feat: nested document symbols

Cargo.lock

@@ -570,6 +570,18 @@ dependencies = [
  "syn 2.0.52",
 ]
 
+[[package]]
+name = "console"
+version = "0.15.8"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "0e1f83fc076bd6dd27517eacdf25fef6c4dfe5f1d7448bafaaf3a26f13b5e4eb"
+dependencies = [
+ "encode_unicode",
+ "lazy_static",
+ "libc",
+ "windows-sys 0.52.0",
+]
+
 [[package]]
 name = "core-foundation"
 version = "0.9.4"
@@ -913,6 +925,12 @@ version = "0.4.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "ef1a6892d9eef45c8fa6b9e0086428a2cca8491aca8f787c534a3d6d0bcb3ced"
 
+[[package]]
+name = "encode_unicode"
+version = "0.3.6"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "a357d28ed41a50f9c765dbfe56cbc04a64e53e5fc58ba79fbc34c10ef3df831f"
+
 [[package]]
 name = "encoding_rs"
 version = "0.8.33"
@@ -1730,6 +1748,19 @@ dependencies = [
  "libc",
 ]
 
+[[package]]
+name = "insta"
+version = "1.36.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "0a7c22c4d34ef4788c351e971c52bfdfe7ea2766f8c5466bc175dd46e52ac22e"
+dependencies = [
+ "console",
+ "lazy_static",
+ "linked-hash-map",
+ "similar",
+ "yaml-rust",
+]
+
 [[package]]
 name = "instant"
 version = "0.1.12"
@@ -2999,6 +3030,12 @@ version = "0.1.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "f27f6278552951f1f2b8cf9da965d10969b2efdea95a6ec47987ab46edfe263a"
 
+[[package]]
+name = "similar"
+version = "2.4.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "32fea41aca09ee824cc9724996433064c89f7777e60762749a4170a14abbfa21"
+
 [[package]]
 name = "simplecss"
 version = "0.2.1"
@@ -3388,9 +3425,11 @@ version = "0.1.0"
 dependencies = [
  "anyhow",
  "comemo",
+ "insta",
  "itertools 0.12.1",
  "lazy_static",
  "log",
+ "once_cell",
  "parking_lot",
  "regex",
  "serde",

crates/tinymist-query/Cargo.toml

@@ -29,10 +29,17 @@ typst-ide.workspace = true
 typst-ts-core = { version = "0.4.2-rc6", default-features = false, features = [
     "flat-vector",
     "vector-bbox",
+    "no-content-hint",
 ] }
 typst-ts-compiler.workspace = true
 
 tower-lsp.workspace = true
 
+[dev-dependencies]
+once_cell.workspace = true
+insta.workspace = true
+serde.workspace = true
+serde_json.workspace = true
+
 # [lints]
 # workspace = true

crates/tinymist-query/src/document_symbol.rs

@@ -1,3 +1,7 @@
+use std::ops::Range;
+
+use typst_ts_core::typst::prelude::{eco_vec, EcoVec};
+
 use crate::prelude::*;
 
 #[derive(Debug, Clone)]
@@ -13,40 +17,146 @@ impl DocumentSymbolRequest {
     ) -> Option<DocumentSymbolResponse> {
         let source = get_suitable_source_in_workspace(world, &self.path).ok()?;
 
-        let uri = Url::from_file_path(self.path).unwrap();
-        let symbols = get_document_symbols(source, uri, position_encoding);
+        let symbols = get_lexical_hierarchy(source.clone(), LexicalScopeGranularity::None);
 
-        symbols.map(DocumentSymbolResponse::Flat)
+        let symbols =
+            symbols.map(|symbols| filter_document_symbols(&symbols, &source, position_encoding));
+        symbols.map(DocumentSymbolResponse::Nested)
     }
 }
 
