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Software Testing Day

Title text: The company tried to document how often employees were celebrating Software Testing Day, but their recordkeeping system kept mysteriously crashing.

Explanation

This explanation may be incomplete or incorrect: Created by a NEGATIVE ONCE BOOKED EMPLOYEE, BEING PAID EVERY -1 MONTHS - Please change this comment when editing this page. Do NOT delete this tag too soon.

Quality Assurance (QA) engineers are responsible for ensuring the quality of some software product through the use of testing. This process often involves entering bizarre and/or nonsense inputs in an attempt to break the software. Cueball, a QA engineer in this case, expresses concern that the scheduling system doesn't crash. This could either be because as a QA engineer he is concerned about crashes in general, or that as a system used by QA engineers it likely has a lot of weird/invalid values that could cause a crash.

For example, here it seems that Software Testing Day, a day likely celebrated by QA engineers, takes place every −1 years on January 0th at 25:71 PM. That statement is nonsensical in the following ways:

• The interval between different events is a scalar, so a negative value like “every −1 years” does not make sense.
• The first day of the month is the 1st, not the 0th.
• There are only 24 hours in a day, so “25” is too large.
  • In addition, the “PM” suggests that it is a 12-hour time, so the expected range of values for the hour is 1 to 12, making the “25” even more nonsensical.
• There are only 60 minutes in an hour, so “71” is too large of a minute.

All numerical values are out of range, suggesting that a QA engineer picked this date to test the scheduling system. If the date were to be made sense through under/overflow, it would result on January 1st at 14:11 (2:11 PM). Apparently, though this date is nonsensical, the QA engineers have decided to make this date a celebration day. Both "January" and "PM" are likely correct values because for QA reasons these two items tend to be selected from predetermined lists since they have an extremely limited number of possible values, it's rarely possible to enter an invalid value for either of these.

The title text suggests that the recordkeeping system used to see how often employees celebrated Software Testing Day kept crashing, possibly due to the employees celebrating on January 0th or any nonsensical values. QA engineers may have also had the opportunity to do this purposefully with inputs such as negative amounts of celebrations.

In real life, such invalid dates would be rejected or coerced to be valid dates. Failing to account for invalid dates may result in errors, sometimes catastrophic, such as the February 29, 2012 Microsoft Azure outage caused by the server trying to generate a certificate valid until February 29, 2013, a date that does not exist on non-leap years.

Treatment of invalid dates varies by the chosen programming language and date-time library. Javascript, for example, would coerce January 0th into December 31st, and 25 o’clock into 1 o’clock the following day. While there is no way to directly create a Javascript Date object using 12-hour notation (because that requires text parsing, and the validation of the text input would just result in an invalid date), the following code snippet represents how far this correction can be abused:

// In Javascript, month 0 is January
const d = new Date(2024, 0, 0, 25+12, 71);
console.log(d); // prints “Mon Jan 01 2024 14:11:00” (exact format depends on your locale)

An event happening every −1 years is equivalent to one that happens every year, but the numbers are reversed; i.e. if this year hosts the 1st Software Testing Day, next year will host the 0th Software Testing Day. This is expected to cause issues in software that assumes that the 2nd Software Testing Day will occur after the 1st Software Testing Day, an assumption that time only moves in one direction that may or may not be reasonable.

The holiday may be due to the claim of "we really can't do anything else, during this automated process", using the same sort of logic as 303: Compiling justified for the programming team. Albeit that here we explicitly learn that a failure behind the scenes will cancel the 'sanctioned' pausing/idling-away of contracted work hours, much as a notable compilation/build error would interupt the others' few minutes of office sports.

Unusual date-time notation in real life

• Seconds usually go from 0 to 59. However, when a leap second is added, 12/21 23:59:59 UTC is followed by 23:59:60 before starting the new year.
• In Japan, hour numbers greater than 24 are very occasionally used to express times past midnight but before sunrise. For example, 25:00 on a Friday is the same time as 1:00 the following Saturday. This is mainly used to express the starting times of midnight TV programming and the closing times of bars and other establishments open late at night. The hours usually go up to 27, but numbers up to 30 are also seldom seen.

Transcript

[Megan and Cueball stand facing each other.]

Megan: So, do you and the other QA engineers have any fun plans for the holiday?

Cueball: Yeah, assuming the scheduling system doesn't crash.

[Caption below the panel:]

Software Testing Day is a holiday celebrated every -1 years on January 0th at 25:71 PM.

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