7891: Improve handling of rustc_private r=matklad a=DJMcNab
This PR changes how `rust-analyzer` handles `rustc_private`. In particular, packages now must opt-in to using `rustc_private` in `Cargo.toml`, by adding:
```toml
[package.metadata.rust-analyzer]
rustc_private=true
```
This means that depending on crates which also use `rustc_private` will be significantly improved, since their dependencies on the `rustc_private` crates will be resolved properly.
A similar approach could be used in #6714 to allow annotating that your package uses the `test` crate, although I have not yet handled that in this PR.
Additionally, we now only index the crates which are transitive dependencies of `rustc_driver` in the `rustcSource` directory. This should not cause any change in behaviour when using `rustcSource: "discover"`, as the source used then will only be a partial clone. However, if `rustcSource` pointing at a local checkout of rustc, this should significantly improve the memory usage and lower indexing time. This is because we avoids indexing all crates in `src/tools/`, which includes `rust-analyzer` itself.
Furthermore, we also prefer named dependencies over dependencies from `rustcSource`. This ensures that feature resolution for crates which are depended on by both `rustc` and your crate uses the correct set for analysing your crate.
See also [introductory zulip stream](https://rust-lang.zulipchat.com/#narrow/stream/185405-t-compiler.2Fwg-rls-2.2E0/topic/Fixed.20crate.20graphs.20and.20optional.20builtin.20crates/near/229086673)
I have tested this in [priroda](https://github.com/oli-obk/priroda/), and it provides a significant improvement to the development experience (once I give `miri` the required data in `Cargo.toml`)
Todo:
- [ ] Documentation
This is ready to review, and I will add documentation if this would be accepted (or if I get time to do so anyway)
Co-authored-by: Daniel McNab <36049421+DJMcNab@users.noreply.github.com>
`vim-lsp` is another popular LSP client for Vim. And, as there is no
`rust-analyzer` specific UI, it is non-trivial to figure out how the
initial configuration is performed.
Rather than eagerly converting JSON, we losslessly keep it as is, and
change the shape of user-submitted data at the last moment.
This also allows us to remove a bunch of wrong Defaults
Use two consecutive newlines (`\n\n`) to actually continue text on a
new line.
Use proper markup to reference related settings.
Consistently format references to files, editor commands, command line
arguments, files, etc. as `code`.
Fix typos, add missing full-stops, add missing default values.
derive(Clone, Copy) reads better than derive(Copy, Clone).
However, we preserve the reverse ordering in the lookup text for
sorting purposes. That way, it's convenient to type just `Ord` to
derive everything.
