Deprecate iterable_contains_unrelated_type and list_remove_unrelated_type

[srawlins]

in favor of collection_methods_unrelated_type

See my proposal to replace those two with the new rule in the lints package: dart-lang/core#787.

The best way to do this would be to ship a lints release with iterable_contains_unrelated_type and list_remove_unrelated_type replaced by collection_methods_unrelated_type, then deprecated them. This would result in less churn.

[pq]

Great point re: less churn. We'll want to be thoughtful about how we time updates to package:lints. (See also: #58947 which proposes we deprecate a few recommended lints.)

[pq]

@srawlins: I'm thinking this is a little close to the wire to pull off?

[srawlins]

Hmm close to what wire? I don't know what is involved with deprecating a lint rule, but it doesn't need to be... associated with any Dart SDK or language version, right? It's not breaking?

[srawlins]

Although in the summary above I mention that the best way forward might be some work in the lints package first, before deprecating. No strong opinions here.

[pq]

Hmm close to what wire?

Sorry, I wasn't clear at all! It was on the list to consider for 3.0. I guess I'd just like to push it to later.

[srawlins]

Sounds good to me.

[srawlins]

@devoncarew mentioned here it should be safe to deprecate first, then remove from package:lints. Mind if I ship that, @pq ?

[pq]

You mean, deprecate these lints here now? Sure thing.

[srawlins]

Sorry, I don't know what the difference is, but I'd like to remove the rules. Is there a reason to deprecate them before removing them?

[pq]

The difference is that a removed lint will no longer work whereas a deprecated one will.

Is there a reason to deprecate them before removing them?

It's a nice way to give folks an opportunity to give feedback (and continue to give them lints before they've adopted the new recommendation).

Unless a lint is deeply broken or made obsolete (e.g., pre-null safety), I'd prefer a deprecation period.

We could add more details here I guess:

https://github.com/dart-lang/linter/blob/main/doc/lint-lifecycle.md#removed

[srawlins]

OK