Remove `Session::one_time_diagnostic`
This is untracked mutable state, which modified the behaviour of queries.
It was used for 2 things: some full-blown errors, but mostly for lint declaration notes ("the lint level is defined here" notes).
It is replaced by the diagnostic deduplication infra which already exists in the diagnostic emitter.
A new diagnostic level `OnceNote` is introduced specifically for lint notes, to deduplicate subdiagnostics.
As a drive-by, diagnostic emission takes a `&mut` to allow dropping the `SubDiagnostic`s.
Changelog for Rust 1.60.0 🦀 (Kudos to everyone who contributed!)
As always, I'm impressed by how much stuff happened in just one release. Seriously, kudos to everyone who contributed.
changelog: none
fix suggestion on `[map_flatten]` being cropped causing possible information loss
fixes#8506
Multi-line suggestion given by the lint is missing its bottom part, which could potentially contains useful information about the fix.
---
changelog: [`map_flatten`]: Long suggestions will now be splitup into two help messages
[generator_interior] Be more precise with scopes of borrowed places
Previously the generator interior type checking analysis would use the nearest temporary scope as the scope of a borrowed value. This ends up being overly broad for cases such as:
```rust
fn status(_client_status: &Client) -> i16 {
200
}
fn main() {
let client = Client;
let g = move || match status(&client) {
_status => yield,
};
assert_send(g);
}
```
In this case, the borrow `&client` could be considered in scope for the entirety of the `match` expression, meaning it would be viewed as live across the `yield`, therefore making the generator not `Send`.
In most cases, we want to use the enclosing expression as the scope for a borrowed value which will be less than or equal to the nearest temporary scope. This PR changes the analysis to use the enclosing expression as the scope for most borrows, with the exception of borrowed RValues which are true temporary values that should have the temporary scope. There's one further exception where borrows of a copy such as happens in autoref cases also should be ignored despite being RValues.
Joint work with `@nikomatsakis`
Fixes#57017
r? `@tmandry`
