## Summary
This builds off of the work in
https://github.com/astral-sh/ruff/pull/10652 to implement a command
executor, backwards compatible with the commands from the previous LSP
(`ruff.applyAutofix`, `ruff.applyFormat` and
`ruff.applyOrganizeImports`).
This involved a lot of refactoring and tweaks to the code action
resolution code - the most notable change is that workspace edits are
specified in a slightly different way, using the more general `changes`
field instead of the `document_changes` field (which isn't supported on
all LSP clients). Additionally, the API for synchronous request handlers
has been updated to include access to the `Requester`, which we use to
send a `workspace/applyEdit` request to the client.
## Test Plan
7932e30f-d944-4e35-b828-1d81aa56c087
## Summary
This builds on top of the work in
https://github.com/astral-sh/ruff/pull/10597 to support `Ruff: Organize
imports` as an available source action.
To do this, we have to support `Clone`-ing for linter settings, since we
need to modify them in place to select import-related diagnostics
specifically (`I001` and `I002`).
## Test Plan
04282d01-dfda-4ac5-aa8f-6a92d5f85bfd
## Summary
`ruff server` now has source action `source.fixAll` as an available code
action.
This also fixes https://github.com/astral-sh/ruff/issues/10593 in the
process of revising the code for quick fix code actions.
## Test Plan
f4c07425-e68a-445f-a4ed-949c9197a6be
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## Summary
This PR introduces the `ruff_server` crate and a new `ruff server`
command. `ruff_server` is a re-implementation of
[`ruff-lsp`](https://github.com/astral-sh/ruff-lsp), written entirely in
Rust. It brings significant performance improvements, much tighter
integration with Ruff, a foundation for supporting entirely new language
server features, and more!
This PR is an early version of `ruff_lsp` that we're calling the
**pre-release** version. Anyone is more than welcome to use it and
submit bug reports for any issues they encounter - we'll have some
documentation on how to set it up with a few common editors, and we'll
also provide a pre-release VSCode extension for those interested.
This pre-release version supports:
- **Diagnostics for `.py` files**
- **Quick fixes**
- **Full-file formatting**
- **Range formatting**
- **Multiple workspace folders**
- **Automatic linter/formatter configuration** - taken from any
`pyproject.toml` files in the workspace.
Many thanks to @MichaReiser for his [proof-of-concept
work](https://github.com/astral-sh/ruff/pull/7262), which was important
groundwork for making this PR possible.
## Architectural Decisions
I've made an executive choice to go with `lsp-server` as a base
framework for the LSP, in favor of `tower-lsp`. There were several
reasons for this:
1. I would like to avoid `async` in our implementation. LSPs are mostly
computationally bound rather than I/O bound, and `async` adds a lot of
complexity to the API, while also making harder to reason about
execution order. This leads into the second reason, which is...
2. Any handlers that mutate state should be blocking and run in the
event loop, and the state should be lock-free. This is the approach that
`rust-analyzer` uses (also with the `lsp-server`/`lsp-types` crates as a
framework), and it gives us assurances about data mutation and execution
order. `tower-lsp` doesn't support this, which has caused some
[issues](https://github.com/ebkalderon/tower-lsp/issues/284) around data
races and out-of-order handler execution.
3. In general, I think it makes sense to have tight control over
scheduling and the specifics of our implementation, in exchange for a
slightly higher up-front cost of writing it ourselves. We'll be able to
fine-tune it to our needs and support future LSP features without
depending on an upstream maintainer.
## Test Plan
The pre-release of `ruff_server` will have snapshot tests for common
document editing scenarios. An expanded test suite is on the roadmap for
future version of `ruff_server`.
