[WIP] feat: Add DateTimeSecondsSinceEpoch

[KKimj]

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Working-in-progress

Resolve : #59961

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[julemand101]

Do note that static methods cannot be added to classes using extension methods. So what you do here is just declaring a static method on the extension itself and which needs to be called with: DateTimeSecondsSinceEpoch.fromSecondsSinceEpoch which I don't think was your intention.

[mit-mit]

Hi @KKimj are you still working on this?

[KKimj]

Hello! :) @mit-mit
Yes, I'm working on the implementation but waiting for feedback on its necessity.
Also, I'm concerned about minimizing changes and avoiding breaking changes.
Thanks!

[mit-mit]

Hi @KKimj please respond to the comments in the review tool: https://dart-review.googlesource.com/c/sdk/+/405740

[copybara-service]

https://dart-review.googlesource.com/c/sdk/+/405740 has been updated with the latest commits from this pull request.

[copybara-service]

https://dart-review.googlesource.com/c/sdk/+/405740 has been updated with the latest commits from this pull request.

[KKimj]

1. I understand that implementing DateTime.fromSecondsSinceEpoch as a static extension is not a good direction.

2. some concerns:

• Adding DateTime.fromSecondsSinceEpoch will likely introduce breaking changes.
• I would like to separate the PR for int get secondsSinceEpoch and the addition of DateTime.fromSecondsSinceEpoch, if possible.

3. I will add more test cases and improve the test code.

[mit-mit]

Hi @KKimj code reviews for Dart happen in the code review tool, so kindly respond there, not here on github:
https://dart-review.googlesource.com/c/sdk/+/405740

[a-siva]

@KKimj are you still working on addressing the code review comments ?