-#[comemo::memoize]
-pub(crate) fn get_document_symbols(
-    source: Source,
-    uri: Url,
+#[allow(deprecated)]
+fn filter_document_symbols(
+    symbols: &[LexicalHierarchy],
+    source: &Source,
     position_encoding: PositionEncoding,
-) -> Option<Vec<SymbolInformation>> {
-    struct DocumentSymbolWorker {
-        symbols: Vec<SymbolInformation>,
+) -> Vec<DocumentSymbol> {
+    symbols
+        .iter()
+        .map(|e| {
+            let rng =
+                typst_to_lsp::range(e.info.range.clone(), source, position_encoding).raw_range;
+
+            DocumentSymbol {
+                name: e.info.name.clone(),
+                detail: None,
+                kind: match e.info.kind {
+                    LexicalKind::Namespace(..) => SymbolKind::NAMESPACE,
+                    LexicalKind::Variable => SymbolKind::VARIABLE,
+                    LexicalKind::Function => SymbolKind::FUNCTION,
+                    LexicalKind::Constant => SymbolKind::CONSTANT,
+                    LexicalKind::Block => unreachable!(),
+                },
+                tags: None,
+                deprecated: None,
+                range: rng,
+                selection_range: rng,
+                //             .raw_range,
+                children: e
+                    .children
+                    .as_ref()
+                    .map(|ch| filter_document_symbols(ch, source, position_encoding)),
+            }
+        })
+        .collect()
+}
+
+#[derive(Debug, Clone, Hash)]
+pub(crate) enum LexicalKind {
+    Namespace(i16),
+    Variable,
+    Function,
+    Constant,
+    Block,
+}
+
+#[derive(Debug, Clone, Copy, Hash, Default, PartialEq, Eq)]
+pub(crate) enum LexicalScopeGranularity {
+    #[default]
+    None,
+    Block,
+}
+
+#[derive(Debug, Clone, Hash)]
+pub(crate) struct LexicalInfo {
+    pub name: String,
+    pub kind: LexicalKind,
+    pub range: Range<usize>,
+}
+
+#[derive(Debug, Clone, Hash)]
+pub(crate) struct LexicalHierarchy {
+    pub info: LexicalInfo,
+    pub children: Option<comemo::Prehashed<EcoVec<LexicalHierarchy>>>,
+}
+
+pub(crate) fn get_lexical_hierarchy(
+    source: Source,
+    g: LexicalScopeGranularity,
+) -> Option<EcoVec<LexicalHierarchy>> {
+    fn symbreak(sym: LexicalInfo, curr: EcoVec<LexicalHierarchy>) -> LexicalHierarchy {
+        LexicalHierarchy {
+            info: sym,
+            children: if curr.is_empty() {
+                None
+            } else {
+                Some(comemo::Prehashed::new(curr))
+            },
+        }
     }
 
-    impl DocumentSymbolWorker {
-        /// Get all symbols for a node recursively.
-        pub fn get_symbols<'a>(
-            &mut self,
-            node: LinkedNode<'a>,
-            source: &'a Source,
-            uri: &'a Url,
-            position_encoding: PositionEncoding,
-        ) -> anyhow::Result<()> {
-            let own_symbol = get_ident(&node, source, uri, position_encoding)?;
+    #[derive(Default)]
+    struct LexicalHierarchyWorker {
+        g: LexicalScopeGranularity,
+        stack: Vec<(LexicalInfo, EcoVec<LexicalHierarchy>)>,
+    }
 
-            for child in node.children() {
-                self.get_symbols(child, source, uri, position_encoding)?;
-            }
+    impl LexicalHierarchyWorker {
+        fn symbreak(&mut self) {
+            let (symbol, children) = self.stack.pop().unwrap();
+            let current = &mut self.stack.last_mut().unwrap().1;
+            current.push(symbreak(symbol, children));
+        }
+
+        /// Get all symbols for a node recursively.
+        fn get_symbols(&mut self, node: LinkedNode) -> anyhow::Result<()> {
+            let own_symbol = get_ident(&node, self.g)?;
 
