language.rs

  1use anyhow::{anyhow, Context, Result};
  2use async_compression::futures::bufread::GzipDecoder;
  3use client::http::{self, HttpClient, Method};
  4use futures::{future::BoxFuture, FutureExt, StreamExt};
  5use gpui::Task;
  6pub use language::*;
  7use lazy_static::lazy_static;
  8use regex::Regex;
  9use rust_embed::RustEmbed;
 10use serde::Deserialize;
 11use serde_json::json;
 12use smol::fs::{self, File};
 13use std::{borrow::Cow, env::consts, path::PathBuf, str, sync::Arc};
 14use util::{ResultExt, TryFutureExt};
 15
 16#[derive(RustEmbed)]
 17#[folder = "languages"]
 18struct LanguageDir;
 19
 20struct RustLspAdapter;
 21struct CLspAdapter;
 22struct JsonLspAdapter;
 23
 24#[derive(Deserialize)]
 25struct GithubRelease {
 26    name: String,
 27    assets: Vec<GithubReleaseAsset>,
 28}
 29
 30#[derive(Deserialize)]
 31struct GithubReleaseAsset {
 32    name: String,
 33    browser_download_url: http::Url,
 34}
 35
 36impl LspAdapter for RustLspAdapter {
 37    fn name(&self) -> &'static str {
 38        "rust-analyzer"
 39    }
 40
 41    fn fetch_latest_server_version(
 42        &self,
 43        http: Arc<dyn HttpClient>,
 44    ) -> BoxFuture<'static, Result<LspBinaryVersion>> {
 45        async move {
 46            let release = http
 47            .send(
 48                surf::RequestBuilder::new(
 49                    Method::Get,
 50                    http::Url::parse(
 51                        "https://api.github.com/repos/rust-analyzer/rust-analyzer/releases/latest",
 52                    )
 53                    .unwrap(),
 54                )
 55                .middleware(surf::middleware::Redirect::default())
 56                .build(),
 57            )
 58            .await
 59            .map_err(|err| anyhow!("error fetching latest release: {}", err))?
 60            .body_json::<GithubRelease>()
 61            .await
 62            .map_err(|err| anyhow!("error parsing latest release: {}", err))?;
 63            let asset_name = format!("rust-analyzer-{}-apple-darwin.gz", consts::ARCH);
 64            let asset = release
 65                .assets
 66                .iter()
 67                .find(|asset| asset.name == asset_name)
 68                .ok_or_else(|| anyhow!("no release found matching {:?}", asset_name))?;
 69            Ok(LspBinaryVersion {
 70                name: release.name,
 71                url: Some(asset.browser_download_url.clone()),
 72            })
 73        }
 74        .boxed()
 75    }
 76
 77    fn fetch_server_binary(
 78        &self,
 79        version: LspBinaryVersion,
 80        http: Arc<dyn HttpClient>,
 81        container_dir: PathBuf,
 82    ) -> BoxFuture<'static, Result<PathBuf>> {
 83        async move {
 84            let destination_path = container_dir.join(format!("rust-analyzer-{}", version.name));
 85
 86            if fs::metadata(&destination_path).await.is_err() {
 87                let response = http
 88                    .send(
 89                        surf::RequestBuilder::new(Method::Get, version.url.unwrap())
 90                            .middleware(surf::middleware::Redirect::default())
 91                            .build(),
 92                    )
 93                    .await
 94                    .map_err(|err| anyhow!("error downloading release: {}", err))?;
 95                let decompressed_bytes = GzipDecoder::new(response);
 96                let mut file = File::create(&destination_path).await?;
 97                futures::io::copy(decompressed_bytes, &mut file).await?;
 98                fs::set_permissions(
 99                    &destination_path,
100                    <fs::Permissions as fs::unix::PermissionsExt>::from_mode(0o755),
101                )
102                .await?;
103
104                if let Some(mut entries) = fs::read_dir(&container_dir).await.log_err() {
105                    while let Some(entry) = entries.next().await {
106                        if let Some(entry) = entry.log_err() {
107                            let entry_path = entry.path();
108                            if entry_path.as_path() != destination_path {
109                                fs::remove_file(&entry_path).await.log_err();
110                            }
