elixir_ls.rs

  1use std::fs;
  2
  3use zed::lsp::{Completion, CompletionKind, Symbol, SymbolKind};
  4use zed::settings::LspSettings;
  5use zed::{serde_json, CodeLabel, CodeLabelSpan, LanguageServerId};
  6use zed_extension_api::{self as zed, Result};
  7
  8pub struct ElixirLs {
  9    cached_binary_path: Option<String>,
 10}
 11
 12impl ElixirLs {
 13    pub const LANGUAGE_SERVER_ID: &'static str = "elixir-ls";
 14
 15    pub fn new() -> Self {
 16        Self {
 17            cached_binary_path: None,
 18        }
 19    }
 20
 21    pub fn language_server_binary_path(
 22        &mut self,
 23        language_server_id: &LanguageServerId,
 24        worktree: &zed::Worktree,
 25    ) -> Result<String> {
 26        if let Some(path) = worktree.which("elixir-ls") {
 27            return Ok(path);
 28        }
 29
 30        if let Some(path) = &self.cached_binary_path {
 31            if fs::metadata(path).map_or(false, |stat| stat.is_file()) {
 32                return Ok(path.clone());
 33            }
 34        }
 35
 36        zed::set_language_server_installation_status(
 37            language_server_id,
 38            &zed::LanguageServerInstallationStatus::CheckingForUpdate,
 39        );
 40        let release = zed::latest_github_release(
 41            "elixir-lsp/elixir-ls",
 42            zed::GithubReleaseOptions {
 43                require_assets: true,
 44                pre_release: false,
 45            },
 46        )?;
 47
 48        let asset_name = format!("elixir-ls-{version}.zip", version = release.version,);
 49
 50        let asset = release
 51            .assets
 52            .iter()
 53            .find(|asset| asset.name == asset_name)
 54            .ok_or_else(|| format!("no asset found matching {:?}", asset_name))?;
 55
 56        let (platform, _arch) = zed::current_platform();
 57        let version_dir = format!("elixir-ls-{}", release.version);
 58        let extension = match platform {
 59            zed::Os::Mac | zed::Os::Linux => "sh",
 60            zed::Os::Windows => "bat",
 61        };
 62        let binary_path = format!("{version_dir}/language_server.{extension}");
 63
 64        if !fs::metadata(&binary_path).map_or(false, |stat| stat.is_file()) {
 65            zed::set_language_server_installation_status(
 66                language_server_id,
 67                &zed::LanguageServerInstallationStatus::Downloading,
 68            );
 69
 70            zed::download_file(
 71                &asset.download_url,
 72                &version_dir,
 73                zed::DownloadedFileType::Zip,
 74            )
 75            .map_err(|e| format!("failed to download file: {e}"))?;
 76
 77            zed::make_file_executable(&binary_path)?;
 78            zed::make_file_executable(&format!("{version_dir}/launch.{extension}"))?;
 79            zed::make_file_executable(&format!("{version_dir}/debug_adapter.{extension}"))?;
 80
 81            let entries =
 82                fs::read_dir(".").map_err(|e| format!("failed to list working directory {e}"))?;
 83            for entry in entries {
 84                let entry = entry.map_err(|e| format!("failed to load directory entry {e}"))?;
 85                if entry.file_name().to_str() != Some(&version_dir) {
 86                    fs::remove_dir_all(entry.path()).ok();
 87                }
 88            }
 89        }
 90
 91        self.cached_binary_path = Some(binary_path.clone());
 92        Ok(binary_path)
 93    }
 94
 95    pub fn language_server_workspace_configuration(
 96        &mut self,
 97        worktree: &zed::Worktree,
 98    ) -> Result<Option<serde_json::Value>> {
 99        let settings = LspSettings::for_worktree("elixir-ls", worktree)
100            .ok()
101            .and_then(|lsp_settings| lsp_settings.settings.clone())
102            .unwrap_or_default();
103
104        Ok(Some(serde_json::json!({
105            "elixirLS": settings
106        })))
107    }
108
109    pub fn label_for_completion(&self, completion: Completion) -> Option<CodeLabel> {
110        let name = &completion.label;
111        let detail = completion
112            .detail
113            .filter(|detail| detail != "alias")
114            .map(|detail| format!(": {detail}"))
115            .unwrap_or("".to_string());
116
117        let detail_span = CodeLabelSpan::literal(detail, Some("comment.unused".to_string()));
118
119        match completion.kind? {
120            CompletionKind::Module | CompletionKind::Class | CompletionKind::Struct => {
121                let defmodule = "defmodule ";
122                let alias = completion
123                    .label_details
