Rust#
Server#
For more information about the LSP server, check rls.
Installation#
For more instructions on how to install manually, check here.
Debugger: Yes#
Server note#
NOTE: If you are using rustic-mode, you have to change rustic-lsp-server instead of lsp-rust-server, since it also supports eglot as a lightweight alternative to lsp-mode.
-
lsp-rust-serverChoose LSP server (default is rust-analyzer) -
lsp-rust-switch-serverSwitch priorities of lsp servers
RLS#
Customization#
This is an incomplete list of the available options
-
lsp-rust-rls-server-commandchange command to start RLS -
lsp-rust-show-hover-contextturn off hover tooltips
rustfmt#
Code formatting with rustfmt can be configured with:
lsp-rust-rustfmt-path change default path for rustfmt executable
To enable automatic code format on save, add this to your init.el (rust-mode is assumed to be installed):
(add-hook 'before-save-hook (lambda () (when (eq 'rust-mode major-mode)
(lsp-format-buffer))))
rust-analyzer#
Commands#
lsp-rust-analyzer-syntax-tree#
Display syntax tree for current buffer
lsp-rust-analyzer-status#
Display status information for rust-analyzer
lsp-rust-analyzer-join-lines#
Join selected lines into one, smartly fixing up whitespace and trailing commas
before:
after:
inlay-hints#
lsp-rust-analyzer-inlay-hints-mode enables displaying of inlay hints
NOTE: the inlay hints interact badly with the lsp-ui sideline, because it doesn't seem to consider the overlays in its width calculation, which often leads to lines wrapping around.
Macro expansion#
lsp-rust-analyzer-expand-macro expand macro call at point recursively
Use your own function for displaying macro expansion by customizing lsp-rust-analyzer-macro-expansion-method
Formatted and highlighted result with the default function of rustic.
auto-import#
Get a list of possible auto import candidates with lsp-execute-code-action
Open Cargo.toml#
lsp-rust-analyzer-open-cargo-toml opens the Cargo.toml closest to the current file. Calling it with a universal argument will open the Cargo.toml in another window.
Corresponds to the rust-analyzer LSP extension
Find and execute tests related to current position#
lsp-rust-analyzer-related-tests find all tests related to the current position, asks for user completion and executes the selected test in a compilation buffer.
Corresponds to the rust-analyzer LSP extension
In the example below, first you see that
+ On the left, the function check_infer is defined, on the right another file is opened with many test functions, some of which call check_infer. With the cursor on check_infer, call lsp-rust-analyzer-related-tests and select infer_pattern_match_slice with fuzzy matching. The test is executed on the right with compilation major mode
+ Move the cursor to fn ellipsize and attempt to find related tests to no avail. Confirm that the function is indeed untested by using swiper and finding one place in the file, where the function is called
Caveats#
- Rust Analyzer does not support disabling snippets - https://github.com/rust-analyzer/rust-analyzer/issues/2518
extract signature#
This unmerged PR contains an example method that allows modifying the signature that is displayed by eldoc.
TRAMP Example#
The following is an example configuration for using lsp-mode with a remote rust-analyzer server:
(with-eval-after-load "lsp-rust"
(lsp-register-client
(make-lsp-client
:new-connection (lsp-tramp-connection "rust-analyzer")
:remote? t
:major-modes '(rust-mode rustic-mode)
:initialization-options 'lsp-rust-analyzer--make-init-options
:notification-handlers (ht<-alist lsp-rust-notification-handlers)
:action-handlers (ht ("rust-analyzer.runSingle" #'lsp-rust--analyzer-run-single))
:library-folders-fn (lambda (_workspace) lsp-rust-library-directories)
:after-open-fn (lambda ()
(when lsp-rust-analyzer-server-display-inlay-hints
(lsp-rust-analyzer-inlay-hints-mode)))
:ignore-messages nil
:server-id 'rust-analyzer-remote)))
Available configurations#
lsp-rust-all-features#
Type: boolean
Default: nil
Enable all Cargo features.
lsp-rust-all-targets#
Type: boolean
Default: t
Checks the project as if you were running cargo check --all-targets. I.e., check all targets and integration tests too.
lsp-rust-analyzer-call-info-full#
Type: boolean
Default: t
Whether to show function name and docs in parameter hints.
lsp-rust-analyzer-cargo-all-targets#
Type: boolean
Default: t
Cargo watch all targets or not.
lsp-rust-analyzer-cargo-override-command#
Type: lsp-string-vector
Default: []
Advanced option, fully override the command rust-analyzer uses for checking.