111                        }
112                    }
113                }
114            }
115
116            Ok(destination_path)
117        }
118        .boxed()
119    }
120
121    fn cached_server_binary(&self, container_dir: PathBuf) -> BoxFuture<'static, Option<PathBuf>> {
122        async move {
123            let mut last = None;
124            let mut entries = fs::read_dir(&container_dir).await?;
125            while let Some(entry) = entries.next().await {
126                last = Some(entry?.path());
127            }
128            last.ok_or_else(|| anyhow!("no cached binary"))
129        }
130        .log_err()
131        .boxed()
132    }
133
134    fn process_diagnostics(&self, params: &mut lsp::PublishDiagnosticsParams) {
135        lazy_static! {
136            static ref REGEX: Regex = Regex::new("(?m)`([^`]+)\n`$").unwrap();
137        }
138
139        for diagnostic in &mut params.diagnostics {
140            for message in diagnostic
141                .related_information
142                .iter_mut()
143                .flatten()
144                .map(|info| &mut info.message)
145                .chain([&mut diagnostic.message])
146            {
147                if let Cow::Owned(sanitized) = REGEX.replace_all(message, "`$1`") {
148                    *message = sanitized;
149                }
150            }
151        }
152    }
153
154    fn label_for_completion(
155        &self,
156        completion: &lsp::CompletionItem,
157        language: &Language,
158    ) -> Option<CodeLabel> {
159        match completion.kind {
160            Some(lsp::CompletionItemKind::FIELD) if completion.detail.is_some() => {
161                let detail = completion.detail.as_ref().unwrap();
162                let name = &completion.label;
163                let text = format!("{}: {}", name, detail);
164                let source = Rope::from(format!("struct S {{ {} }}", text).as_str());
165                let runs = language.highlight_text(&source, 11..11 + text.len());
166                return Some(CodeLabel {
167                    text,
168                    runs,
169                    filter_range: 0..name.len(),
170                });
171            }
172            Some(lsp::CompletionItemKind::CONSTANT | lsp::CompletionItemKind::VARIABLE)
173                if completion.detail.is_some() =>
174            {
175                let detail = completion.detail.as_ref().unwrap();
176                let name = &completion.label;
177                let text = format!("{}: {}", name, detail);
178                let source = Rope::from(format!("let {} = ();", text).as_str());
179                let runs = language.highlight_text(&source, 4..4 + text.len());
180                return Some(CodeLabel {
181                    text,
182                    runs,
183                    filter_range: 0..name.len(),
184                });
185            }
186            Some(lsp::CompletionItemKind::FUNCTION | lsp::CompletionItemKind::METHOD)
187                if completion.detail.is_some() =>
188            {
189                lazy_static! {
190                    static ref REGEX: Regex = Regex::new("\\(…?\\)").unwrap();
191                }
192
193                let detail = completion.detail.as_ref().unwrap();
194                if detail.starts_with("fn(") {
195                    let text = REGEX.replace(&completion.label, &detail[2..]).to_string();
196                    let source = Rope::from(format!("fn {} {{}}", text).as_str());
197                    let runs = language.highlight_text(&source, 3..3 + text.len());
198                    return Some(CodeLabel {
199                        filter_range: 0..completion.label.find('(').unwrap_or(text.len()),
200                        text,
201                        runs,
202                    });
203                }
204            }
205            Some(kind) => {
206                let highlight_name = match kind {
207                    lsp::CompletionItemKind::STRUCT
208                    | lsp::CompletionItemKind::INTERFACE
209                    | lsp::CompletionItemKind::ENUM => Some("type"),
210                    lsp::CompletionItemKind::ENUM_MEMBER => Some("variant"),
211                    lsp::CompletionItemKind::KEYWORD => Some("keyword"),
