Fix [unnecessary_lazy_eval] when type has significant drop

[kraktus]

fix for #9427 (comment)

However current implementation gives too many false positive, rending the lint almost useless.

I don't know what's the best way to check if a type has a "significant" drop (in the common meaning, not the internal rustc one, for example Option<(u8, u8)> should not be considered significant)

changelog: Fix [unnecessary_lazy_eval] when type has significant drop

[rust-highfive]

r? @Manishearth

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[Manishearth]

cc @rust-lang/clippy thoughts?

[xFrednet]

I would probably go with the rustc "significant" drop. In most cases, false negatives are better than false positives. But I have no strong opinion on this.

[llogiq]

Yeah, the other benefit of following the rustc definition is that we'll be updated automatically if it ever changed.

[kraktus]

Just to be clear, do you think the current fix would be enough applied as-is? (Documentation apart)

[kraktus]

Should be good to go 👍

[Manishearth]

r? @xFrednet

[xFrednet]

LGTM, thank you for the update and in general all the work you currently do around Clippy. It's really a big help!

@bors r+

[bors]

📌 Commit ed183ee has been approved by xFrednet

It is now in the queue for this repository.

[bors]

⌛ Testing commit ed183ee with merge 5595d7f...

[bors]

☀️ Test successful - checks-action_dev_test, checks-action_remark_test, checks-action_test
Approved by: xFrednet
Pushing 5595d7f to master...