             if let Some(symbol) = own_symbol {
-                self.symbols.push(symbol);
+                if let LexicalKind::Namespace(level) = symbol.kind {
+                    'heading_break: while let Some((w, _)) = self.stack.last() {
+                        match w.kind {
+                            LexicalKind::Namespace(l) if l < level => break 'heading_break,
+                            LexicalKind::Block => break 'heading_break,
+                            _ if self.stack.len() <= 1 => break 'heading_break,
+                            _ => {}
+                        }
+
+                        self.symbreak();
+                    }
+                }
+                let is_heading = matches!(symbol.kind, LexicalKind::Namespace(..));
+
+                self.stack.push((symbol, eco_vec![]));
+                let stack_height = self.stack.len();
+
+                for child in node.children() {
+                    self.get_symbols(child)?;
+                }
+
+                if is_heading {
+                    while stack_height < self.stack.len() {
+                        self.symbreak();
+                    }
+                } else {
+                    while stack_height <= self.stack.len() {
+                        self.symbreak();
+                    }
+                }
+            } else {
+                for child in node.children() {
+                    self.get_symbols(child)?;
+                }
             }
 
             Ok(())
@@ -58,29 +168,21 @@ pub(crate) fn get_document_symbols(
     #[allow(deprecated)]
     fn get_ident(
         node: &LinkedNode,
-        source: &Source,
-        uri: &Url,
-        position_encoding: PositionEncoding,
-    ) -> anyhow::Result<Option<SymbolInformation>> {
-        match node.kind() {
+        g: LexicalScopeGranularity,
+    ) -> anyhow::Result<Option<LexicalInfo>> {
+        let (name, kind) = match node.kind() {
             SyntaxKind::Label => {
                 let ast_node = node
                     .cast::<ast::Label>()
                     .ok_or_else(|| anyhow!("cast to ast node failed: {:?}", node))?;
                 let name = ast_node.get().to_string();
-                let symbol = SymbolInformation {
-                    name,
-                    kind: SymbolKind::CONSTANT,
-                    tags: None,
-                    deprecated: None, // do not use, deprecated, use `tags` instead
-                    location: LspLocation {
-                        uri: uri.clone(),
-                        range: typst_to_lsp::range(node.range(), source, position_encoding)
-                            .raw_range,
-                    },
-                    container_name: None,
-                };
-                Ok(Some(symbol))
+
+                (name, LexicalKind::Constant)
+            }
+            SyntaxKind::CodeBlock | SyntaxKind::ContentBlock
+                if LexicalScopeGranularity::None != g =>
+            {
+                (String::new(), LexicalKind::Block)
             }
             SyntaxKind::Ident => {
                 let ast_node = node
@@ -92,7 +194,7 @@ pub(crate) fn get_document_symbols(
                 };
                 let kind = match parent.kind() {
                     // for variable definitions, the Let binding holds an Ident
-                    SyntaxKind::LetBinding => SymbolKind::VARIABLE,
+                    SyntaxKind::LetBinding => LexicalKind::Variable,
                     // for function definitions, the Let binding holds a Closure which holds the
                     // Ident
                     SyntaxKind::Closure => {
@@ -100,25 +202,14 @@ pub(crate) fn get_document_symbols(
                             return Ok(None);
                         };
                         match grand_parent.kind() {
-                            SyntaxKind::LetBinding => SymbolKind::FUNCTION,
+                            SyntaxKind::LetBinding => LexicalKind::Function,
                             _ => return Ok(None),
                         }
                     }
                     _ => return Ok(None),
                 };
-                let symbol = SymbolInformation {
-                    name,
-                    kind,
-                    tags: None,
-                    deprecated: None, // do not use, deprecated, use `tags` instead
-                    location: LspLocation {
-                        uri: uri.clone(),
-                        range: typst_to_lsp::range(node.range(), source, position_encoding)
-                            .raw_range,
-                    },
-                    container_name: None,
-                };
-                Ok(Some(symbol))
+
+                (name, kind)
             }
             SyntaxKind::Markup => {
                 let name = node.get().to_owned().into_text().to_string();
@@ -129,34 +220,114 @@ pub(crate) fn get_document_symbols(
                     return Ok(None);
                 };
                 let kind = match parent.kind() {
-                    SyntaxKind::Heading => SymbolKind::NAMESPACE,
+                    SyntaxKind::Heading => LexicalKind::Namespace(
+                        parent.cast::<ast::Heading>().unwrap().level().get() as i16,
+                    ),
                     _ => return Ok(None),
                 };
-                let symbol = SymbolInformation {
-                    name,
-                    kind,
-                    tags: None,
-                    deprecated: None, // do not use, deprecated, use `tags` instead
-                    location: LspLocation {
-                        uri: uri.clone(),
-                        range: typst_to_lsp::range(node.range(), source, position_encoding)
-                            .raw_range,
-                    },
-                    container_name: None,
-                };
-                Ok(Some(symbol))
+
+                (name, kind)
             }
-            _ => Ok(None),
-        }
+            _ => return Ok(None),
+        };
+
+        Ok(Some(LexicalInfo {
+            name,
+            kind,
+            range: node.range(),
+        }))
     }
 
