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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 - 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. All values except for "January" and "PM" are invalid and make no sense, 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.

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 2012 Microsoft Azure outage caused by the server trying to generate a certificate valid until February 29, 2013.

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.

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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