212                    lsp::CompletionItemKind::VALUE | lsp::CompletionItemKind::CONSTANT => {
213                        Some("constant")
214                    }
215                    _ => None,
216                };
217                let highlight_id = language.grammar()?.highlight_id_for_name(highlight_name?)?;
218                let mut label = CodeLabel::plain(completion.label.clone(), None);
219                label.runs.push((
220                    0..label.text.rfind('(').unwrap_or(label.text.len()),
221                    highlight_id,
222                ));
223                return Some(label);
224            }
225            _ => {}
226        }
227        None
228    }
229
230    fn label_for_symbol(
231        &self,
232        name: &str,
233        kind: lsp::SymbolKind,
234        language: &Language,
235    ) -> Option<CodeLabel> {
236        let (text, filter_range, display_range) = match kind {
237            lsp::SymbolKind::METHOD | lsp::SymbolKind::FUNCTION => {
238                let text = format!("fn {} () {{}}", name);
239                let filter_range = 3..3 + name.len();
240                let display_range = 0..filter_range.end;
241                (text, filter_range, display_range)
242            }
243            lsp::SymbolKind::STRUCT => {
244                let text = format!("struct {} {{}}", name);
245                let filter_range = 7..7 + name.len();
246                let display_range = 0..filter_range.end;
247                (text, filter_range, display_range)
248            }
249            lsp::SymbolKind::ENUM => {
250                let text = format!("enum {} {{}}", name);
251                let filter_range = 5..5 + name.len();
252                let display_range = 0..filter_range.end;
253                (text, filter_range, display_range)
254            }
255            lsp::SymbolKind::INTERFACE => {
256                let text = format!("trait {} {{}}", name);
257                let filter_range = 6..6 + name.len();
258                let display_range = 0..filter_range.end;
259                (text, filter_range, display_range)
260            }
261            lsp::SymbolKind::CONSTANT => {
262                let text = format!("const {}: () = ();", name);
263                let filter_range = 6..6 + name.len();
264                let display_range = 0..filter_range.end;
265                (text, filter_range, display_range)
266            }
267            lsp::SymbolKind::MODULE => {
268                let text = format!("mod {} {{}}", name);
269                let filter_range = 4..4 + name.len();
270                let display_range = 0..filter_range.end;
271                (text, filter_range, display_range)
272            }
273            lsp::SymbolKind::TYPE_PARAMETER => {
274                let text = format!("type {} {{}}", name);
275                let filter_range = 5..5 + name.len();
276                let display_range = 0..filter_range.end;
277                (text, filter_range, display_range)
278            }
279            _ => return None,
280        };
281
282        Some(CodeLabel {
283            runs: language.highlight_text(&text.as_str().into(), display_range.clone()),
284            text: text[display_range].to_string(),
285            filter_range,
286        })
287    }
288}
289
290impl LspAdapter for CLspAdapter {
291    fn name(&self) -> &'static str {
292        "clangd"
293    }
294
295    fn fetch_latest_server_version(
296        &self,
297        http: Arc<dyn HttpClient>,
298    ) -> BoxFuture<'static, Result<LspBinaryVersion>> {
299        async move {
300            let release = http
301                .send(
302                    surf::RequestBuilder::new(
303                        Method::Get,
304                        http::Url::parse(
305                            "https://api.github.com/repos/clangd/clangd/releases/latest",
306                        )
307                        .unwrap(),
308                    )
309                    .middleware(surf::middleware::Redirect::default())
310                    .build(),
311                )
312                .await
313                .map_err(|err| anyhow!("error fetching latest release: {}", err))?