     let root = LinkedNode::new(source.root());
 
-    let mut worker = DocumentSymbolWorker { symbols: vec![] };
+    let mut worker = LexicalHierarchyWorker {
+        g,
+        ..LexicalHierarchyWorker::default()
+    };
+    worker.stack.push((
+        LexicalInfo {
+            name: "deadbeef".to_string(),
+            kind: LexicalKind::Namespace(-1),
+            range: 0..0,
+        },
+        eco_vec![],
+    ));
+    let res = worker.get_symbols(root).ok();
 
-    let res = worker
-        .get_symbols(root, &source, &uri, position_encoding)
-        .ok();
-
-    res.map(|_| worker.symbols)
+    while worker.stack.len() > 1 {
+        worker.symbreak();
+    }
+    res.map(|_| worker.stack.pop().unwrap().1)
+}
+
+#[cfg(test)]
+mod tests {
+    use insta::assert_snapshot;
+
+    use super::*;
+    use crate::tests::*;
+
+    #[test]
+    fn test_get_document_symbols() {
+        run_with_source(
+            r#"
+= Heading 1
+#let a = 1;
+== Heading 2
+#let b = 1;
+= Heading 3
+#let c = 1;
+#let d = {
+  #let e = 1;
+  0
+}
+"#,
+            |world, path| {
+                let request = DocumentSymbolRequest { path };
+                let result = request.request(world, PositionEncoding::Utf16);
+                assert_snapshot!(JsonRepr::new_redacted(result.unwrap(), &REDACT_LOC), @r###"
+                [
+                 {
+                  "children": [
+                   {
+                    "kind": 13,
+                    "name": "a"
+                   },
+                   {
+                    "children": [
+                     {
+                      "kind": 13,
+                      "name": "b"
+                     }
+                    ],
+                    "kind": 3,
+                    "name": "Heading 2"
+                   }
+                  ],
+                  "kind": 3,
+                  "name": "Heading 1"
+                 },
+                 {
+                  "children": [
+                   {
+                    "kind": 13,
+                    "name": "c"
+                   },
+                   {
+                    "kind": 13,
+                    "name": "d"
+                   },
+                   {
+                    "kind": 13,
+                    "name": "e"
+                   }
+                  ],
+                  "kind": 3,
+                  "name": "Heading 3"
+                 }
+                ]
+                "###);
+            },
+        );
+    }
 }

crates/tinymist-query/src/folding_range.rs

@@ -0,0 +1,38 @@
+use crate::{get_lexical_hierarchy, prelude::*, LexicalScopeGranularity};
+
+#[derive(Debug, Clone)]
+pub struct FoldingRangeRequest {
+    pub path: PathBuf,
+}
+
+impl FoldingRangeRequest {
+    pub fn request(
+        self,
+        world: &TypstSystemWorld,
+        position_encoding: PositionEncoding,
+    ) -> Option<Vec<FoldingRange>> {
+        let source = get_suitable_source_in_workspace(world, &self.path).ok()?;
+
+        let symbols = get_lexical_hierarchy(source, LexicalScopeGranularity::Block)?;
+
+        let _ = symbols;
+        let _ = position_encoding;
+
+        None
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use crate::tests::*;
+
+    #[test]
+    fn test_folding_range_request() {
+        run_with_source("let a = 1;", |world, path| {
+            let request = FoldingRangeRequest { path };
+            let result = request.request(world, PositionEncoding::Utf16);
+            assert_eq!(result, None);
+        });
+    }
+}

crates/tinymist-query/src/lib.rs

@@ -18,6 +18,8 @@ pub(crate) mod hover;
 pub use hover::*;
 pub(crate) mod completion;
 pub use completion::*;
+pub(crate) mod folding_range;
+pub use folding_range::*;
 pub(crate) mod selection_range;
 pub use selection_range::*;
 
