiblePattern(pattern, isParsing)
+    val useVarLen = isParsing && newPattern.contains('S')
     val key = (newPattern, locale, useVarLen)
     var formatter = cache.getIfPresent(key)
     if (formatter == null) {
@@ -227,6 +227,12 @@ private object DateTimeFormatterHelper {
     formatter.format(LocalDate.of(2000, 1, 1)) == "1 1"
   }
   final val unsupportedLetters = Set('A', 'c', 'e', 'n', 'N', 'p')
+  // SPARK-31892: The week-based date fields are rarely used and really confusing for parsing values
+  // to datetime, especially when they are mixed with other non-week-based ones
+  // The quarter fields will also be parsed strangely, e.g. when the pattern contains `yMd` and can
+  // be directly resolved then the `q` do check for whether the month is valid, but if the date
+  // fields is incomplete, e.g. `yM`, the checking will be bypassed.
+  final val unsupportedLettersForParsing = Set('Y', 'W', 'w', 'E', 'u', 'F', 'q', 'Q')
   final val unsupportedPatternLengths = {
     // SPARK-31771: Disable Narrow-form TextStyle to avoid silent data change, as it is Full-form in
     // 2.4
@@ -246,7 +252,7 @@ private object DateTimeFormatterHelper {
    * @param pattern The input pattern.
    * @return The pattern for new parser
    */
-  def convertIncompatiblePattern(pattern: String): String = {
+  def convertIncompatiblePattern(pattern: String, isParsing: Boolean = false): String = {
     val eraDesignatorContained = pattern.split("'").zipWithIndex.exists {
       case (patternPart, index) =>
         // Text can be quoted using single quotes, we only check the non-quote parts.
@@ -255,7 +261,8 @@ private object DateTimeFormatterHelper {
     (pattern + " ").split("'").zipWithIndex.map {
       case (patternPart, index) =>
         if (index % 2 == 0) {
-          for (c <- patternPart if unsupportedLetters.contains(c)) {
+          for (c <- patternPart if unsupportedLetters.contains(c) ||
+            (isParsing && unsupportedLettersForParsing.contains(c))) {
             throw new IllegalArgumentException(s"Illegal pattern character: $c")
           }
           for (style <- unsupportedPatternLengths if patternPart.contains(style)) {

sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/util/TimestampFormatter.scala

@@ -287,13 +287,13 @@ object TimestampFormatter {
       zoneId: ZoneId,
       locale: Locale = defaultLocale,
       legacyFormat: LegacyDateFormat = LENIENT_SIMPLE_DATE_FORMAT,
-      needVarLengthSecondFraction: Boolean = false): TimestampFormatter = {
+      isParsing: Boolean = false): TimestampFormatter = {
     val pattern = format.getOrElse(defaultPattern)
     if (SQLConf.get.legacyTimeParserPolicy == LEGACY) {
       getLegacyFormatter(pattern, zoneId, locale, legacyFormat)
     } else {
       val tf = new Iso8601TimestampFormatter(
-        pattern, zoneId, locale, legacyFormat, needVarLengthSecondFraction)
+        pattern, zoneId, locale, legacyFormat, isParsing)
       tf.validatePatternString()
       tf
     }
@@ -319,23 +319,23 @@ object TimestampFormatter {
       zoneId: ZoneId,
       locale: Locale,
       legacyFormat: LegacyDateFormat,
-      needVarLengthSecondFraction: Boolean): TimestampFormatter = {
-    getFormatter(Some(format), zoneId, locale, legacyFormat, needVarLengthSecondFraction)
+      isParsing: Boolean): TimestampFormatter = {
+    getFormatter(Some(format), zoneId, locale, legacyFormat, isParsing)
   }
 
   def apply(
       format: String,
       zoneId: ZoneId,
       legacyFormat: LegacyDateFormat,
-      needVarLengthSecondFraction: Boolean): TimestampFormatter = {
-    getFormatter(Some(format), zoneId, defaultLocale, legacyFormat, needVarLengthSecondFraction)
+      isParsing: Boolean): TimestampFormatter = {
+    getFormatter(Some(format), zoneId, defaultLocale, legacyFormat, isParsing)
   }
 
   def apply(
       format: String,
       zoneId: ZoneId,
-      needVarLengthSecondFraction: Boolean = false): TimestampFormatter = {
-    getFormatter(Some(format), zoneId, needVarLengthSecondFraction = needVarLengthSecondFraction)
+      isParsing: Boolean = false): TimestampFormatter = {
+    getFormatter(Some(format), zoneId, isParsing = isParsing)
   }
 
   def apply(zoneId: ZoneId): TimestampFormatter = {

sql/catalyst/src/test/scala/org/apache/spark/sql/catalyst/expressions/DateExpressionsSuite.scala