314                .body_json::<GithubRelease>()
315                .await
316                .map_err(|err| anyhow!("error parsing latest release: {}", err))?;
317            let asset_name = format!("clangd-mac-{}.zip", release.name);
318            let asset = release
319                .assets
320                .iter()
321                .find(|asset| asset.name == asset_name)
322                .ok_or_else(|| anyhow!("no release found matching {:?}", asset_name))?;
323            Ok(LspBinaryVersion {
324                name: release.name,
325                url: Some(asset.browser_download_url.clone()),
326            })
327        }
328        .boxed()
329    }
330
331    fn fetch_server_binary(
332        &self,
333        version: LspBinaryVersion,
334        http: Arc<dyn HttpClient>,
335        container_dir: PathBuf,
336    ) -> BoxFuture<'static, Result<PathBuf>> {
337        async move {
338            let zip_path = container_dir.join(format!("clangd_{}.zip", version.name));
339            let version_dir = container_dir.join(format!("clangd_{}", version.name));
340            let binary_path = version_dir.join("bin/clangd");
341
342            if fs::metadata(&binary_path).await.is_err() {
343                let response = http
344                    .send(
345                        surf::RequestBuilder::new(Method::Get, version.url.unwrap())
346                            .middleware(surf::middleware::Redirect::default())
347                            .build(),
348                    )
349                    .await
350                    .map_err(|err| anyhow!("error downloading release: {}", err))?;
351                let mut file = File::create(&zip_path).await?;
352                if !response.status().is_success() {
353                    Err(anyhow!(
354                        "download failed with status {}",
355                        response.status().to_string()
356                    ))?;
357                }
358                futures::io::copy(response, &mut file).await?;
359
360                let unzip_status = smol::process::Command::new("unzip")
361                    .current_dir(&container_dir)
362                    .arg(&zip_path)
363                    .output()
364                    .await?
365                    .status;
366                if !unzip_status.success() {
367                    Err(anyhow!("failed to unzip clangd archive"))?;
368                }
369
370                if let Some(mut entries) = fs::read_dir(&container_dir).await.log_err() {
371                    while let Some(entry) = entries.next().await {
372                        if let Some(entry) = entry.log_err() {
373                            let entry_path = entry.path();
374                            if entry_path.as_path() != version_dir {
375                                fs::remove_dir_all(&entry_path).await.log_err();
376                            }
377                        }
378                    }
379                }
380            }
381
382            Ok(binary_path)
383        }
384        .boxed()
385    }
386
387    fn cached_server_binary(&self, container_dir: PathBuf) -> BoxFuture<'static, Option<PathBuf>> {
388        async move {
389            let mut last_clangd_dir = None;
390            let mut entries = fs::read_dir(&container_dir).await?;
391            while let Some(entry) = entries.next().await {
392                let entry = entry?;
393                if entry.file_type().await?.is_dir() {
394                    last_clangd_dir = Some(entry.path());
395                }
396            }
397            let clangd_dir = last_clangd_dir.ok_or_else(|| anyhow!("no cached binary"))?;
398            let clangd_bin = clangd_dir.join("bin/clangd");
399            if clangd_bin.exists() {
400                Ok(clangd_bin)
401            } else {
402                Err(anyhow!(
403                    "missing clangd binary in directory {:?}",
404                    clangd_dir
405                ))
406            }
407        }
408        .log_err()
409        .boxed()
410    }
411
412    fn process_diagnostics(&self, _: &mut lsp::PublishDiagnosticsParams) {}
413}
414
415impl JsonLspAdapter {
416    const BIN_PATH: &'static str =
417        "node_modules/vscode-json-languageserver/bin/vscode-json-languageserver";
418}
419
420impl LspAdapter for JsonLspAdapter {
421    fn name(&self) -> &'static str {
422        "vscode-json-languageserver"
423    }
424
425    fn server_args(&self) -> &[&str] {