124                    .and_then(|details| details.description)
125                    .filter(|description| description.starts_with("alias"))
126                    .map(|description| format!(" ({description})"))
127                    .unwrap_or("".to_string());
128
129                let code = format!("{defmodule}{name}{alias}");
130                let name_start = defmodule.len();
131                let name_end = name_start + name.len();
132
133                Some(CodeLabel {
134                    code,
135                    spans: vec![
136                        CodeLabelSpan::code_range(name_start..name_end),
137                        detail_span,
138                        CodeLabelSpan::code_range(name_end..(name_end + alias.len())),
139                    ],
140                    filter_range: (0..name.len()).into(),
141                })
142            }
143            CompletionKind::Interface => Some(CodeLabel {
144                code: name.to_string(),
145                spans: vec![CodeLabelSpan::code_range(0..name.len()), detail_span],
146                filter_range: (0..name.len()).into(),
147            }),
148            CompletionKind::Field => Some(CodeLabel {
149                code: name.to_string(),
150                spans: vec![
151                    CodeLabelSpan::literal(name, Some("function".to_string())),
152                    detail_span,
153                ],
154                filter_range: (0..name.len()).into(),
155            }),
156            CompletionKind::Function | CompletionKind::Constant => {
157                let detail = completion
158                    .label_details
159                    .clone()
160                    .and_then(|details| details.detail)
161                    .unwrap_or("".to_string());
162
163                let description = completion
164                    .label_details
165                    .clone()
166                    .and_then(|details| details.description)
167                    .map(|description| format!(" ({description})"))
168                    .unwrap_or("".to_string());
169
170                let def = "def ";
171                let code = format!("{def}{name}{detail}{description}");
172
173                let name_start = def.len();
174                let name_end = name_start + name.len();
175                let detail_end = name_end + detail.len();
176                let description_end = detail_end + description.len();
177
178                Some(CodeLabel {
179                    code,
180                    spans: vec![
181                        CodeLabelSpan::code_range(name_start..name_end),
182                        CodeLabelSpan::code_range(name_end..detail_end),
183                        CodeLabelSpan::code_range(detail_end..description_end),
184                    ],
185                    filter_range: (0..name.len()).into(),
186                })
187            }
188            CompletionKind::Operator => {
189                let def_a = "def a ";
190                let code = format!("{def_a}{name} b");
191
192                Some(CodeLabel {
193                    code,
194                    spans: vec![CodeLabelSpan::code_range(
195                        def_a.len()..def_a.len() + name.len(),
196                    )],
197                    filter_range: (0..name.len()).into(),
198                })
199            }
200            _ => None,
201        }
202    }
203
204    pub fn label_for_symbol(&self, symbol: Symbol) -> Option<CodeLabel> {
205        let name = &symbol.name;
206
207        let (code, filter_range, display_range) = match symbol.kind {
208            SymbolKind::Module | SymbolKind::Class | SymbolKind::Interface | SymbolKind::Struct => {
209                let defmodule = "defmodule ";
210                let code = format!("{defmodule}{name}");
211                let filter_range = 0..name.len();
212                let display_range = defmodule.len()..defmodule.len() + name.len();
213                (code, filter_range, display_range)
214            }
215            SymbolKind::Function | SymbolKind::Constant => {
216                let def = "def ";
217                let code = format!("{def}{name}");
218                let filter_range = 0..name.len();
219                let display_range = def.len()..def.len() + name.len();
220                (code, filter_range, display_range)
221            }
222            _ => return None,
223        };
224
225        Some(CodeLabel {
226            spans: vec![CodeLabelSpan::code_range(display_range)],
227            filter_range: filter_range.into(),
228            code,
229        })
230    }
231}