Fix temporal ITs to only generate DST-safe time

Randomized tests for `DateTime` Cypher type generate random date-time
values with time zone (either offset or id). They used to be flaky
because sometimes generated instant was invalid. Such instant pointed
to a non-existing time during a Daylight Saving Time adjustment/jump.
Such time values are adjusted to the nearest valid value by the
database. This made tests fail because received value was different
from the sent value.

This commit fixes the problem by making random `DateTime` generator
never generate hour of the day that is in the DST adjustment range. It
also reduces the number of test time zones to couple popular ones. This
is done to make sure all tested time zones are supported by the JVM,
neo4j database is running on.

Author: lutovich

test/v1/temporal-types.test.js

@@ -32,13 +32,7 @@ const MIN_TIME_ZONE_OFFSET = -MAX_TIME_ZONE_OFFSET;
 const SECONDS_PER_MINUTE = 60;
 const MIN_ZONE_ID = 'Etc/GMT+12';
 const MAX_ZONE_ID = 'Etc/GMT-14';
-const ZONE_IDS = ['Europe/Zaporozhye', 'America/Argentina/Mendoza', 'Etc/GMT-12', 'Asia/Jayapura', 'Pacific/Auckland', 'America/Argentina/Rio_Gallegos',
-  'America/Tegucigalpa', 'Europe/Skopje', 'Africa/Lome', 'America/Eirunepe', 'Pacific/Port_Moresby', 'America/Merida', 'Asia/Qyzylorda', 'Hongkong',
-  'America/Paramaribo', 'Pacific/Wallis', 'Antarctica/Mawson', 'America/Metlakatla', 'Indian/Reunion', 'Asia/Chungking', 'Canada/Central', 'Etc/GMT-6',
-  'UCT', 'America/Belem', 'Europe/Belgrade', 'Singapore', 'Israel', 'Europe/London', 'America/Yellowknife', 'Europe/Uzhgorod', 'Etc/GMT+7',
-  'America/Indiana/Winamac', 'Asia/Kuala_Lumpur', 'America/Cuiaba', 'Europe/Sofia', 'Asia/Kuching', 'Australia/Lord_Howe', 'America/Porto_Acre',
-  'America/Indiana/Indianapolis', 'Africa/Windhoek', 'Atlantic/Cape_Verde', 'Asia/Kuwait', 'America/Barbados', 'Egypt', 'GB-Eire', 'Antarctica/South_Pole',
-  'America/Kentucky/Louisville', 'Asia/Yangon', 'CET', 'Etc/GMT+11', 'Asia/Dubai', 'Europe/Stockholm'];
+const ZONE_IDS = ['Europe/Zaporozhye', 'Europe/London', 'UTC', 'Africa/Cairo'];
 
 describe('temporal-types', () => {
 
@@ -434,18 +428,22 @@ describe('temporal-types', () => {
 
   function randomDateTimeWithZoneOffset() {
     return new neo4j.DateTimeWithZoneOffset(
-      randomLocalDateTime(),
+      randomDstSafeLocalDateTime(),
       randomZoneOffsetSeconds()
     );
   }
 
   function randomDateTimeWithZoneId() {
     return new neo4j.DateTimeWithZoneId(
-      randomLocalDateTime(),
+      randomDstSafeLocalDateTime(),
       randomZoneId()
     );
   }
 
+  function randomDstSafeLocalDateTime() {
+    return new neo4j.LocalDateTime(randomDate(), randomDstSafeLocalTime());
+  }
+
   function randomLocalDateTime() {
     return new neo4j.LocalDateTime(randomDate(), randomLocalTime());
   }
@@ -474,6 +472,15 @@ describe('temporal-types', () => {
     );
   }
 
+  function randomDstSafeLocalTime() {
+    return new neo4j.LocalTime(
+      randomInt(4, 23), // do not generate hours in range where DST adjustment happens
+      randomInt(0, 59),
+      randomInt(0, 59),
+      randomInt(0, MAX_NANO_OF_SECOND)
+    );
+  }
+
   function randomZoneOffsetSeconds() {
     const randomOffsetWithSeconds = neo4j.int(randomInt(MIN_TIME_ZONE_OFFSET, MAX_TIME_ZONE_OFFSET));
     return randomOffsetWithSeconds.div(SECONDS_PER_MINUTE).multiply(SECONDS_PER_MINUTE); // truncate seconds