426        &["--stdio"]
427    }
428
429    fn fetch_latest_server_version(
430        &self,
431        _: Arc<dyn HttpClient>,
432    ) -> BoxFuture<'static, Result<LspBinaryVersion>> {
433        async move {
434            #[derive(Deserialize)]
435            struct NpmInfo {
436                versions: Vec<String>,
437            }
438
439            let output = smol::process::Command::new("npm")
440                .args(["info", "vscode-json-languageserver", "--json"])
441                .output()
442                .await?;
443            if !output.status.success() {
444                Err(anyhow!("failed to execute npm info"))?;
445            }
446            let mut info: NpmInfo = serde_json::from_slice(&output.stdout)?;
447
448            Ok(LspBinaryVersion {
449                name: info
450                    .versions
451                    .pop()
452                    .ok_or_else(|| anyhow!("no versions found in npm info"))?,
453                url: Default::default(),
454            })
455        }
456        .boxed()
457    }
458
459    fn fetch_server_binary(
460        &self,
461        version: LspBinaryVersion,
462        _: Arc<dyn HttpClient>,
463        container_dir: PathBuf,
464    ) -> BoxFuture<'static, Result<PathBuf>> {
465        async move {
466            let version_dir = container_dir.join(&version.name);
467            fs::create_dir_all(&version_dir)
468                .await
469                .context("failed to create version directory")?;
470            let binary_path = version_dir.join(Self::BIN_PATH);
471
472            if fs::metadata(&binary_path).await.is_err() {
473                let output = smol::process::Command::new("npm")
474                    .current_dir(&version_dir)
475                    .arg("install")
476                    .arg(format!("vscode-json-languageserver@{}", version.name))
477                    .output()
478                    .await
479                    .context("failed to run npm install")?;
480                if !output.status.success() {
481                    Err(anyhow!("failed to install vscode-json-languageserver"))?;
482                }
483
484                if let Some(mut entries) = fs::read_dir(&container_dir).await.log_err() {
485                    while let Some(entry) = entries.next().await {
486                        if let Some(entry) = entry.log_err() {
487                            let entry_path = entry.path();
488                            if entry_path.as_path() != version_dir {
489                                fs::remove_dir_all(&entry_path).await.log_err();
490                            }
491                        }
492                    }
493                }
494            }
495
496            Ok(binary_path)
497        }
498        .boxed()
499    }
500
501    fn cached_server_binary(&self, container_dir: PathBuf) -> BoxFuture<'static, Option<PathBuf>> {
502        async move {
503            let mut last_version_dir = None;
504            let mut entries = fs::read_dir(&container_dir).await?;
505            while let Some(entry) = entries.next().await {
506                let entry = entry?;
507                if entry.file_type().await?.is_dir() {
508                    last_version_dir = Some(entry.path());
509                }
510            }
511            let last_version_dir = last_version_dir.ok_or_else(|| anyhow!("no cached binary"))?;
512            let bin_path = last_version_dir.join(Self::BIN_PATH);
513            if bin_path.exists() {
514                Ok(bin_path)
515            } else {
516                Err(anyhow!(
517                    "missing executable in directory {:?}",
518                    last_version_dir
519                ))
520            }
521        }
522        .log_err()
523        .boxed()
524    }
525
526    fn process_diagnostics(&self, _: &mut lsp::PublishDiagnosticsParams) {}
527
528    fn initialization_options(&self) -> Option<serde_json::Value> {
529        Some(json!({
530            "provideFormatter": true
531        }))
532    }
533}
534
535pub fn build_language_registry(login_shell_env_loaded: Task<()>) -> LanguageRegistry {
536    let mut languages = LanguageRegistry::new(login_shell_env_loaded);
537    languages.set_language_server_download_dir(
538        dirs::home_dir()
539            .expect("failed to determine home directory")
540            .join(".zed"),
541    );
542    languages.add(Arc::new(c()));
543    languages.add(Arc::new(json()));