The command should include --message=format=json or similar option.
lsp-rust-analyzer-cargo-run-build-scripts#
Type: boolean
Default: t
Whether to run build scripts (build.rs) for more precise code analysis.
lsp-rust-analyzer-cargo-watch-args#
Type: lsp-string-vector
Default: []
Cargo watch args.
lsp-rust-analyzer-cargo-watch-command#
Type: string
Default: check
Cargo watch command.
lsp-rust-analyzer-cargo-watch-enable#
Type: boolean
Default: t
Enable Cargo watch.
lsp-rust-analyzer-completion-add-call-argument-snippets#
Type: boolean
Default: t
Whether to add argument snippets when completing functions.
lsp-rust-analyzer-completion-add-call-parenthesis#
Type: boolean
Default: t
Whether to add parenthesis when completing functions.
lsp-rust-analyzer-completion-postfix-enable#
Type: boolean
Default: t
Whether to show postfix snippets like dbg, if, not, etc.
lsp-rust-analyzer-diagnostics-disabled#
Type: lsp-string-vector
Default: []
List of native rust-analyzer diagnostics to disable.
lsp-rust-analyzer-diagnostics-enable#
Type: boolean
Default: t
Whether to show native rust-analyzer diagnostics.
lsp-rust-analyzer-diagnostics-enable-experimental#
Type: boolean
Default: t
Whether to show native rust-analyzer diagnostics that are still experimental (might have more false positives than usual).
lsp-rust-analyzer-display-chaining-hints#
Type: boolean
Default: nil
Whether to show inlay type hints for method chains.
lsp-rust-analyzer-display-parameter-hints#
Type: boolean
Default: nil
Whether to show function parameter name inlay hints at the call site.
lsp-rust-analyzer-download-url#
Type: string
Default: https://github.com/rust-analyzer/rust-analyzer/releases/latest/download/rust-analyzer-linux
Automatic download url for Rust Analyzer
lsp-rust-analyzer-exclude-globs#
Type: lsp-string-vector
Default: []
Exclude globs
lsp-rust-analyzer-import-merge-behaviour#
Type: (choice (const none) (const full) (const last))
Default: full
The strategy to use when inserting new imports or merging imports. Valid values are: - "none": No merging - "full": Merge all layers of the import trees - "last": Only merge the last layer of the import trees
lsp-rust-analyzer-import-prefix#
Type: (choice (const plain) (const by_self) (const by_crate))
Default: plain
The path structure for newly inserted paths to use.
Valid values are:
- "plain": Insert import paths relative to the
current module, using up to one super prefix if the parent module
contains the requested item.
- "by_self": Prefix all import paths
with self if they dont begin withself,super,crateor a crate
name
- "by_crate": Force import paths to be absolute by always starting
them withcrate` or the crate name they refer to.
lsp-rust-analyzer-inlay-chain-face#
Type: face
Default: ((t :inherit lsp-rust-analyzer-inlay-face))
Face for inlay chaining hints (e.g. inferred chain intermediate types).
lsp-rust-analyzer-inlay-chain-format#
Type: (string :tag String)
Default: : %s
Format string for chain inlays (part of the inlay face).
lsp-rust-analyzer-inlay-chain-space-format#
Type: (string :tag String)
Default: %s
Format string for spacing around chain inlays (not part of the inlay face).
lsp-rust-analyzer-inlay-face#
Type: face
Default: ((t :inherit font-lock-comment-face))
The face to use for the Rust Analyzer inlays.
lsp-rust-analyzer-inlay-param-face#
Type: face
Default: ((t :inherit lsp-rust-analyzer-inlay-face))
Face for inlay parameter hints (e.g. function parameter names at call-site).
lsp-rust-analyzer-inlay-param-format#
Type: (string :tag String)
Default: %s:
Format string for parameter inlays (part of the inlay face).
lsp-rust-analyzer-inlay-param-space-format#
Type: (string :tag String)
Default: %s
Format string for spacing around parameter inlays (not part of the inlay face).
lsp-rust-analyzer-inlay-type-face#
Type: face
Default: ((t :inherit lsp-rust-analyzer-inlay-face))
Face for inlay type hints (e.g. inferred variable types).
lsp-rust-analyzer-inlay-type-format#
Type: (string :tag String)
Default: : %s
Format string for variable inlays (part of the inlay face).
lsp-rust-analyzer-inlay-type-space-format#
Type: (string :tag String)
Default: %s
Format string for spacing around variable inlays (not part of the inlay face).
lsp-rust-analyzer-lru-capacity#
Type: integer
Default: nil
Number of syntax trees rust-analyzer keeps in memory.
lsp-rust-analyzer-macro-expansion-method#
Type: function
Default: lsp-rust-analyzer-macro-expansion-default
Use a different function if you want formatted macro expansion results and syntax highlighting.
lsp-rust-analyzer-max-inlay-hint-length#
Type: integer
Default: nil
Max inlay hint length.
lsp-rust-analyzer-proc-macro-enable#
Type: boolean
Default: nil
Enable Proc macro support; implies lsp-rust-analyzer-cargo-run-build-scripts
lsp-rust-analyzer-rustfmt-extra-args#
Type: lsp-string-vector
Default: []
Additional arguments to rustfmt.
lsp-rust-analyzer-rustfmt-override-command#
Type: lsp-string-vector
Default: []
Advanced option, fully override the command rust-analyzer uses for formatting.
lsp-rust-analyzer-server-command#
Type: (repeat string)
Default: (rust-analyzer)
Command to start rust-analyzer.
lsp-rust-analyzer-server-display-inlay-hints#
Type: boolean
Default: nil
Show inlay hints.
lsp-rust-analyzer-store-path#
Type: file
Default: ~/.emacs.d/.cache/lsp/rust/rust-analyzer
The path to the file in which rust-analyzer will be stored.
lsp-rust-analyzer-use-client-watching#
Type: boolean
Default: t
Use client watching
lsp-rust-build-bin#
Type: (choice (const :tag None nil) (string :tag Binary))
Default: nil
If non-nil, checks the project as if you passed -- bin <build_bin>
argument to cargo.
