Allow more lazy evaluations

[dylni]

Update unnecessary_lazy_evaluations to allow closures for trivial functions according to the developer's preference.

The current list of trivial functions is is_empty, len, and as_*. This list cannot be updated without causing churn, because e.g., calls to unwrap_or_else and unwrap_or would need to be swapped for each addition and removal. This list is also undocumented and not based on actual method complexity, but repositories need to follow it to be compliant with this default lint. Leaving these trivial functions up to developer preference allows developers to not need to think about which functions Clippy considers lazy.

A configuration could be added later to re-enable this without any backward-compatibility concern, but it should not be enforced by default.

changelog: [unnecessary_lazy_evaluations]: allow optional closure for trivial functions

Fixes: #8109

[rustbot]

r? @Jarcho

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[github-actions]

Lintcheck changes for de1028a

Lint	Added	Removed	Changed
clippy::if_then_some_else_none	0	0	3
clippy::option_if_let_else	0	0	2
clippy::unnecessary_lazy_evaluations	0	12	0

This comment will be updated if you push new changes

[rustbot]

☔ The latest upstream changes (possibly e1130b6) made this pull request unmergeable. Please resolve the merge conflicts.

[Jarcho]

This is not a good way to fix unnecessary_lazy_evaluations. The eager_or_lazy check is used by a lot a lints that will have a regression.

This is not saying there's nothing to fix here. unnecessary_lazy_evaluations should be far less aggressive in general, but it needs to be something targeted at that lint in particular.