544    languages.add(Arc::new(rust()));
545    languages.add(Arc::new(markdown()));
546    languages
547}
548
549fn rust() -> Language {
550    let grammar = tree_sitter_rust::language();
551    let config = toml::from_slice(&LanguageDir::get("rust/config.toml").unwrap().data).unwrap();
552    Language::new(config, Some(grammar))
553        .with_highlights_query(load_query("rust/highlights.scm").as_ref())
554        .unwrap()
555        .with_brackets_query(load_query("rust/brackets.scm").as_ref())
556        .unwrap()
557        .with_indents_query(load_query("rust/indents.scm").as_ref())
558        .unwrap()
559        .with_outline_query(load_query("rust/outline.scm").as_ref())
560        .unwrap()
561        .with_lsp_adapter(RustLspAdapter)
562}
563
564fn c() -> Language {
565    let grammar = tree_sitter_c::language();
566    let config = toml::from_slice(&LanguageDir::get("c/config.toml").unwrap().data).unwrap();
567    Language::new(config, Some(grammar))
568        .with_highlights_query(load_query("c/highlights.scm").as_ref())
569        .unwrap()
570        .with_brackets_query(load_query("c/brackets.scm").as_ref())
571        .unwrap()
572        .with_indents_query(load_query("c/indents.scm").as_ref())
573        .unwrap()
574        .with_outline_query(load_query("c/outline.scm").as_ref())
575        .unwrap()
576        .with_lsp_adapter(CLspAdapter)
577}
578
579fn json() -> Language {
580    let grammar = tree_sitter_json::language();
581    let config = toml::from_slice(&LanguageDir::get("json/config.toml").unwrap().data).unwrap();
582    Language::new(config, Some(grammar))
583        .with_highlights_query(load_query("json/highlights.scm").as_ref())
584        .unwrap()
585        .with_brackets_query(load_query("json/brackets.scm").as_ref())
586        .unwrap()
587        .with_indents_query(load_query("json/indents.scm").as_ref())
588        .unwrap()
589        .with_outline_query(load_query("json/outline.scm").as_ref())
590        .unwrap()
591        .with_lsp_adapter(JsonLspAdapter)
592}
593
594fn markdown() -> Language {
595    let grammar = tree_sitter_markdown::language();
596    let config = toml::from_slice(&LanguageDir::get("markdown/config.toml").unwrap().data).unwrap();
597    Language::new(config, Some(grammar))
598        .with_highlights_query(load_query("markdown/highlights.scm").as_ref())
599        .unwrap()
600}
601
602fn load_query(path: &str) -> Cow<'static, str> {
603    match LanguageDir::get(path).unwrap().data {
604        Cow::Borrowed(s) => Cow::Borrowed(str::from_utf8(s).unwrap()),
605        Cow::Owned(s) => Cow::Owned(String::from_utf8(s).unwrap()),
606    }
607}
608
609#[cfg(test)]
610mod tests {
611    use super::*;
612    use gpui::color::Color;
613    use language::LspAdapter;
614    use theme::SyntaxTheme;
615
616    #[test]
617    fn test_process_rust_diagnostics() {
618        let mut params = lsp::PublishDiagnosticsParams {
619            uri: lsp::Url::from_file_path("/a").unwrap(),
620            version: None,
621            diagnostics: vec![
622                // no newlines
623                lsp::Diagnostic {
624                    message: "use of moved value `a`".to_string(),
625                    ..Default::default()
626                },
627                // newline at the end of a code span
628                lsp::Diagnostic {
629                    message: "consider importing this struct: `use b::c;\n`".to_string(),
630                    ..Default::default()
631                },
632                // code span starting right after a newline
633                lsp::Diagnostic {
634                    message: "cannot borrow `self.d` as mutable\n`self` is a `&` reference"
635                        .to_string(),
636                    ..Default::default()
637                },
638            ],
639        };
640        RustLspAdapter.process_diagnostics(&mut params);
641
642        assert_eq!(params.diagnostics[0].message, "use of moved value `a`");
643
644        // remove trailing newline from code span
645        assert_eq!(
646            params.diagnostics[1].message,
647            "consider importing this struct: `use b::c;`"
648        );
649
650        // do not remove newline before the start of code span
651        assert_eq!(
652            params.diagnostics[2].message,
653            "cannot borrow `self.d` as mutable\n`self` is a `&` reference"
654        );
655    }
656
657    #[test]
658    fn test_rust_label_for_completion() {
