The previous analysis was top-down, and worked on a single file (expanding macros). The new analysis is bottom-up, starting from the diagnostics and climbing up the syntax and module tree.
While this is more efficient (and in fact, efficiency was the motivating reason to work on this), unfortunately the code was already fast enough. But luckily, it also fixes a correctness problem: outline parent modules' attributes were not respected for the previous analysis. Case lints specifically did their own analysis to accommodate that, but it was limited to only them. The new analysis works on all kinds of lints, present and future.
It was basically impossible to fix the old analysis without rewriting it because navigating the module hierarchy must come bottom-up, and if we already have a bottom-up analysis (including syntax analysis because modules can be nested in other syntax elements, including macros), it makes sense to use only this kind of analysis.
Few other bugs (not fundamental ti the previous analysis) are also fixed, e.g. overwriting of lint levels (i.e. `#[allow(lint)] mod foo { #[warn(lint)] mod bar; }`.
internal: Replace once_cell with std's recently stabilized OnceCell/Lock and LazyCell/Lock
This doesn't get rid of the once_cell dependency, unfortunately, since we have dependencies that use it, but it's a nice to do cleanup. And when our deps will eventually get rid of once_cell we will get rid of it for free.
This doesn't get rid of the once_cell dependency, unfortunately, since we have dependencies that use it, but it's a nice to do cleanup. And when our deps will eventually get rid of once_cell we will get rid of it for free.
feat: add preliminary support for `+ use<..>` `precise_capturing` syntax
## Summary
This PR adds basic support for the following syntax.
```rs
fn captures<'a: 'a, 'b: 'b, T>() -> impl Sized + use<'b, T> {}
// ~~~~~~~~~~~~~~~~~~~~~~~
// This opaque type does not capture `'a`.
fn outlives<'o, T: 'o>(_: T) {}
fn caller<'o, 'a, 'b: 'o, T: 'o>() {
// ~~
// ^ Note that we don't need `'a: 'o`.
outlives::<'o>(captures::<'a, 'b, T>());
}
```
Related to #17598
Clean up a few minor refs in `format!` macro, as it has a performance cost. Apparently the compiler is unable to inline `format!("{}", &variable)`, and does a run-time double-reference instead (format macro already does one level referencing). Inlining format args prevents accidental `&` misuse.
handle {self} when removing unused imports
Fixes#17139
On master
```rs
mod inner {
pub struct X();
pub struct Y();
}
mod z {
use super::inner::{self, X}$0;
fn f() {
let y = inner::Y();
}
}
```
becomes
```rs
mod inner {
pub struct X();
pub struct Y();
}
mod z {
use super::inner:self;
fn f() {
let y = inner::Y();
}
}
```
with this fix it instead becomes
```
```rs
mod inner {
pub struct X();
pub struct Y();
}
mod z {
use super::inner;
fn f() {
let y = inner::Y();
}
}
```
Before this commit `UseTree::remove_unnecessary_braces` removed the braces
around `{self}` in `use x::y::{self};` but `use x::y::self;` is not valid
rust.
Separate into create and apply edit
Rename usages
Hacky name map
Add more tests
Handle non-exhaustive
Add some more TODOs
Private fields
Use todo
Nesting
Improve rest token generation
Cleanup
Doc -> regular comment
Support mut
