Add helper function to return the number of days since epoch for a week-of-month date

velox/type/TimestampConversion.cpp

@@ -42,6 +42,7 @@
 
 #include "velox/type/TimestampConversion.h"
 #include <folly/Expected.h>
+#include "HugeInt.h"
 #include "velox/common/base/CheckedArithmetic.h"
 #include "velox/common/base/Exceptions.h"
 #include "velox/type/tz/TimeZoneMap.h"
@@ -144,6 +145,53 @@ bool isValidWeekDate(int32_t weekYear, int32_t weekOfYear, int32_t dayOfWeek) {
   return true;
 }
 
+bool isValidWeekOfMonthDate(
+    int32_t year,
+    int32_t month,
+    int32_t weekOfMonth,
+    int32_t dayOfWeek) {
+  if (year < 1 || year > kMaxYear) {
+    return false;
+  }
+  if (month < 1 || month > 12) {
+    return false;
+  }
+
+  int64_t daysSinceEpochOfFirstDayOfMonth;
+  const Status status =
+      daysSinceEpochFromDate(year, month, 1, daysSinceEpochOfFirstDayOfMonth);
+  if (!status.ok()) {
+    return false;
+  }
+
+  // Calculates the max week of month and validates if it is in the valid range.
+  const int32_t firstDayOfWeek =
+      extractISODayOfTheWeek(daysSinceEpochOfFirstDayOfMonth);
+  const int32_t firstWeekLength = 7 - firstDayOfWeek + 1;
+  const int32_t monthLength =
+      isLeapYear(year) ? kLeapDays[month] : kNormalDays[month];
+  const int32_t maxWeekOfMonth =
+      1 + ceil((monthLength - firstWeekLength) / 7.0);
+  if (weekOfMonth < 1 || weekOfMonth > maxWeekOfMonth) {
+    return false;
+  }
+
+  // Validate day of week.
+  // If dayOfWeek is before the first day of week, it is considered invalid.
+  if (weekOfMonth == 1 && dayOfWeek < firstDayOfWeek) {
+    return false;
+  }
+  const int32_t lastWeekLength = (monthLength - firstWeekLength) % 7;
+  // If dayOfWeek is after the last day of the last week of the month, it is
+  // considered invalid.
+  if (weekOfMonth == maxWeekOfMonth && lastWeekLength != 0 &&
+      dayOfWeek > lastWeekLength) {
+    return false;
+  }
+
+  return true;
+}
+
 inline bool validDate(int64_t daysSinceEpoch) {
   return daysSinceEpoch >= std::numeric_limits<int32_t>::min() &&
       daysSinceEpoch <= std::numeric_limits<int32_t>::max();
@@ -593,6 +641,59 @@ Status daysSinceEpochFromWeekDate(
   return Status::OK();
 }
 
+Expected<int64_t> daysSinceEpochFromWeekOfMonthDate(
+    int32_t year,
+    int32_t month,
+    int32_t weekOfMonth,
+    int32_t dayOfWeek,
+    bool lenient) {
+  if (!lenient &&
+      !isValidWeekOfMonthDate(year, month, weekOfMonth, dayOfWeek)) {
+    if (threadSkipErrorDetails()) {
+      return folly::makeUnexpected(Status::UserError());
+    } else {
+      return folly::makeUnexpected(Status::UserError(
+          "Date out of range: {}-{}-{}-{}",
+          year,
+          month,
+          weekOfMonth,
+          dayOfWeek));
+    }
+  }
+
+  // Adjusts the year and month to ensure month is within the range 1-12,
+  // accounting for overflow or underflow.
+  int32_t additionYears = 0;
+  if (month < 1) {
+    additionYears = month / 12 - 1;
+    month = 12 - abs(month) % 12;
+  } else if (month > 12) {
+    additionYears = (month - 1) / 12;
+    month = (month - 1) % 12 + 1;
+  }
+  year += additionYears;
+
+  int64_t daysSinceEpochOfFirstDayOfMonth;
+  Status status =
+      daysSinceEpochFromDate(year, month, 1, daysSinceEpochOfFirstDayOfMonth);
+  if (!status.ok()) {
+    return folly::makeUnexpected(status);
+  }
+  int32_t firstDayOfWeek =
+      extractISODayOfTheWeek(daysSinceEpochOfFirstDayOfMonth);
+  int32_t days;
+  if (dayOfWeek < 1) {
+    days = 7 - abs(dayOfWeek - 1) % 7;
+  } else if (dayOfWeek > 7) {
+    days = (dayOfWeek - 1) % 7;
+  } else {
+    days = dayOfWeek % 7;
+  }
+  int64_t result = daysSinceEpochOfFirstDayOfMonth - (firstDayOfWeek - 1) +
+      7 * (weekOfMonth - 1) + days - 1;
+  return result;
+}
+
 Status
 daysSinceEpochFromDayOfYear(int32_t year, int32_t dayOfYear, int64_t& out) {
   if (!isValidDayOfYear(year, dayOfYear)) {
@@ -643,7 +744,7 @@ Expected<int32_t> fromDateString(const char* str, size_t len, ParseMode mode) {
   return daysSinceEpoch;
 }
 