@@ -25,3 +27,106 @@ pub mod lsp_typst_boundary;
 pub use lsp_typst_boundary::*;
 
 mod prelude;
+
+#[cfg(test)]
+mod tests {
+    use core::fmt;
+    use std::{
+        collections::HashSet,
+        path::{Path, PathBuf},
+    };
+
+    use once_cell::sync::Lazy;
+    use serde::Serialize;
+    use serde_json::{ser::PrettyFormatter, Serializer, Value};
+    use typst_ts_compiler::ShadowApiExt;
+    pub use typst_ts_compiler::TypstSystemWorld;
+    use typst_ts_core::{config::CompileOpts, Bytes};
+
+    pub fn run_with_source<T>(
+        source: &str,
+        f: impl FnOnce(&mut TypstSystemWorld, PathBuf) -> T,
+    ) -> T {
+        let root = if cfg!(windows) {
+            PathBuf::from("C:\\")
+        } else {
+            PathBuf::from("/")
+        };
+        let mut world = TypstSystemWorld::new(CompileOpts {
+            root_dir: root.clone(),
+            ..Default::default()
+        })
+        .unwrap();
+        let pw = &root.join(Path::new("/main.typ"));
+        world
+            .with_shadow_file(pw, Bytes::from(source.as_bytes()), move |e| {
+                Ok(f(e, pw.to_owned()))
+            })
+            .unwrap()
+    }
+
+    // pub static REDACT_URI: Lazy<RedactFields> = Lazy::new(||
+    // RedactFields::from_iter(["uri"]));
+    pub static REDACT_LOC: Lazy<RedactFields> =
+        Lazy::new(|| RedactFields::from_iter(["location", "range", "selectionRange"]));
+
+    pub struct JsonRepr(Value);
+
+    impl JsonRepr {
+        // pub fn new(v: impl serde::Serialize) -> Self {
+        //     let s = serde_json::to_value(v).unwrap();
+        //     Self(REDACT_URI.redact(s))
+        // }
+
+        pub fn new_redacted(v: impl serde::Serialize, rm: &RedactFields) -> Self {
+            let s = serde_json::to_value(v).unwrap();
+            Self(rm.redact(s))
+        }
+    }
+
+    impl fmt::Display for JsonRepr {
+        fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+            let w = std::io::BufWriter::new(Vec::new());
+            let mut ser = Serializer::with_formatter(w, PrettyFormatter::with_indent(b" "));
+            self.0.serialize(&mut ser).unwrap();
+
+            f.write_str(&String::from_utf8(ser.into_inner().into_inner().unwrap()).unwrap())
+        }
+    }
+
+    pub trait Redact {
+        fn redact(&self, v: Value) -> Value;
+    }
+
+    pub struct RedactFields(HashSet<&'static str>);
+
+    impl FromIterator<&'static str> for RedactFields {
+        fn from_iter<T: IntoIterator<Item = &'static str>>(iter: T) -> Self {
+            Self(iter.into_iter().collect())
+        }
+    }
+
+    impl Redact for RedactFields {
+        fn redact(&self, v: Value) -> Value {
+            match v {
+                Value::Object(mut m) => {
+                    for (_, v) in m.iter_mut() {
+                        *v = self.redact(v.clone());
+                    }
+                    for k in self.0.iter() {
+                        m.remove(*k);
+                    }
+                    Value::Object(m)
+                }
+                Value::Array(mut a) => {
+                    for v in a.iter_mut() {
+                        *v = self.redact(v.clone());
+                    }
+                    Value::Array(a)
+                }
+                Value::String(s) => Value::String(s),
+                v => v,
+            }
+        }
+    }
+}

