Add normalization rules for time zone offsets

Summary:
When resolving time zone offsets, minutes or the ':' separator may be
omitted (check inline code comments).

Reviewed By: amitkdutta

Differential Revision: D60432366

velox/expression/tests/CastExprTest.cpp

@@ -565,6 +565,8 @@ TEST_F(CastExprTest, stringToTimestamp) {
  "1970-01-01 00:00:00",
  "2000-01-01 12:21:56",
  "1970-01-01 00:00:00-02:00",
+ "1970-01-01 00:00:00 +02",
+ "1970-01-01 00:00:00 -0101",
  std::nullopt,
  };
  std::vector<std::optional<Timestamp>> expected{
@@ -574,6 +576,8 @@ TEST_F(CastExprTest, stringToTimestamp) {
  Timestamp(0, 0),
  Timestamp(946729316, 0),
  Timestamp(7200, 0),
+ Timestamp(-7200, 0),
+ Timestamp(3660, 0),
  std::nullopt,
  };
  testCast<std::string, Timestamp>("timestamp", input, expected);

velox/type/tests/TimestampConversionTest.cpp

@@ -258,6 +258,12 @@ TEST(DateTimeUtilTest, fromTimestampWithTimezoneString) {
  EXPECT_EQ(
  parseTimestampWithTimezone("1970-01-01 00:00:00+13:36"),
  std::make_pair(Timestamp(0, 0), tz::getTimeZoneID("+13:36")));
+ EXPECT_EQ(
+ parseTimestampWithTimezone("1970-01-01 00:00:00 -11"),
+ std::make_pair(Timestamp(0, 0), tz::getTimeZoneID("-11:00")));
+ EXPECT_EQ(
+ parseTimestampWithTimezone("1970-01-01 00:00:00 +0000"),
+ std::make_pair(Timestamp(0, 0), tz::getTimeZoneID("+00:00")));
 
  EXPECT_EQ(
  parseTimestampWithTimezone("1970-01-01 00:00:00Z"),

velox/type/tz/TimeZoneMap.cpp

@@ -110,6 +110,10 @@ inline bool startsWith(std::string_view str, const char* prefix) {
  return str.rfind(prefix, 0) == 0;
 }
 
+inline bool isTimeZoneOffset(std::string_view str) {
+ return str.size() >= 3 && (str[0] == '+' || str[0] == '-');
+}
+
 // The timezone parsing logic follows what is defined here:
 // https://en.wikipedia.org/wiki/List_of_tz_database_time_zones
 inline bool isUtcEquivalentName(std::string_view zone) {
@@ -118,7 +122,36 @@ inline bool isUtcEquivalentName(std::string_view zone) {
  return utcSet.find(zone) != utcSet.end();
 }
 
+// This function tries to apply two normalization rules to time zone offsets:
+//
+// 1. If the offset only defines the hours portion, assume minutes are zeroed
+// out (e.g. "+00" -> "+00:00")
+//
+// 2. Check if the ':' in between in missing; if so, correct the offset string
+// (e.g. "+0000" -> "+00:00").
+//
+// This function assumes the first character is either '+' or '-'.
+std::string normalizeTimeZoneOffset(const std::string& zoneOffset) {
+ if (zoneOffset.size() == 3 && isDigit(zoneOffset[1]) &&
+ isDigit(zoneOffset[2])) {
+ return zoneOffset + ":00";
+ } else if (
+ zoneOffset.size() == 5 && isDigit(zoneOffset[1]) &&
+ isDigit(zoneOffset[2]) && isDigit(zoneOffset[3]) &&
+ isDigit(zoneOffset[4])) {
+ return zoneOffset.substr(0, 3) + ':' + zoneOffset.substr(3, 2);
+ }
+ return zoneOffset;
+}
+
 std::string normalizeTimeZone(const std::string& originalZoneId) {
+ // If this is an offset that hasn't matched, check if this is an incomplete
+ // offset.
+ if (isTimeZoneOffset(originalZoneId)) {
+ return normalizeTimeZoneOffset(originalZoneId);
+ }
+
+ // Otherwise, try other time zone name normalizations.
  std::string_view zoneId = originalZoneId;
  const bool startsWithEtc = startsWith(zoneId, "etc/");
 

velox/type/tz/tests/TimeZoneMapTest.cpp

@@ -182,10 +182,19 @@ TEST(TimeZoneMapTest, getTimeZoneID) {
  // (+/-)XX:MM format.
  EXPECT_EQ(840, getTimeZoneID("-00:01"));
  EXPECT_EQ(0, getTimeZoneID("+00:00"));
+ EXPECT_EQ(0, getTimeZoneID("-00:00"));
  EXPECT_EQ(454, getTimeZoneID("-06:27"));
  EXPECT_EQ(541, getTimeZoneID("-05:00"));
  EXPECT_EQ(1140, getTimeZoneID("+05:00"));
 
+ // Incomplete time zone offsets.
+ EXPECT_EQ(1140, getTimeZoneID("+05"));
+ EXPECT_EQ(1140, getTimeZoneID("+0500"));
+ EXPECT_EQ(1150, getTimeZoneID("+0510"));
+ EXPECT_EQ(181, getTimeZoneID("-1100"));
+ EXPECT_EQ(181, getTimeZoneID("-11"));
+ EXPECT_EQ(0, getTimeZoneID("+0000"));
+
  EXPECT_EQ(0, getTimeZoneID("etc/GMT+0"));
  EXPECT_EQ(0, getTimeZoneID("etc/GMT-0"));
  EXPECT_EQ(1020, getTimeZoneID("etc/GMT-3"));