4083: Smol documentation for ast nodes r=matklad a=Veetaha
There is a tremendous amount of TODOs to clarify the topics I am not certain about.
Please @matklad, @edwin0cheng review carefully, I even left some mentions of your names in todos to put your attention where you most probably can give comments.
In order to simplify the review, I separated the codegen (i.e. changes in `ast/generated/nodes.rs`) from `ast_src` changes (they in fact just duplicate one another) into two commits.
Also, I had to hack a little bit to let the docs be generated as doc comments and not as doc attributes because it's easier to read them this way and IIRC we don't support hints for `#[doc = ""]` attributes for now...
Closes#3682
Co-authored-by: veetaha <veetaha2@gmail.com>
This reverts commit 7a49165f5d.
MacroStmts ast node is not used by itself, but it pertains
to SyntaxNodeKind MACRO_STMTS that is used by ra_paser, so
even tho the node itself is not used, it is better to keep it
with a FIXME to actually add a doc comment when it becomes useful.
4246: Validate uses of self and super r=matklad a=djrenren
This change follows on the validation of the `crate` keyword in paths. It verifies the following things:
`super`:
- May only be preceded by other `super` segments
- If in a `UseItem` then all semantically preceding paths also consist only of `super`
`self`
- May only be the start of a path
Just a note, a couple times while working on this I found myself really wanting a Visitor of some sort so that I could traverse descendants while skipping sub-trees that are unimportant. Iterators don't really work for this, so as you can see I reached for recursion. Considering paths are generally small a fancy debounced visitor probably isn't important but figured I'd say something in case we had something like this lying around and I wasn't using it.
Co-authored-by: John Renner <john@jrenner.net>
4178: Validate the location of `crate` in paths r=matklad a=djrenren
**This solution does not fully handle `use` statements. See below**
This pull requests implements simple validation of usages of the `crate` keyword in `Path`s. Specifically it validates that:
- If a `PathSegment` is starts with the `crate` keyword, it is also the first segment of the `Path`
- All other usages of `crate` in `Path`s are considered errors.
This aligns with `rustc`'s rules. Unlike rustc this implementation does not issue a special error message in the case of `::crate` but it does catch the error.
Furthermore, this change does not cover all error cases. Specifically the following is not caught:
```rust
use foo::{crate}
```
This is because this check is context sensitive. From an AST perspective, `crate` is the root of the `Path`. Only by inspecting the full `UseItem` do we see that it is not in fact the root. This problem becomes worse because `UseTree`s are allowed to be arbitrarily nested:
```rust
use {crate, {{crate, foo::{crate}}}
```
So this is a hard problem to solve without essentially a breadth-first search. In a traditional compiler, I'd say this error is most easily found during the AST -> HIR conversion pass but within rust-analyzer I'm not sure where it belongs.
Under the implementation in this PR, such errors are ignored so we're *more correct* just not *entirely correct*.
Co-authored-by: John Renner <john@jrenner.net>