crates/tinymist-query/src/prelude.rs

@@ -9,10 +9,11 @@ pub use anyhow::anyhow;
 pub use itertools::{Format, Itertools};
 pub use log::{error, trace};
 pub use tower_lsp::lsp_types::{
-    CompletionResponse, DiagnosticRelatedInformation, DocumentSymbolResponse, Documentation, Hover,
-    Location as LspLocation, MarkupContent, MarkupKind, Position as LspPosition, SelectionRange,
-    SemanticTokens, SemanticTokensDelta, SemanticTokensFullDeltaResult, SemanticTokensResult,
-    SignatureHelp, SignatureInformation, SymbolInformation, SymbolKind, Url,
+    CompletionResponse, DiagnosticRelatedInformation, DocumentSymbol, DocumentSymbolResponse,
+    Documentation, FoldingRange, Hover, Location as LspLocation, MarkupContent, MarkupKind,
+    Position as LspPosition, SelectionRange, SemanticTokens, SemanticTokensDelta,
+    SemanticTokensFullDeltaResult, SemanticTokensResult, SignatureHelp, SignatureInformation,
+    SymbolInformation, SymbolKind, Url,
 };
 pub use typst::diag::{EcoString, FileError, FileResult, Tracepoint};
 pub use typst::foundations::{Func, ParamInfo, Value};

crates/tinymist-query/src/symbol.rs

@@ -1,7 +1,7 @@
 use typst_ts_compiler::NotifyApi;
 
-use crate::document_symbol::get_document_symbols;
-use crate::prelude::*;
+use crate::document_symbol::get_lexical_hierarchy;
+use crate::{prelude::*, LexicalHierarchy, LexicalKind, LexicalScopeGranularity};
 
 #[derive(Debug, Clone)]
 pub struct SymbolRequest {
@@ -23,11 +23,12 @@ impl SymbolRequest {
                 return;
             };
             let uri = Url::from_file_path(path).unwrap();
-            let res = get_document_symbols(source, uri, position_encoding).and_then(|symbols| {
-                self.pattern
-                    .as_ref()
-                    .map(|pattern| filter_document_symbols(symbols, pattern))
-            });
+            let res = get_lexical_hierarchy(source.clone(), LexicalScopeGranularity::None)
+                .and_then(|symbols| {
+                    self.pattern.as_ref().map(|pattern| {
+                        filter_document_symbols(&symbols, pattern, &source, &uri, position_encoding)
+                    })
+                });
 
             if let Some(mut res) = res {
                 symbols.append(&mut res)
@@ -38,12 +39,42 @@ impl SymbolRequest {
     }
 }
 
+#[allow(deprecated)]
 fn filter_document_symbols(
-    symbols: Vec<SymbolInformation>,
+    symbols: &[LexicalHierarchy],
     query_string: &str,
+    source: &Source,
+    uri: &Url,
+    position_encoding: PositionEncoding,
 ) -> Vec<SymbolInformation> {
     symbols
-        .into_iter()
-        .filter(|e| e.name.contains(query_string))
+        .iter()
+        .flat_map(|e| {
+            [e].into_iter()
+                .chain(e.children.as_deref().into_iter().flatten())
+        })
+        .filter(|e| e.info.name.contains(query_string))
+        .map(|e| {
+            let rng =
+                typst_to_lsp::range(e.info.range.clone(), source, position_encoding).raw_range;
+
+            SymbolInformation {
+                name: e.info.name.clone(),
+                kind: match e.info.kind {
+                    LexicalKind::Namespace(..) => SymbolKind::NAMESPACE,
+                    LexicalKind::Variable => SymbolKind::VARIABLE,
+                    LexicalKind::Function => SymbolKind::FUNCTION,
+                    LexicalKind::Constant => SymbolKind::CONSTANT,
+                    LexicalKind::Block => unreachable!(),
+                },
+                tags: None,
+                deprecated: None,
+                location: LspLocation {
+                    uri: uri.clone(),
+                    range: rng,
+                },
+                container_name: None,
+            }
+        })
         .collect()
 }

