When viewing traces, it's slightly confusing when the span name doesn't
match the function name. Ensure the names are consistent.
(It might be worth moving most of these to use #[tracing::instrument]
so the name can never go stale. @davidbarsky suggested that is marginally
slower, so I've just done the simple change here.)
feature: Make generate function assist generate a function as a constructor if the generated function has the name "new" and is an asscociated function.
close#17050
This PR makes `generate function assist` generate a function as a constructor if the generated function has the name "new" and is an asscociated function.
If the asscociate type is a record struct, it generates the constructor like this.
```rust
impl Foo {
fn new() -> Self {
Self { field_1: todo!(), field_2: todo!() }
}
}
```
If the asscociate type is a tuple struct, it generates the constructor like this.
```rust
impl Foo {
fn new() -> Self {
Self(todo!(), todo!())
}
}
```
If the asscociate type is a unit struct, it generates the constructor like this.
```rust
impl Foo {
fn new() -> Self {
Self
}
}
```
If the asscociate type is another adt, it generates the constructor like this.
```rust
impl Foo {
fn new() -> Self {
todo!()
}
}
```
Have Derive Attribute share a token tree with it's proc macros.
The goal of this PR is to stop creating a token tree for each derive proc macro.
This is done by giving the derive proc macros an id to its parent derive element.
From running the analysis stat on the rust analyzer project I did see a small memory decrease.
```
Inference: 42.80s, 362ginstr, 591mb
MIR lowering: 8.67s, 67ginstr, 291mb
Mir failed bodies: 18 (0%)
Data layouts: 85.81ms, 609minstr, 8mb
Failed data layouts: 135 (6%)
Const evaluation: 440.57ms, 5235minstr, 13mb
Failed const evals: 1 (0%)
Total: 64.16s, 552ginstr, 1731mb
```
After Change
```
Inference: 40.32s, 340ginstr, 593mb
MIR lowering: 7.95s, 62ginstr, 292mb
Mir failed bodies: 18 (0%)
Data layouts: 87.97ms, 591minstr, 8mb
Failed data layouts: 135 (6%)
Const evaluation: 433.38ms, 5226minstr, 14mb
Failed const evals: 1 (0%)
Total: 60.49s, 523ginstr, 1680mb
```
Currently this breaks the expansion for the actual derive attribute.
## TODO
- [x] Pick a better name for the function `smart_macro_arg`
