extension_api.rs

  1//! The Zed Rust Extension API allows you write extensions for [Zed](https://zed.dev/) in Rust.
  2
  3pub mod http_client;
  4pub mod settings;
  5
  6use core::fmt;
  7
  8use wit::*;
  9
 10pub use serde_json;
 11
 12// WIT re-exports.
 13//
 14// We explicitly enumerate the symbols we want to re-export, as there are some
 15// that we may want to shadow to provide a cleaner Rust API.
 16pub use wit::{
 17    download_file, make_file_executable,
 18    zed::extension::github::{
 19        github_release_by_tag_name, latest_github_release, GithubRelease, GithubReleaseAsset,
 20        GithubReleaseOptions,
 21    },
 22    zed::extension::nodejs::{
 23        node_binary_path, npm_install_package, npm_package_installed_version,
 24        npm_package_latest_version,
 25    },
 26    zed::extension::platform::{current_platform, Architecture, Os},
 27    zed::extension::slash_command::{
 28        SlashCommand, SlashCommandArgumentCompletion, SlashCommandOutput, SlashCommandOutputSection,
 29    },
 30    CodeLabel, CodeLabelSpan, CodeLabelSpanLiteral, Command, DownloadedFileType, EnvVars,
 31    KeyValueStore, LanguageServerInstallationStatus, Range, Worktree,
 32};
 33
 34// Undocumented WIT re-exports.
 35//
 36// These are symbols that need to be public for the purposes of implementing
 37// the extension host, but aren't relevant to extension authors.
 38#[doc(hidden)]
 39pub use wit::Guest;
 40
 41/// Constructs for interacting with language servers over the
 42/// Language Server Protocol (LSP).
 43pub mod lsp {
 44    pub use crate::wit::zed::extension::lsp::{
 45        Completion, CompletionKind, InsertTextFormat, Symbol, SymbolKind,
 46    };
 47}
 48
 49/// A result returned from a Zed extension.
 50pub type Result<T, E = String> = core::result::Result<T, E>;
 51
 52/// Updates the installation status for the given language server.
 53pub fn set_language_server_installation_status(
 54    language_server_id: &LanguageServerId,
 55    status: &LanguageServerInstallationStatus,
 56) {
 57    wit::set_language_server_installation_status(&language_server_id.0, status)
 58}
 59
 60/// A Zed extension.
 61pub trait Extension: Send + Sync {
 62    /// Returns a new instance of the extension.
 63    fn new() -> Self
 64    where
 65        Self: Sized;
 66
 67    /// Returns the command used to start the language server for the specified
 68    /// language.
 69    fn language_server_command(
 70        &mut self,
 71        _language_server_id: &LanguageServerId,
 72        _worktree: &Worktree,
 73    ) -> Result<Command> {
 74        Err("`language_server_command` not implemented".to_string())
 75    }
 76
 77    /// Returns the initialization options to pass to the specified language server.
 78    fn language_server_initialization_options(
 79        &mut self,
 80        _language_server_id: &LanguageServerId,
 81        _worktree: &Worktree,
 82    ) -> Result<Option<serde_json::Value>> {
 83        Ok(None)
 84    }
 85
 86    /// Returns the workspace configuration options to pass to the language server.
 87    fn language_server_workspace_configuration(
 88        &mut self,
 89        _language_server_id: &LanguageServerId,
 90        _worktree: &Worktree,
 91    ) -> Result<Option<serde_json::Value>> {
 92        Ok(None)
 93    }
 94
 95    /// Returns the label for the given completion.
 96    fn label_for_completion(
 97        &self,
 98        _language_server_id: &LanguageServerId,
 99        _completion: Completion,
100    ) -> Option<CodeLabel> {
101        None
102    }
103
104    /// Returns the label for the given symbol.
105    fn label_for_symbol(
106        &self,
107        _language_server_id: &LanguageServerId,
108        _symbol: Symbol,
109    ) -> Option<CodeLabel> {
110        None
111    }
112
113    /// Returns the completions that should be shown when completing the provided slash command with the given query.