-int32_t extractISODayOfTheWeek(int32_t daysSinceEpoch) {
+int32_t extractISODayOfTheWeek(int64_t daysSinceEpoch) {
   // date of 0 is 1970-01-01, which was a Thursday (4)
   // -7 = 4
   // -6 = 5
@@ -662,10 +763,10 @@ int32_t extractISODayOfTheWeek(int32_t daysSinceEpoch) {
   // 7  = 4
   if (daysSinceEpoch < 0) {
     // negative date: start off at 4 and cycle downwards
-    return (7 - ((-int64_t(daysSinceEpoch) + 3) % 7));
+    return (7 - ((-int128_t(daysSinceEpoch) + 3) % 7));
   } else {
     // positive date: start off at 4 and cycle upwards
-    return ((int64_t(daysSinceEpoch) + 3) % 7) + 1;
+    return ((int128_t(daysSinceEpoch) + 3) % 7) + 1;
   }
 }
 

velox/type/TimestampConversion.h

@@ -107,6 +107,37 @@ Status daysSinceEpochFromWeekDate(
     int32_t dayOfWeek,
     int64_t& out);
 
+/// Computes the signed number of days since the Unix epoch (1970-01-01). To
+/// align with Spark's SimpleDateFormat behavior, this function offers two
+/// modes: lenient and non-lenient. If `lenient` is false, it returns an error
+/// status if the date is invalid. If `lenient` is true, it accepts a wider
+/// range of arguments.
+/// @param year Year. For non-lenient mode, it should be in the range [1,
+/// 292278994]. e.g: 1996, -2000
+/// @param month Month of year. For non-lenient mode, it should be in the range
+/// [1, 12]. For example, 1 is Jan, 7 is Jul. For lenient mode, values greater
+/// than 12 wrap around to the start of the year, and values less than 1 count
+/// backward from December. For example, 13 corresponds to January of the
+/// following year and -1 corresponds to November of the previous year.
+/// @param weekOfMonth Week of the month. For non-lenient mode, it should be in
+/// the range [1, 6]. For example, 1 is 1st week, 3 is 3rd week. For lenient
+/// mode, we consider days of the previous or next months as part of the
+/// specified weekOfMonth. For example, if weekOfMonth is 5 but the current
+/// month only has 4 weeks (such as February), the first week of March will be
+/// considered as the 5th week of February.
+/// @param dayOfWeek Day number of week. For non-lenient mode, it should be in
+/// the range [1, 7]. For example, 1 is Monday, 7 is Sunday. For lenient mode,
+/// we consider days of the previous or next months as part of the specified
+/// dayOfWeek.For example, if weekOfMonth is 1 and dayOfWeek is 1 but the
+/// month's first day is Saturday, the Monday of the last week of the previous
+/// month will be used.
+Expected<int64_t> daysSinceEpochFromWeekOfMonthDate(
+    int32_t year,
+    int32_t month,
+    int32_t weekOfMonth,
+    int32_t dayOfWeek,
+    bool lenient);
+
 /// Computes the (signed) number of days since unix epoch (1970-01-01).
 /// Returns UserError status if the date is invalid.
 Status
@@ -123,7 +154,7 @@ inline Expected<int32_t> fromDateString(const StringView& str, ParseMode mode) {
 }
 
 // Extracts the day of the week from the number of days since epoch
-int32_t extractISODayOfTheWeek(int32_t daysSinceEpoch);
+int32_t extractISODayOfTheWeek(int64_t daysSinceEpoch);
 
 /// Time conversions.
 

velox/type/tests/TimestampConversionTest.cpp

@@ -104,6 +104,84 @@ TEST(DateTimeUtilTest, fromDateInvalid) {
       1970, 6, 31, "Date out of range: 1970-6-31"));
 }
 
