Implement lint against unexpected unary precedence

[Urgau]

This PR implements a lint against unexpected unary precedence with a literal and method calls.

ambiguous_unary_precedence

(deny-by-default)

The ambiguous_unary_precedence lint checks for use the negative unary operator with a literal and method calls.

Example

-1i32.abs(); // equals -1, while `(-1i32).abs()` equals 1

Explanation

Unary operations take precedence on binary operations and method calls take precedence over unary precedence. Setting the precedence explicitly makes the code clearer and avoid potential bugs.

---

Note: This is a strip down version of #117161, without the binary op precedence.

Fixes #117155
@rustbot labels +I-lang-nominated
cc @scottmcm
r? compiler

[rustbot]

Some changes occurred in src/tools/clippy

cc @rust-lang/clippy

[bors]

☔ The latest upstream changes (presumably #120393) made this pull request unmergeable. Please resolve the merge conflicts.

[traviscross]

@rustbot labels -I-lang-nominated

Let's remove the nomination here in favor of the one on #117161.

[traviscross]

@rustbot labels +I-lang-nominated

Thanks to discussion with @Urgau, I now notice that this is in fact proposing a subset of #117161 and so should be separately considered (though still probably should be discussed in the same breath). Let's renominate on that basis.

[scottmcm]

I'm (unsurprisingly) a fan of having a lint like this.

For triage discussion: do we want it called unary like this, or maybe ambiguous_literal_precedence?