Display a count of 0 when the prep count has not been defined instead of NaN

[CarolineDenis]

Fixes #3881

[maxpatiiuk]

hmm, I didn't look into the code too closely, but NaN is not expected result - it implies that there might be some wrong calculation going on somewhere (either division by 0, or arithmetic on non-numeric data)

please double check where NaN is coming from and correct the issue there

i.e before the calculation that could result in a NaN, add a check to guard against such case, - if such case is detected, then set 0 instead of doing the calculation

tldr: the code change you made is correct, but it is better to prevent NaN from being created rather than changing how NaN is being displayed

small thing, but also prefer using Number.isNaN over isNaN (isNaN is legacy and has some weird behavior that has been fixed in Number.isNaN)

[CarolineDenis]

hmm, I didn't look into the code too closely, but NaN is not expected result - it implies that there might be some wrong calculation going on somewhere (either division by 0, or arithmetic on non-numeric data)

please double check where NaN is coming from and correct the issue there

i.e before the calculation that could result in a NaN, add a check to guard against such case, - if such case is detected, then set 0 instead of doing the calculation

tldr: the code change you made is correct, but it is better to prevent NaN from being created rather than changing how NaN is being displayed

small thing, but also prefer using Number.isNaN over isNaN (isNaN is legacy and has some weird behavior that has been fixed in Number.isNaN)

ok will do that. The NaN comes from the fact that the count has not been defined (the field is just empty). If the user sets it to 0 we would see 0.

[maxpatiiuk]

Better but not quite there. I probably wasn't clear, so let me clarify - NaN should never be created - yes, back-end returns null, but front-end converting that to NaN is not right.

The bug occurs here:

See how line 194 uses Number.parseInt? that results in a NaN, instead, it should use f.parseInt(prepData[10] ?? undefined) ?? 0 like previous lines

---

for why I (and the JS community in general) are about trying to avoid NaNs as much as possible see any of the following:

• https://stackoverflow.com/questions/43580225/comparison-with-nan-doesnt-work-the-way-i-expect
• https://medium.com/codex/javascripts-nan-is-dumbass-661a3a8e8d1a
• https://ntgard.medium.com/why-nan-nan-3d41af988d30
• https://blog.webdevsimplified.com/2020-10/javascript-nan/
• https://levelup.gitconnected.com/dont-fall-into-the-nan-trap-d2fbc5536e50

[bronwyncombs]

working!

Screen.Recording.2023-09-27.at.3.24.20.PM.mov

Screen.Recording.2023-09-27.at.3.29.01.PM.mov