Breaking changes in dart 2.19

[bsutton]

This might be a bit late to the party, but I"m concerned about a number of breaking changes in dart 2.19

File.create
CastError
path change from pub.dartlang.org to pub.dev

When I first became aware of the above changes (well the last one I only encountered today) I didn't realise the impact nor how close to a 3.0 release we are.

I primarily build CLI apps (and maintain the DCli package). I've now encountered problems (in the wild) with the above changes breaking apps.
I do wonder, given how close we are to a 3.x release, whether these breaking changes should have been left to the 3.x release.

I've largely worked around the issues but worry it might have an extensive impact on the other CLI apps published via pub.dev.

[mraleph]

I think there is no way we can unroll any of these changes. The release process for 2.19 and corresponding Flutter release is basically almost done.

File.create change is in 2.19 since August and had been propagated into Flutter's beta. Removing it now would require breaking change again. It's a non-starter.

CastError

I am not sure about CastError removal. This is supposed to be 3.0 specific change and should not be 2.19 AFAIK. Can you clarify?

path change from pub.dartlang.org to pub.dev

Can you clarify what this refers to? I would assume that the hostname pub talks too is an implementation detail. Similarly anything in .pub_cache is an implementation detail. So if pub changes pub.dartlang.org to pub.dev somewhere it is not a breaking change per se.

/cc @mit-mit

[lrhn]

CastError was changed a little in 2.19. Changelog says:

• The class CastError is deprecated, and all implementation specific classes implementing TypeError or CastError now implement both. In a future release, CastError will be removed. See issue [Breaking Change Request] Deprecate CastError, make everything a TypeError. #40763 for details.

The deprecation is not breaking, and the type change shouldn't be, so I'd also like to know what problems it has caused, in case it's something we can reasonably fix instead of waiting for 3.0 where CastError is removed.

If code depends on a CastError or TypeError being thrown, they still will. If code depends on a CastError or TypeError not being thrown where the other one is, it might become confused, but we do not consider it a breaking change to change the behavior of code which throw an error.

(We still have a problem with the text message of cast errors, but that's cosmetic.)

[mit-mit]

I've now encountered problems (in the wild) with the above changes breaking apps.

More concrete details about these would be appreciated.

[mit-mit]

@bsutton can you please respond with further information? If not, we'll have to close this issue as not actionable...

[bsutton]

Close it out. I do think File.create is going to be somewhat disruptive but it is what it is. My statement about CastError was incorrect - I"ve been playing with dart 2.12, 2.18, 2.19 and 3.x this week and got my wires crossed.

path change from pub.dartlang.org to pub.dev

I was referring to the directory structure of the .pub-cache I have code that compiles a cli package directly from .pub-cache and the dcli library has apis that let users ask questions like 'is package X installed' 'is package x globally activated'. To implement this I scan the .pub-cache directory structure. This change will probably only affect fairly specialised packages like dcli.

…

On Sat, Jan 14, 2023 at 1:58 AM Michael Thomsen ***@***.***> wrote: @bsutton <https://github.com/bsutton> can you please respond with further information? If not, we'll have to close this issue as not actionable... — Reply to this email directly, view it on GitHub <#50953 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AAG32OFSU76FBES4PCEXDT3WSFUS5ANCNFSM6AAAAAATU2DRJE> . You are receiving this because you were mentioned.Message ID: ***@***.***>

[lrhn]

Thanks. 😄
The CastError removal will probably be disruptive when 3.0 lands, but probably also not the biggest change.