@@ -1168,4 +1168,33 @@ class DateExpressionsSuite extends SparkFunSuite with ExpressionEvalHelper {
     checkExceptionInExpression[ArithmeticException](
       MillisToTimestamp(Literal(-92233720368547758L)), "long overflow")
   }
+
+  test("Disable week-based date fields and quarter fields for parsing") {
+
+    def checkSparkUpgrade(c: Char): Unit = {
+      checkExceptionInExpression[SparkUpgradeException](
+        new ParseToTimestamp(Literal("1"), Literal(c.toString)).child, "3.0")
+      checkExceptionInExpression[SparkUpgradeException](
+        new ParseToDate(Literal("1"), Literal(c.toString)).child, "3.0")
+      checkExceptionInExpression[SparkUpgradeException](
+        ToUnixTimestamp(Literal("1"), Literal(c.toString)), "3.0")
+      checkExceptionInExpression[SparkUpgradeException](
+        UnixTimestamp(Literal("1"), Literal(c.toString)), "3.0")
+    }
+
+    def checkNullify(c: Char): Unit = {
+      checkEvaluation(new ParseToTimestamp(Literal("1"), Literal(c.toString)).child, null)
+      checkEvaluation(new ParseToDate(Literal("1"), Literal(c.toString)).child, null)
+      checkEvaluation(ToUnixTimestamp(Literal("1"), Literal(c.toString)), null)
+      checkEvaluation(UnixTimestamp(Literal("1"), Literal(c.toString)), null)
+    }
+
+    Seq('Y', 'W', 'w', 'E', 'u', 'F').foreach { l =>
+      checkSparkUpgrade(l)
+    }
+
+    Seq('q', 'Q').foreach { l =>
+      checkNullify(l)
+    }
+  }
 }

sql/catalyst/src/test/scala/org/apache/spark/sql/catalyst/util/DateTimeFormatterHelperSuite.scala

@@ -17,7 +17,7 @@
 
 package org.apache.spark.sql.catalyst.util
 
-import org.apache.spark.{SparkFunSuite, SparkUpgradeException}
+import org.apache.spark.SparkFunSuite
 import org.apache.spark.sql.catalyst.util.DateTimeFormatterHelper._
 
 class DateTimeFormatterHelperSuite extends SparkFunSuite {
@@ -40,6 +40,13 @@ class DateTimeFormatterHelperSuite extends SparkFunSuite {
       val e = intercept[IllegalArgumentException](convertIncompatiblePattern(s"yyyy-MM-dd $l G"))
       assert(e.getMessage === s"Illegal pattern character: $l")
     }
+    unsupportedLettersForParsing.foreach { l =>
+      val e = intercept[IllegalArgumentException] {
+        convertIncompatiblePattern(s"$l", isParsing = true)
+      }
+      assert(e.getMessage === s"Illegal pattern character: $l")
+      assert(convertIncompatiblePattern(s"$l").nonEmpty)
+    }
     unsupportedPatternLengths.foreach { style =>
       val e1 = intercept[IllegalArgumentException] {
         convertIncompatiblePattern(s"yyyy-MM-dd $style")

sql/catalyst/src/test/scala/org/apache/spark/sql/util/DateFormatterSuite.scala

@@ -72,7 +72,8 @@ class DateFormatterSuite extends SparkFunSuite with SQLHelper {
                   DateFormatter.defaultPattern,
                   getZoneId(timeZone),
                   DateFormatter.defaultLocale,
-                  legacyFormat)
+                  legacyFormat,
+                  isParsing = false)
                 val days = formatter.parse(date)
                 assert(date === formatter.format(days))
                 assert(date === formatter.format(daysToLocalDate(days)))
@@ -106,7 +107,8 @@ class DateFormatterSuite extends SparkFunSuite with SQLHelper {
                   DateFormatter.defaultPattern,
                   getZoneId(timeZone),
                   DateFormatter.defaultLocale,
-                  legacyFormat)
+                  legacyFormat,
+                  isParsing = false)
                 val date = formatter.format(days)
                 val parsed = formatter.parse(date)
                 assert(days === parsed)
@@ -173,7 +175,8 @@ class DateFormatterSuite extends SparkFunSuite with SQLHelper {
               DateFormatter.defaultPattern,
               getZoneId(timeZone),
               DateFormatter.defaultLocale,
-              legacyFormat)
+              legacyFormat,
+              isParsing = false)
             assert(LocalDate.ofEpochDay(formatter.parse("1000-01-01")) === LocalDate.of(1000, 1, 1))
             assert(formatter.format(LocalDate.of(1000, 1, 1)) === "1000-01-01")
             assert(formatter.format(localDateToDays(LocalDate.of(1000, 1, 1))) === "1000-01-01")