DateFormatter bug

Hi, all.

I have found a weird result of DateFormatter.
Check out the code below.

let formatter = DateFormatter()

formatter.dateFormat = "yyyyMMdd" "20220101") // 2022. 01. 01 "") // 2000. 01. 01 " ") // nil

I thnk passing empty string to DateFormatter should return nil like " ", but instead It returns the first day of 2000.

It it a bug or not?


Dong hyun Hwang

1 Like

It it a bug or not?

Regardless of this empty string issue, I want to highlight another couple of gotchas with DateFormatter:

  • Setting a fixed date format without also pinning the locale to en_US_POSIX will result in obscure bugs that likely only show up once you’ve deployed your app. See QA1480 NSDateFormatter and Internet Dates for more background on this.

  • Parsing dates without times is another source of bugs that only show up in the field. See my Parsing Dates Without Times post on DevForums.

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Quinn “The Eskimo!” @ DTS @ Apple