+TEST(DateTimeUtilTest, fromWeekOfMonthDate) {
+  auto daysSinceEpoch =
+      [](int32_t year, int32_t month, int32_t weekOfMonth, int32_t dayOfWeek) {
+        auto result = util::daysSinceEpochFromWeekOfMonthDate(
+            year, month, weekOfMonth, dayOfWeek, true);
+        EXPECT_TRUE(!result.hasError());
+        return result.value();
+      };
+  EXPECT_EQ(4, daysSinceEpoch(1970, 1, 2, 1));
+  EXPECT_EQ(361, daysSinceEpoch(1971, 1, 1, 1));
+  EXPECT_EQ(396, daysSinceEpoch(1971, 2, 1, 1));
+
+  EXPECT_EQ(10952, daysSinceEpoch(2000, 1, 1, 1));
+  EXPECT_EQ(19905, daysSinceEpoch(2024, 7, 1, 1));
+
+  // Before unix epoch.
+  EXPECT_EQ(-3, daysSinceEpoch(1970, 1, 1, 1));
+  EXPECT_EQ(-2, daysSinceEpoch(1970, 1, 1, 2));
+  EXPECT_EQ(-31, daysSinceEpoch(1969, 12, 1, 1));
+  EXPECT_EQ(-367, daysSinceEpoch(1969, 1, 1, 1));
+  EXPECT_EQ(-724, daysSinceEpoch(1968, 1, 2, 1));
+  EXPECT_EQ(-719533, daysSinceEpoch(0, 1, 1, 1));
+
+  // Negative year - BC.
+  EXPECT_EQ(-719561, daysSinceEpoch(-1, 12, 1, 1));
+  EXPECT_EQ(-719897, daysSinceEpoch(-1, 1, 1, 1));
+
+  // Day in the previous month.
+  EXPECT_EQ(19783, daysSinceEpoch(2024, 2, 5, 5));
+  // Day in the next month.
+  EXPECT_EQ(19751, daysSinceEpoch(2024, 2, 1, 1));
+
+  // Out of range day of week.
+  EXPECT_EQ(338, daysSinceEpoch(1970, 12, 1, 0));
+  EXPECT_EQ(337, daysSinceEpoch(1970, 12, 1, -1));
+  EXPECT_EQ(337, daysSinceEpoch(1970, 12, 1, -8));
+
+  EXPECT_EQ(332, daysSinceEpoch(1970, 12, 1, 8));
+  EXPECT_EQ(333, daysSinceEpoch(1970, 12, 1, 9));
+  EXPECT_EQ(336, daysSinceEpoch(1970, 12, 1, 19));
+
+  // Out of range month.
+  EXPECT_EQ(-3, daysSinceEpoch(1970, 1, 1, 1));
+  EXPECT_EQ(207, daysSinceEpoch(1970, 8, 1, 1));
+  EXPECT_EQ(361, daysSinceEpoch(1970, 13, 1, 1));
+
+  EXPECT_EQ(-31, daysSinceEpoch(1970, 0, 1, 1));
+  EXPECT_EQ(-66, daysSinceEpoch(1970, -1, 1, 1));
+  EXPECT_EQ(-430, daysSinceEpoch(1970, -13, 1, 1));
+}
+
+TEST(DateTimeUtilTest, fromWeekOfMonthDateInvalid) {
+  auto daysSinceEpoch = [](int32_t year,
+                           int32_t month,
+                           int32_t weekOfMonth,
+                           int32_t dayOfWeek,
+                           const std::string& error) {
+    auto result = util::daysSinceEpochFromWeekOfMonthDate(
+        year, month, weekOfMonth, dayOfWeek, false);
+    EXPECT_TRUE(result.error().isUserError());
+    EXPECT_EQ(result.error().message(), error);
+  };
+
+  EXPECT_NO_THROW(daysSinceEpoch(-1, 1, 1, 1, "Date out of range: -1-1-1-1"));
+  EXPECT_NO_THROW(
+      daysSinceEpoch(292278995, 1, 1, 1, "Date out of range: 292278995-1-1-1"));
+  EXPECT_NO_THROW(
+      daysSinceEpoch(2024, 0, 1, 1, "Date out of range: 2024-0-1-1"));
+  EXPECT_NO_THROW(
+      daysSinceEpoch(2024, 13, 1, 1, "Date out of range: 2024-13-1-1"));
+  EXPECT_NO_THROW(
+      daysSinceEpoch(2024, 1, 6, 1, "Date out of range: 2024-1-6-1"));
+  EXPECT_NO_THROW(
+      daysSinceEpoch(2024, 2, 1, 1, "Date out of range: 2024-2-1-1"));
+  EXPECT_NO_THROW(
+      daysSinceEpoch(2024, 2, 5, 5, "Date out of range: 2024-2-5-5"));
+}
+
 TEST(DateTimeUtilTest, fromDateString) {
   for (ParseMode mode : {ParseMode::kPrestoCast, ParseMode::kSparkCast}) {
     EXPECT_EQ(0, parseDate("1970-01-01", mode));