114    fn complete_slash_command_argument(
115        &self,
116        _command: SlashCommand,
117        _args: Vec<String>,
118    ) -> Result<Vec<SlashCommandArgumentCompletion>, String> {
119        Ok(Vec::new())
120    }
121
122    /// Returns the output from running the provided slash command.
123    fn run_slash_command(
124        &self,
125        _command: SlashCommand,
126        _args: Vec<String>,
127        _worktree: Option<&Worktree>,
128    ) -> Result<SlashCommandOutput, String> {
129        Err("`run_slash_command` not implemented".to_string())
130    }
131
132    /// Returns the command used to start a context server.
133    fn context_server_command(&mut self, _context_server_id: &ContextServerId) -> Result<Command> {
134        Err("`context_server_command` not implemented".to_string())
135    }
136
137    /// Returns a list of package names as suggestions to be included in the
138    /// search results of the `/docs` slash command.
139    ///
140    /// This can be used to provide completions for known packages (e.g., from the
141    /// local project or a registry) before a package has been indexed.
142    fn suggest_docs_packages(&self, _provider: String) -> Result<Vec<String>, String> {
143        Ok(Vec::new())
144    }
145
146    /// Indexes the docs for the specified package.
147    fn index_docs(
148        &self,
149        _provider: String,
150        _package: String,
151        _database: &KeyValueStore,
152    ) -> Result<(), String> {
153        Err("`index_docs` not implemented".to_string())
154    }
155}
156
157/// Registers the provided type as a Zed extension.
158///
159/// The type must implement the [`Extension`] trait.
160#[macro_export]
161macro_rules! register_extension {
162    ($extension_type:ty) => {
163        #[export_name = "init-extension"]
164        pub extern "C" fn __init_extension() {
165            std::env::set_current_dir(std::env::var("PWD").unwrap()).unwrap();
166            zed_extension_api::register_extension(|| {
167                Box::new(<$extension_type as zed_extension_api::Extension>::new())
168            });
169        }
170    };
171}
172
173#[doc(hidden)]
174pub fn register_extension(build_extension: fn() -> Box<dyn Extension>) {
175    unsafe { EXTENSION = Some((build_extension)()) }
176}
177
178fn extension() -> &'static mut dyn Extension {
179    unsafe { EXTENSION.as_deref_mut().unwrap() }
180}
181
182static mut EXTENSION: Option<Box<dyn Extension>> = None;
183
184#[cfg(target_arch = "wasm32")]
185#[link_section = "zed:api-version"]
186#[doc(hidden)]
187pub static ZED_API_VERSION: [u8; 6] = *include_bytes!(concat!(env!("OUT_DIR"), "/version_bytes"));
188
189mod wit {
190    #![allow(clippy::too_many_arguments, clippy::missing_safety_doc)]
191
192    wit_bindgen::generate!({
193        skip: ["init-extension"],
194        path: "./wit/since_v0.2.0",
195    });
196}
197
198wit::export!(Component);
199
200struct Component;
201
202impl wit::Guest for Component {
203    fn language_server_command(
204        language_server_id: String,
205        worktree: &wit::Worktree,
206    ) -> Result<wit::Command> {
207        let language_server_id = LanguageServerId(language_server_id);
208        extension().language_server_command(&language_server_id, worktree)
209    }
210
211    fn language_server_initialization_options(
212        language_server_id: String,
213        worktree: &Worktree,
214    ) -> Result<Option<String>, String> {
215        let language_server_id = LanguageServerId(language_server_id);
216        Ok(extension()
217            .language_server_initialization_options(&language_server_id, worktree)?
218            .and_then(|value| serde_json::to_string(&value).ok()))
219    }
220
221    fn language_server_workspace_configuration(
222        language_server_id: String,
223        worktree: &Worktree,
224    ) -> Result<Option<String>, String> {
225        let language_server_id = LanguageServerId(language_server_id);
226        Ok(extension()
227            .language_server_workspace_configuration(&language_server_id, worktree)?
