Struct LspClient 

pub struct LspClient { /* private fields */ }

An asynchronous client for a single language-server process.

Communication uses JSON-RPC 2.0 messages framed with Content-Length headers on both stdin (requests/notifications we send) and stdout (responses/notifications the server sends).

Implementations

impl LspClient

pub async fn start( command: &str, args: &[String], workspace: &Path, ) -> Result<Self, LspError>

Start a language server process and perform the LSP handshake.

command is the server binary (e.g. rust-analyzer), args are any extra CLI arguments, and workspace is the root directory that will be communicated to the server as rootUri.

pub async fn send_request( &mut self, method: &str, params: Value, ) -> Result<Value, LspError>

Send a JSON-RPC request and wait for the matching response.

Notifications received while waiting for the response are processed and buffered (e.g. diagnostics) rather than returned.

pub async fn send_notification( &mut self, method: &str, params: Value, ) -> Result<(), LspError>

Send a JSON-RPC notification (no response expected).

pub async fn read_message(&mut self) -> Result<Value, LspError>

Read a single Content-Length-framed JSON-RPC message from the server.

pub async fn ensure_document_open( &mut self, file_path: &Path, ) -> Result<String, LspError>

Ensure a file is opened in the language server.

If the file has not yet been opened, the client reads it from disk and sends a textDocument/didOpen notification. Returns the file:// URI for the file.

pub async fn hover( &mut self, file: &Path, line: u32, character: u32, ) -> Result<Option<HoverResult>, LspError>

Perform a textDocument/hover request.

pub async fn definition( &mut self, file: &Path, line: u32, character: u32, ) -> Result<Vec<Location>, LspError>

Perform a textDocument/definition request.

The response may be a single Location or an array of Locations; both forms are handled.

pub async fn references( &mut self, file: &Path, line: u32, character: u32, ) -> Result<Vec<Location>, LspError>

Perform a textDocument/references request.

pub async fn completions( &mut self, file: &Path, line: u32, character: u32, ) -> Result<Vec<CompletionItem>, LspError>

Perform a textDocument/completion request.

Handles both a plain array response and the CompletionList wrapper.

pub fn diagnostics(&self, file: &Path) -> Result<Vec<Diagnostic>, LspError>

Return cached diagnostics for the given file.

Diagnostics are populated asynchronously by the server via textDocument/publishDiagnostics notifications which are captured every time a response is read. This method itself is synchronous because it only reads from the in-memory cache.

pub async fn rename( &mut self, file: &Path, line: u32, character: u32, new_name: &str, ) -> Result<WorkspaceEdit, LspError>

Perform a textDocument/rename request.

pub async fn format(&mut self, file: &Path) -> Result<Vec<TextEdit>, LspError>

Perform a textDocument/formatting request.

pub async fn shutdown(&mut self) -> Result<(), LspError>

Gracefully shut down the language server.

Sends shutdown followed by exit, then waits for the child process to terminate.

pub fn current_id(&self) -> i64

Returns the current request id counter value.

pub fn is_initialized(&self) -> bool

Returns whether the client has been initialized.

pub fn open_documents(&self) -> &HashSet<String>

Returns a reference to the set of currently-opened document URIs.

pub fn cached_diagnostics(&self) -> &HashMap<String, Vec<Diagnostic>>

Returns a reference to the cached diagnostics map.

pub fn root_uri(&self) -> &str

Returns the root URI communicated to the language server.