Lint against empty cfg(any()/all())

[clubby789]

Detect usages of cfg(any()) and cfg(all()) and suggest the literal boolean equivalents. When --lint-rust-version is available, gate the diagnostic appropriately.
Will need to be updated for #158134

Implements the lint suggested in rust-lang/rfcs#3695 (Tracking: #131204)
Tracking issue: #157574

[rustbot]

Some changes occurred in compiler/rustc_attr_parsing

cc @jdonszelmann, @JonathanBrouwer

[rustbot]

r? @Kivooeo

rustbot has assigned @Kivooeo.
They will have a look at your PR within the next two weeks and either review your PR or reassign to another reviewer.

Use r? to explicitly pick a reviewer

Why was this reviewer chosen?

The reviewer was selected based on:

• Owners of files modified in this PR: compiler
• compiler expanded to 73 candidates
• Random selection from 19 candidates

[rustbot]

miri is developed in its own repository. If possible, consider making this change to rust-lang/miri instead.

cc @rust-lang/miri

[mejrs]

Does this lint fire if the cfg predicate is produced in a macro expansion? I can see some valid use cases for producing all() etc in a macro.

[clubby789]

Does this lint fire if the cfg predicate is produced in a macro expansion? I can see some valid use cases for producing all() etc in a macro.

No;

if list.is_empty() && !list.span.from_expansion() {

gates the emission.

[rustbot]

clippy is developed in its own repository. If possible, consider making this change to rust-lang/rust-clippy instead.

cc @rust-lang/clippy

[clubby789]

This does overlap somewhat with clippy::non_minimal_cfg

[rustbot]

Reminder, once the PR becomes ready for a review, use @rustbot ready.

[rustbot]

This PR was rebased onto a different main commit. Here's a range-diff highlighting what actually changed.

Rebasing is a normal part of keeping PRs up to date, so no action is needed—this note is just to help reviewers.

[JonathanBrouwer]

r=me after T-lang approves

View changes since this review

[traviscross]

Suggested change

	pub EMPTY_CFG_PREDICATE,
	pub EMPTY_CFG_PREDICATES,

Per our RFC 0344 guidance, this should be in the plural.

Also, the naming seems a bit loose. This is targeting two specific cfg predicates, not empty cfg predicates in general (and, of course, we might later add more cfg predicates that we might not want to lint when empty). Have any more targeted ideas for a name?

View changes since the review

[clubby789]

Maybe EMPTY_CFG_COMBINATORS? Or EMPTY_CFG_LISTS (but that's a little less precise)

[ada4a]

Or MANUAL_CFG_BOOL?