Timezone-induced test failures on CI

When updating #361, I experienced an odd issue – a few tests were failing on master (not my own branch!) for no clear reason. Here’s the summary:

Summary of all failing tests FAIL test/en/en_relative.test.ts (9.746 s) ● Test - Relative date components’ certainty

expect(received).toBe(expected) // Object.is equality

Expected: -240
Received: -300

  155 |         expect(result.start.get("day")).toBe(7);
  156 |         expect(result.start.get("hour")).toBe(12);
> 157 |         expect(result.start.get("timezoneOffset")).toBe(refDate.getTimezoneOffset() * -1);
      |                                                    ^
  158 | 
  159 |         expect(result.start.isCertain("year")).toBe(true);
  160 |         expect(result.start.isCertain("month")).toBe(true);

  at test/en/en_relative.test.ts:157:52
  at Object.<anonymous> (test/en/en_relative.test.ts:151:5)

● Test - Relative date components’ certainty and imply timezone

Expected date to be: Mon Nov 30 2020 11:00:00 GMT-0500 (GMT-05:00) Received: Sun Nov 29 2020 11:00:00 GMT-0500 (GMT-05:00) ([ParsingResult {index: 0, text: 'tomorrow at 5pm', ...}])

  186 |         result.start.imply("timezoneOffset", 60);
  187 | 
> 188 |         expect(result).toBeDate(new Date("Sun Dec 1 2020 1:00:00 GMT+0900 (Japan Standard Time)"));
      |                        ^
  189 |         expect(result).toBeDate(new Date("Sun Nov 30 2020 17:00:00 GMT+0100"));
  190 |     }
  191 | 

  at Object.<anonymous> (test/en/en_relative.test.ts:188:24)

This is current master, which is at commit 6daa27d. I’m on Node v14.15.1.

Most oddly, I rebased PR #361 on top of that commit, and didn’t make any changes that should affect tests, but they pass on Travis instead of failing.

[ptz0n]

Yep, fragile test assertion. First one mentioned above is fixed in #368.

[wanasit]

With refDate as normal Date object, the refDate’s timezone information will be lost and we cannot really calculate the precise relative time without assuming it’s the same timezone as the system. Maybe in the future major release we should let people pass refTimezone or refDate as string.

For now, I am thinking we should remove that close to mid-night checking logic (minor release 2.2+). I don’t really think that logic is that helpful anyway. I’ll do that sometime this weekend.

Please let me know what you think.