Bumped up Dart min version to 3.0.0 for json_serializable

[al-kimmel-serj]

Bumped up Dart min version to 3.0.0 for json_serializable, because json_serializable requires Dart 3.5 since 6.9.0.

Error out about bump up Dart version has been added to json_serializable release 6.9.3

@jaumard @josh-burton @amondnet @sbu-WBT @kuhnroyal @agilob @ahmednfwela, could you review my PR?

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[wing328]

thanks for the PR

please follow step 3 to update the samples.

[al-kimmel-serj]

thanks for the PR

please follow step 3 to update the samples.

@wing328, thank you. I've updated samples in PR.

[wing328]

thanks for the PR

does it mean the output (dart API client) no longer work with Dart 2.x?

[al-kimmel-serj]

Yes. I use json_serializable as serializationLibrary and I see error when I try to generate code via dart run build_runner build with json_serializable:6.9.0. Here is example of error:

line 18, column 30 of .: Expected to find ')'.
   ╷
18 │         if (instance.message case final value?) 'message': value,
   │                              ^^^^
   ╵

json_serializable generates code with case clauses in if statements since 6.9.0.

[wing328]

what about adding an option supportDart2 (default to false) for backward compatibility?

we can't ship a change that breaks all Dart 2.x users.

[al-kimmel-serj]

Yes. I will add the option to PR.

[al-kimmel-serj]

@wing328, I've pushed code for supporting Dart 2.x.

[wing328]

thanks. i'll take another look

[JohnGalt1717]

Hope this gets merged soon. It's a major pain right now.

[al-kimmel-serj]

#20625

[kuhnroyal]

I don't understand why this is needed. Darts dependency resolution should take care of this, no versions are forced by the template. If you use Dart 3.5 and a matching json_serializable version everything should work.

[kuhnroyal]

Also duplicate of #20460

[al-kimmel-serj]

I don't understand why this is needed. Darts dependency resolution should take care of this, no versions are forced by the template. If you use Dart 3.5 and a matching json_serializable version everything should work.

@kuhnroyal, dart build_runner behaves differently. It uses minimal version of dart defined in target package pubspec.yaml.

[kuhnroyal]

Ah ok I see. In any case, this was then fixed by #20460

[al-kimmel-serj]

Ah ok I see. In any case, this was then fixed by #20460

Yes. But I don't see dart2 support in #20460 (backward compatibility) which @wing328 asked me to add to this PR.

[kuhnroyal]

I don't think the fallback is needed. I am just now in the process of dropping 2.x support in dio. And as I understand from this comment (#20460 (comment)) it doesn't work anyway.

[mikefaille]

I don't understand why this is needed. Darts dependency resolution should take care of this, no versions are forced by the template. If you use Dart 3.5 and a matching json_serializable version everything should work.

Visit this issue first showing the problem is very obscure without dependency error or automatics resolution:
#16117

Also, for you and others visiting this PR, I suggest to read my answer here :

#20460 (comment)

[al-kimmel-serj]

Ok. If backward compatibility is not required yet, then I close this PR, because #20460 has already fixed problem.

[mikefaille]

For future reference or if we want to gives some love to this PR later, if we really want to support >=dart2.x to <dart3.5 this PR can still be useful.

But, I suggest to default on >=dart3.5.

Calling the flag : useDartLegacy
Referring to dart 3.5 and less as legacy will reflect the current state of libs compatibility but also the current dart support by the community.

If only they didn't suspended the macros inside the Dart's build_runner https://dart.dev/language/macros
That would simplify the life for an end-user.

That said, I'm embarrassed to say how much time I lost before I figured out the solution with my PR #20460. So, please build over and don't revert for anyone who wants to use openapi-generator with a new Dart project.

[JohnGalt1717]

The fundamental issue here is that json_serializable made a significant dependency change outside of a major version number, which shouldn't have happened.

If someone still cares about dart 2.0 then this PR is useful but it would also have to lower to a major version of json_serializable etc. to make it work with dart 2.0 as a result.

[mikefaille]

That said, lowering json_serializable will force to lower json_annotation which force to use an old dart dio version. Then, dart-dio generator for openapi will be stuck in very old version of Dio.

I think json_annotation is the root cause.

[kuhnroyal]

@mikefaille I agree, and with the focus of maintainability I am always in favor of dropping older versions. We all only have limited time to work on these open source projects.