659        let language = rust();
660        let grammar = language.grammar().unwrap();
661        let theme = SyntaxTheme::new(vec![
662            ("type".into(), Color::green().into()),
663            ("keyword".into(), Color::blue().into()),
664            ("function".into(), Color::red().into()),
665            ("property".into(), Color::white().into()),
666        ]);
667
668        language.set_theme(&theme);
669
670        let highlight_function = grammar.highlight_id_for_name("function").unwrap();
671        let highlight_type = grammar.highlight_id_for_name("type").unwrap();
672        let highlight_keyword = grammar.highlight_id_for_name("keyword").unwrap();
673        let highlight_field = grammar.highlight_id_for_name("property").unwrap();
674
675        assert_eq!(
676            language.label_for_completion(&lsp::CompletionItem {
677                kind: Some(lsp::CompletionItemKind::FUNCTION),
678                label: "hello(…)".to_string(),
679                detail: Some("fn(&mut Option<T>) -> Vec<T>".to_string()),
680                ..Default::default()
681            }),
682            Some(CodeLabel {
683                text: "hello(&mut Option<T>) -> Vec<T>".to_string(),
684                filter_range: 0..5,
685                runs: vec![
686                    (0..5, highlight_function),
687                    (7..10, highlight_keyword),
688                    (11..17, highlight_type),
689                    (18..19, highlight_type),
690                    (25..28, highlight_type),
691                    (29..30, highlight_type),
692                ],
693            })
694        );
695
696        assert_eq!(
697            language.label_for_completion(&lsp::CompletionItem {
698                kind: Some(lsp::CompletionItemKind::FIELD),
699                label: "len".to_string(),
700                detail: Some("usize".to_string()),
701                ..Default::default()
702            }),
703            Some(CodeLabel {
704                text: "len: usize".to_string(),
705                filter_range: 0..3,
706                runs: vec![(0..3, highlight_field), (5..10, highlight_type),],
707            })
708        );
709
710        assert_eq!(
711            language.label_for_completion(&lsp::CompletionItem {
712                kind: Some(lsp::CompletionItemKind::FUNCTION),
713                label: "hello(…)".to_string(),
714                detail: Some("fn(&mut Option<T>) -> Vec<T>".to_string()),
715                ..Default::default()
716            }),
717            Some(CodeLabel {
718                text: "hello(&mut Option<T>) -> Vec<T>".to_string(),
719                filter_range: 0..5,
720                runs: vec![
721                    (0..5, highlight_function),
722                    (7..10, highlight_keyword),
723                    (11..17, highlight_type),
724                    (18..19, highlight_type),
725                    (25..28, highlight_type),
726                    (29..30, highlight_type),
727                ],
728            })
729        );
730    }
731
732    #[test]
733    fn test_rust_label_for_symbol() {
734        let language = rust();
735        let grammar = language.grammar().unwrap();
736        let theme = SyntaxTheme::new(vec![
737            ("type".into(), Color::green().into()),
738            ("keyword".into(), Color::blue().into()),
739            ("function".into(), Color::red().into()),
740            ("property".into(), Color::white().into()),
741        ]);
742
743        language.set_theme(&theme);
744
745        let highlight_function = grammar.highlight_id_for_name("function").unwrap();
746        let highlight_type = grammar.highlight_id_for_name("type").unwrap();
747        let highlight_keyword = grammar.highlight_id_for_name("keyword").unwrap();
748
749        assert_eq!(
750            language.label_for_symbol("hello", lsp::SymbolKind::FUNCTION),
751            Some(CodeLabel {
752                text: "fn hello".to_string(),
753                filter_range: 3..8,
754                runs: vec![(0..2, highlight_keyword), (3..8, highlight_function)],
755            })
756        );
757
758        assert_eq!(
759            language.label_for_symbol("World", lsp::SymbolKind::TYPE_PARAMETER),
760            Some(CodeLabel {
761                text: "type World".to_string(),
762                filter_range: 5..10,
763                runs: vec![(0..4, highlight_keyword), (5..10, highlight_type)],
764            })
765        );
766    }
767}