228            .and_then(|value| serde_json::to_string(&value).ok()))
229    }
230
231    fn labels_for_completions(
232        language_server_id: String,
233        completions: Vec<Completion>,
234    ) -> Result<Vec<Option<CodeLabel>>, String> {
235        let language_server_id = LanguageServerId(language_server_id);
236        let mut labels = Vec::new();
237        for (ix, completion) in completions.into_iter().enumerate() {
238            let label = extension().label_for_completion(&language_server_id, completion);
239            if let Some(label) = label {
240                labels.resize(ix + 1, None);
241                *labels.last_mut().unwrap() = Some(label);
242            }
243        }
244        Ok(labels)
245    }
246
247    fn labels_for_symbols(
248        language_server_id: String,
249        symbols: Vec<Symbol>,
250    ) -> Result<Vec<Option<CodeLabel>>, String> {
251        let language_server_id = LanguageServerId(language_server_id);
252        let mut labels = Vec::new();
253        for (ix, symbol) in symbols.into_iter().enumerate() {
254            let label = extension().label_for_symbol(&language_server_id, symbol);
255            if let Some(label) = label {
256                labels.resize(ix + 1, None);
257                *labels.last_mut().unwrap() = Some(label);
258            }
259        }
260        Ok(labels)
261    }
262
263    fn complete_slash_command_argument(
264        command: SlashCommand,
265        args: Vec<String>,
266    ) -> Result<Vec<SlashCommandArgumentCompletion>, String> {
267        extension().complete_slash_command_argument(command, args)
268    }
269
270    fn run_slash_command(
271        command: SlashCommand,
272        args: Vec<String>,
273        worktree: Option<&Worktree>,
274    ) -> Result<SlashCommandOutput, String> {
275        extension().run_slash_command(command, args, worktree)
276    }
277
278    fn context_server_command(context_server_id: String) -> Result<wit::Command> {
279        let context_server_id = ContextServerId(context_server_id);
280        extension().context_server_command(&context_server_id)
281    }
282
283    fn suggest_docs_packages(provider: String) -> Result<Vec<String>, String> {
284        extension().suggest_docs_packages(provider)
285    }
286
287    fn index_docs(
288        provider: String,
289        package: String,
290        database: &KeyValueStore,
291    ) -> Result<(), String> {
292        extension().index_docs(provider, package, database)
293    }
294}
295
296/// The ID of a language server.
297#[derive(Debug, PartialEq, Eq, PartialOrd, Ord, Hash, Clone)]
298pub struct LanguageServerId(String);
299
300impl AsRef<str> for LanguageServerId {
301    fn as_ref(&self) -> &str {
302        &self.0
303    }
304}
305
306impl fmt::Display for LanguageServerId {
307    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
308        write!(f, "{}", self.0)
309    }
310}
311
312/// The ID of a context server.
313#[derive(Debug, PartialEq, Eq, PartialOrd, Ord, Hash, Clone)]
314pub struct ContextServerId(String);
315
316impl AsRef<str> for ContextServerId {
317    fn as_ref(&self) -> &str {
318        &self.0
319    }
320}
321
322impl fmt::Display for ContextServerId {
323    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
324        write!(f, "{}", self.0)
325    }
326}
327
328impl CodeLabelSpan {
329    /// Returns a [`CodeLabelSpan::CodeRange`].
330    pub fn code_range(range: impl Into<wit::Range>) -> Self {
331        Self::CodeRange(range.into())
332    }
333
334    /// Returns a [`CodeLabelSpan::Literal`].
335    pub fn literal(text: impl Into<String>, highlight_name: Option<String>) -> Self {
336        Self::Literal(CodeLabelSpanLiteral {
337            text: text.into(),
338            highlight_name,
339        })
340    }
341}
342
343impl From<std::ops::Range<u32>> for wit::Range {
344    fn from(value: std::ops::Range<u32>) -> Self {
345        Self {
346            start: value.start,
347            end: value.end,
348        }
349    }
350}
351
352impl From<std::ops::Range<usize>> for wit::Range {
353    fn from(value: std::ops::Range<usize>) -> Self {
354        Self {
355            start: value.start as u32,
356            end: value.end as u32,
357        }
358    }
359}