fix: Correct dayOfWeek letter for SimpleDateTimeFormatter (facebookincubator#15517)

Summary:
In Velox, `e` was incorrectly used as the `dayOfWeek` letter in `SimpleDateTimeFormatter`.

https://github.com/facebookincubator/velox/blob/974e77c1271369755f89825a120c2a1265bf879e/velox/functions/lib/DateTimeFormatter.cpp#L2023-L2025

This PR fixes this by using the letter `u` to be consistent with Java.
https://docs.oracle.com/en/java/javase/11/docs/api/java.base/java/text/SimpleDateFormat.html

Closes facebookincubator#15516.

Pull Request resolved: facebookincubator#15517

Reviewed By: kKPulla

Differential Revision: D87597881

Pulled By: kagamiori

fbshipit-source-id: fa12bc406d96523abdb20e7e268d94b4af38155e

Author: wForget

velox/functions/lib/DateTimeFormatter.cpp

@@ -2020,7 +2020,7 @@ Expected<std::shared_ptr<DateTimeFormatter>> buildSimpleDateTimeFormatter(
         case 'D':
           builder.appendDayOfYear(count);
           break;
-        case 'e':
+        case 'u':
           builder.appendDayOfWeek1Based(count);
           break;
         case 'E':

velox/functions/lib/tests/DateTimeFormatterTest.cpp

@@ -2368,16 +2368,16 @@ TEST_F(SimpleDateTimeFormatterTest, parseSimpleWeekOfMonth) {
     // Format contains year, month, weekOfMonth and dayOfWeek.
     EXPECT_EQ(
         fromTimestampString("2024-08-02"),
-        parseSimple("2024 08 01 5", "yyyy MM WW e", lenient).timestamp);
+        parseSimple("2024 08 01 5", "yyyy MM WW u", lenient).timestamp);
     EXPECT_EQ(
         fromTimestampString("2024-08-03"),
-        parseSimple("2024 08 01 6", "yyyy MM WW e", lenient).timestamp);
+        parseSimple("2024 08 01 6", "yyyy MM WW u", lenient).timestamp);
     EXPECT_EQ(
         fromTimestampString("2024-08-09"),
-        parseSimple("2024 08 02 5", "yyyy MM WW e", lenient).timestamp);
+        parseSimple("2024 08 02 5", "yyyy MM WW u", lenient).timestamp);
     EXPECT_EQ(
         fromTimestampString("2024-08-12"),
-        parseSimple("2024 08 03 1", "yyyy MM WW e", lenient).timestamp);
+        parseSimple("2024 08 03 1", "yyyy MM WW u", lenient).timestamp);
 
     // Format contains year, month and weekOfMonth.
     EXPECT_EQ(
@@ -2398,25 +2398,25 @@ TEST_F(SimpleDateTimeFormatterTest, parseSimpleWeekOfMonth) {
   // Field out of range for lenient mode.
   EXPECT_EQ(
       fromTimestampString("2024-09-30"),
-      parseSimple("2024 08 10 1", "yyyy MM WW e", true).timestamp);
+      parseSimple("2024 08 10 1", "yyyy MM WW u", true).timestamp);
   EXPECT_EQ(
       fromTimestampString("2024-07-28"),
       parseSimple("2024 08 01", "yyyy MM WW", true).timestamp);
   EXPECT_EQ(
       fromTimestampString("2025-02-24"),
-      parseSimple("2024 15 01 1", "yyyy MM WW e", true).timestamp);
+      parseSimple("2024 15 01 1", "yyyy MM WW u", true).timestamp);
   EXPECT_EQ(
       fromTimestampString("2024-07-29"),
-      parseSimple("2024 08 01 9", "yyyy MM WW e", true).timestamp);
+      parseSimple("2024 08 01 9", "yyyy MM WW u", true).timestamp);
 
   // Field out of range for strict mode.
   EXPECT_THROW(
-      parseSimple("2024 08 10 1", "yyyy MM WW e", false), VeloxUserError);
+      parseSimple("2024 08 10 1", "yyyy MM WW u", false), VeloxUserError);
   EXPECT_THROW(parseSimple("2024 08 10", "yyyy MM WW", false), VeloxUserError);
   EXPECT_THROW(
-      parseSimple("2024 15 01 1", "yyyy MM WW e", false), VeloxUserError);
+      parseSimple("2024 15 01 1", "yyyy MM WW u", false), VeloxUserError);
   EXPECT_THROW(
-      parseSimple("2024 08 01 9", "yyyy MM WW e", false), VeloxUserError);
+      parseSimple("2024 08 01 9", "yyyy MM WW u", false), VeloxUserError);
 }
 
 TEST_F(SimpleDateTimeFormatterTest, formatResultSize) {