crates/tinymist/Cargo.toml

@@ -34,6 +34,7 @@ typst-assets = { workspace = true, features = ["fonts"] }
 typst-ts-core = { version = "0.4.2-rc6", default-features = false, features = [
     "flat-vector",
     "vector-bbox",
+    "no-content-hint",
 ] }
 typst-ts-compiler.workspace = true
 typst-preview.workspace = true

crates/tinymist/src/actor/typst.rs

@@ -12,7 +12,7 @@ use tinymist_query::{
 };
 use tokio::sync::{broadcast, mpsc, watch, Mutex, RwLock};
 use tower_lsp::lsp_types::{
-    CompletionResponse, DocumentSymbolResponse, Hover, SelectionRange,
+    CompletionResponse, DocumentSymbolResponse, FoldingRange, Hover, SelectionRange,
     SemanticTokensFullDeltaResult, SemanticTokensResult, SignatureHelp, SymbolInformation,
     TextDocumentContentChangeEvent, Url,
 };
@@ -300,6 +300,7 @@ pub enum CompilerQueryRequest {
     Symbol(tinymist_query::SymbolRequest),
     SemanticTokensFull(tinymist_query::SemanticTokensFullRequest),
     SemanticTokensDelta(tinymist_query::SemanticTokensDeltaRequest),
+    FoldingRange(tinymist_query::FoldingRangeRequest),
     SelectionRange(tinymist_query::SelectionRangeRequest),
 }
 
@@ -313,6 +314,7 @@ pub enum CompilerQueryResponse {
     Symbol(Option<Vec<SymbolInformation>>),
     SemanticTokensFull(Option<SemanticTokensResult>),
     SemanticTokensDelta(Option<SemanticTokensFullDeltaResult>),
+    FoldingRange(Option<Vec<FoldingRange>>),
     SelectionRange(Option<Vec<SelectionRange>>),
 }
 
@@ -681,6 +683,7 @@ impl<H: CompilationHandle> CompileNode<H> {
             SignatureHelp(req) => query_world!(self, SignatureHelp, req),
             DocumentSymbol(req) => query_world!(self, DocumentSymbol, req),
             Symbol(req) => query_world!(self, Symbol, req),
+            FoldingRange(req) => query_world!(self, FoldingRange, req),
             SelectionRange(req) => query_world!(self, SelectionRange, req),
             CompilerQueryRequest::SemanticTokensDelta(..)
             | CompilerQueryRequest::SemanticTokensFull(..) => unreachable!(),

crates/tinymist/src/lib.rs

@@ -16,9 +16,9 @@ use once_cell::sync::OnceCell;
 use serde_json::Value as JsonValue;
 use tinymist_query::{
     get_semantic_tokens_options, get_semantic_tokens_registration,
-    get_semantic_tokens_unregistration, CompletionRequest, DocumentSymbolRequest, HoverRequest,
-    PositionEncoding, SelectionRangeRequest, SemanticTokensDeltaRequest, SemanticTokensFullRequest,
-    SignatureHelpRequest, SymbolRequest,
+    get_semantic_tokens_unregistration, CompletionRequest, DocumentSymbolRequest,
+    FoldingRangeRequest, HoverRequest, PositionEncoding, SelectionRangeRequest,
+    SemanticTokensDeltaRequest, SemanticTokensFullRequest, SignatureHelpRequest, SymbolRequest,
 };
 
 use anyhow::bail;
@@ -556,6 +556,16 @@ impl LanguageServer for TypstServer {
         run_query!(self, Symbol, SymbolRequest { pattern })
     }
 
+    async fn folding_range(
+        &self,
+        params: FoldingRangeParams,
+    ) -> jsonrpc::Result<Option<Vec<FoldingRange>>> {
+        let uri = params.text_document.uri;
+        let path = uri.to_file_path().unwrap();
+
+        run_query!(self, FoldingRange, FoldingRangeRequest { path })
+    }
+
     async fn selection_range(
         &self,
         params: SelectionRangeParams,