make sure checked type implements Try trait when linting [question_mark]

[J-ZhengLi]

(indirectly) fixes: #12412 and fixes: #11983

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changelog: make sure checked type implements Try trait when linting [question_mark]

[rustbot]

r? @Alexendoo

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[m-rph]

Does this pattern come up often? I think I have seen something like this before. Perhaps we could have this in the utils mod.

[Alexendoo]

cx.tcx.lang_items.something().map_or(false, |id| some_util(...)) comes up fairly often, some utils have different variants that take lang items or diagnostic names, maybe we could do something like

trait Definition {
    fn def_id(&self) -> Option<DefId>;
}

And impl it for DefId, LangItem, Symbol (for diagnostic names)

Then you could do implements_trait(..., LangItem::Try) or implements_trait(.., sym::Default). Could use it to get unify a good few utils, but things taking a trait is going to be slightly more difficult to understand

[Alexendoo]

Thanks! @bors r+

[bors]

📌 Commit 91f3fad has been approved by Alexendoo

It is now in the queue for this repository.

[bors]

⌛ Testing commit 91f3fad with merge e0e7ee1...

[bors]

☀️ Test successful - checks-action_dev_test, checks-action_remark_test, checks-action_test
Approved by: Alexendoo
Pushing e0e7ee1 to master...