7617: Add getter/setter assists r=Veykril a=yoshuawuyts
This patch makes progress towards the design outlined in https://github.com/rust-analyzer/rust-analyzer/issues/5943, and includes a small refactor which closes https://github.com/rust-analyzer/rust-analyzer/issues/7607. All together this patch does 4 things:
- Adds a `generate_getter` assist.
- Adds a `generate_getter_mut` assist.
- Adds a `generate_setter` assist.
- Moves the `generate_impl_text` function from `generate_new` into `utils` (which closes#7607).
## Design Notes
I've chosen to follow the [Rust API guidelines on getters](https://rust-lang.github.io/api-guidelines/naming.html#getter-names-follow-rust-convention-c-getter) as closely as possible. This deliberately leaves "builder pattern"-style setters out of scope.
Also, similar to https://github.com/rust-analyzer/rust-analyzer/pull/7570 this assist generates doc comments. I think this should work well in most cases, and for the few where it doesn't it's probably easily edited. This makes it slightly less correct than the #7570 implementation, but I think this is still useful enough to include for many of the same reasons.
The reason why this PR contains 3 assists, rather than 1, is because each of them is so similar to the others that it felt more noisy to do them separately than all at once. The amount of code added does not necessarily reflect that, but hope that still makes sense.
## Examples
**Input**
```rust
struct Person {
name: String, // <- cursor on "name"
}
```
**generate getter**
```rust
struct Person {
name: String,
}
impl Person {
/// Get a reference to the person's name.
fn name(&self) -> &String {
&self.name
}
}
```
**generate mut getter**
```rust
struct Person {
name: String,
}
impl Person {
/// Get a mutable reference to the person's name.
fn name_mut(&mut self) -> &mut String {
&mut self.name
}
}
```
**generate setter**
```rust
struct Person {
name: String,
}
impl Person {
/// Set the person's name.
fn set_name(&mut self, name: String) {
self.name = name;
}
}
```
Co-authored-by: Yoshua Wuyts <yoshuawuyts+github@gmail.com>
7572: Add `find_or_create_impl_block` to assist utils r=matklad a=yoshuawuyts
This is another continuation of https://github.com/rust-analyzer/rust-analyzer/pull/7562, introducing a small util to either find an `impl` block, or create a new one if none exists. I copied this code from the `generate_new` assist into https://github.com/rust-analyzer/rust-analyzer/pull/7562, and this unifies both into a helper.
It doesn't feel super polished in its current state, but my hope is that this is enough of a starting point that it can be expanded on later. For example something that would be useful would be a flag which either returns the index of the start of the block, or the end of the block.
Anyway, I hope this is useful. Thanks!
Co-authored-by: Yoshua Wuyts <yoshuawuyts@gmail.com>
