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        _query: 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        _argument: Option<String>,
127        _worktree: Option<&Worktree>,
128    ) -> Result<SlashCommandOutput, String> {
129        Err("`run_slash_command` not implemented".to_string())
130    }
131
132    fn index_docs(
133        &self,
134        _provider: String,
135        _package: String,
136        _database: &KeyValueStore,
137    ) -> Result<(), String> {
138        Err("`index_docs` not implemented".to_string())
139    }
140}
141
142/// Registers the provided type as a Zed extension.
143///
144/// The type must implement the [`Extension`] trait.
145#[macro_export]
146macro_rules! register_extension {
147    ($extension_type:ty) => {
148        #[export_name = "init-extension"]
149        pub extern "C" fn __init_extension() {
150            std::env::set_current_dir(std::env::var("PWD").unwrap()).unwrap();
151            zed_extension_api::register_extension(|| {
152                Box::new(<$extension_type as zed_extension_api::Extension>::new())
153            });
154        }
155    };
156}
157
158#[doc(hidden)]
159pub fn register_extension(build_extension: fn() -> Box<dyn Extension>) {
160    unsafe { EXTENSION = Some((build_extension)()) }
161}
162
163fn extension() -> &'static mut dyn Extension {
164    unsafe { EXTENSION.as_deref_mut().unwrap() }
165}
166
167static mut EXTENSION: Option<Box<dyn Extension>> = None;
168
169#[cfg(target_arch = "wasm32")]
170#[link_section = "zed:api-version"]
171#[doc(hidden)]
172pub static ZED_API_VERSION: [u8; 6] = *include_bytes!(concat!(env!("OUT_DIR"), "/version_bytes"));
173
174mod wit {
175    #![allow(clippy::too_many_arguments)]
176
177    wit_bindgen::generate!({
178        skip: ["init-extension"],
179        path: "./wit/since_v0.1.0",
180    });
181}
182
183wit::export!(Component);
184
185struct Component;
186
187impl wit::Guest for Component {
188    fn language_server_command(
189        language_server_id: String,
190        worktree: &wit::Worktree,
191    ) -> Result<wit::Command> {
192        let language_server_id = LanguageServerId(language_server_id);
193        extension().language_server_command(&language_server_id, worktree)
194    }
195
196    fn language_server_initialization_options(
197        language_server_id: String,
198        worktree: &Worktree,
199    ) -> Result<Option<String>, String> {
200        let language_server_id = LanguageServerId(language_server_id);
201        Ok(extension()
202            .language_server_initialization_options(&language_server_id, worktree)?
203            .and_then(|value| serde_json::to_string(&value).ok()))
204    }
205
206    fn language_server_workspace_configuration(
207        language_server_id: String,
208        worktree: &Worktree,
209    ) -> Result<Option<String>, String> {
210        let language_server_id = LanguageServerId(language_server_id);
211        Ok(extension()
212            .language_server_workspace_configuration(&language_server_id, worktree)?
213            .and_then(|value| serde_json::to_string(&value).ok()))
214    }
215
216    fn labels_for_completions(
217        language_server_id: String,
218        completions: Vec<Completion>,
219    ) -> Result<Vec<Option<CodeLabel>>, String> {
220        let language_server_id = LanguageServerId(language_server_id);
221        let mut labels = Vec::new();
222        for (ix, completion) in completions.into_iter().enumerate() {
223            let label = extension().label_for_completion(&language_server_id, completion);
224            if let Some(label) = label {
225                labels.resize(ix + 1, None);
226                *labels.last_mut().unwrap() = Some(label);
227            }
228        }
229        Ok(labels)
230    }
231
232    fn labels_for_symbols(
233        language_server_id: String,
234        symbols: Vec<Symbol>,
235    ) -> Result<Vec<Option<CodeLabel>>, String> {
236        let language_server_id = LanguageServerId(language_server_id);
237        let mut labels = Vec::new();
238        for (ix, symbol) in symbols.into_iter().enumerate() {
239            let label = extension().label_for_symbol(&language_server_id, symbol);
240            if let Some(label) = label {
241                labels.resize(ix + 1, None);
242                *labels.last_mut().unwrap() = Some(label);
243            }
244        }
245        Ok(labels)
246    }
247
248    fn complete_slash_command_argument(
249        command: SlashCommand,
250        query: String,
251    ) -> Result<Vec<SlashCommandArgumentCompletion>, String> {
252        extension().complete_slash_command_argument(command, query)
253    }
254
255    fn run_slash_command(
256        command: SlashCommand,
257        argument: Option<String>,
258        worktree: Option<&Worktree>,
259    ) -> Result<SlashCommandOutput, String> {
260        extension().run_slash_command(command, argument, worktree)
261    }
262
263    fn index_docs(
264        provider: String,
265        package: String,
266        database: &KeyValueStore,
267    ) -> Result<(), String> {
268        extension().index_docs(provider, package, database)
269    }
270}
271
272/// The ID of a language server.
273#[derive(Debug, PartialEq, Eq, PartialOrd, Ord, Hash, Clone)]
274pub struct LanguageServerId(String);
275
276impl AsRef<str> for LanguageServerId {
277    fn as_ref(&self) -> &str {
278        &self.0
279    }
280}
281
282impl fmt::Display for LanguageServerId {
283    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
284        write!(f, "{}", self.0)
285    }
286}
287
288impl CodeLabelSpan {
289    /// Returns a [`CodeLabelSpan::CodeRange`].
290    pub fn code_range(range: impl Into<wit::Range>) -> Self {
291        Self::CodeRange(range.into())
292    }
293
294    /// Returns a [`CodeLabelSpan::Literal`].
295    pub fn literal(text: impl Into<String>, highlight_name: Option<String>) -> Self {
296        Self::Literal(CodeLabelSpanLiteral {
297            text: text.into(),
298            highlight_name,
299        })
300    }
301}
302
303impl From<std::ops::Range<u32>> for wit::Range {
304    fn from(value: std::ops::Range<u32>) -> Self {
305        Self {
306            start: value.start,
307            end: value.end,
308        }
309    }
310}
311
312impl From<std::ops::Range<usize>> for wit::Range {
313    fn from(value: std::ops::Range<usize>) -> Self {
314        Self {
315            start: value.start as u32,
316            end: value.end as u32,
317        }
318    }
319}