Mutually exclusive with lsp-rust-build-lib. (Unstable)
lsp-rust-build-command#
Type: (choice (const :tag None nil) (string :tag Command))
Default: nil
EXPERIMENTAL (requires unstable_features)
If set, executes
a given program responsible for rebuilding save-analysis to be
loaded by the RLS. The program given should output a list of
resulting .json files on stdout.
Implies rust.build_on_save:
true.
lsp-rust-build-lib#
Type: boolean
Default: nil
If non-nil, checks the project as if you passed the --lib argument to
cargo.
Mutually exclusive with, and preferred over, lsp-rust-build-bin. (Unstable)
lsp-rust-build-on-save#
Type: boolean
Default: nil
Only index the project when a file is saved and not on change.
lsp-rust-cfg-test#
Type: boolean
Default: nil
If non-nil, checks the project as if you were running cargo test rather
than cargo build.
I.e., compiles (but does not run) test code.
lsp-rust-clear-env-rust-log#
Type: boolean
Default: t
Clear the RUST_LOG environment variable before running rustc or cargo.
lsp-rust-clippy-preference#
Type: (choice (const on) (const opt-in) (const off))
Default: opt-in
Controls eagerness of clippy diagnostics when available.
Valid values are (case-insensitive):
- "off": Disable clippy
lints.
- "opt-in": Clippy lints are shown when crates
specify #![warn(clippy)].
- "on": Clippy lints enabled
for all crates in workspace.
You need to install clippy via
rustup if you haven`t already.
lsp-rust-crate-blacklist#
Type: lsp-string-vector
Default: [cocoa gleam glium idna libc openssl rustc_serialize serde serde_json typenum unicode_normalization unicode_segmentation winapi]
A list of Cargo crates to blacklist.
lsp-rust-features#
Type: lsp-string-vector
Default: []
List of Cargo features to enable.
lsp-rust-full-docs#
Type: boolean
Default: nil
Instructs cargo to enable full documentation extraction during save-analysis while building the crate.
lsp-rust-jobs#
Type: (choice (const :tag Auto nil) (number :tag Jobs))
Default: nil
Number of Cargo jobs to be run in parallel.
lsp-rust-library-directories#
Type: (repeat string)
Default: (~/.cargo/registry/src ~/.rustup/toolchains)
List of directories which will be considered to be libraries.
lsp-rust-no-default-features#
Type: boolean
Default: nil
Do not enable default Cargo features.
lsp-rust-racer-completion#
Type: boolean
Default: t
Enables code completion using racer.
lsp-rust-rls-server-command#
Type: (repeat string)
Default: (rls)
Command to start RLS.
lsp-rust-rustflags#
Type: (choice (const :tag None nil) (string :tag Flags))
Default: nil
Flags added to RUSTFLAGS.
lsp-rust-rustfmt-path#
Type: (choice (const :tag Bundled nil) (string :tag Path))
Default: nil
When specified, RLS will use the Rustfmt pointed at the path instead of the bundled one
lsp-rust-server#
Type: (choice (const :tag rls rls) (const :tag rust-analyzer rust-analyzer))
Default: rust-analyzer
Choose LSP server.
lsp-rust-show-hover-context#
Type: boolean
Default: t
Show additional context in hover tooltips when available. This is often the type local variable declaration.
lsp-rust-show-warnings#
Type: boolean
Default: t
Show warnings.
lsp-rust-sysroot#
Type: (choice (const :tag None nil) (string :tag Sysroot))
Default: nil
If non-nil, use the given path as the sysroot for all rustc invocations instead of trying to detect the sysroot automatically.
lsp-rust-target#
Type: (choice (const :tag None nil) (string :tag Target))
Default: nil
If non-nil, use the given target triple for all rustc invocations.
lsp-rust-target-dir#
Type: (choice (const :tag Default nil) (string :tag Directory))
Default: nil
When specified, it places the generated analysis files at the specified target directory. By default it is placed target/rls directory.
lsp-rust-unstable-features#
Type: boolean
Default: nil
Enable unstable features.
lsp-rust-wait-to-build#
Type: (choice (const :tag Auto nil) (number :tag Time))
Default: nil
Time in milliseconds between receiving a change notification and starting build. If not specified, automatically inferred by the latest build duration.