Merge #2837

2837: Accidentally quadratic r=matklad a=matklad

Our syntax highlighting is accdentally quadratic. Current state of the PR fixes it in a pretty crude way, looks like for the proper fix we need to redo how source-analyzer works. 

**NB:** don't be scared by diff stats, that's mostly a test-data file

Co-authored-by: Aleksey Kladov <aleksey.kladov@gmail.com>

Cargo.lock

@@ -739,7 +739,7 @@ dependencies = [
 
 [[package]]
 name = "once_cell"
-version = "1.2.0"
+version = "1.3.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
 [[package]]
@@ -981,7 +981,7 @@ dependencies = [
  "either 1.5.3 (registry+https://github.com/rust-lang/crates.io-index)",
  "insta 0.12.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "log 0.4.8 (registry+https://github.com/rust-lang/crates.io-index)",
- "once_cell 1.2.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "once_cell 1.3.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "ra_arena 0.1.0",
  "ra_cfg 0.1.0",
  "ra_db 0.1.0",
@@ -1043,7 +1043,7 @@ dependencies = [
  "itertools 0.8.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "join_to_string 0.1.3 (registry+https://github.com/rust-lang/crates.io-index)",
  "log 0.4.8 (registry+https://github.com/rust-lang/crates.io-index)",
- "once_cell 1.2.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "once_cell 1.3.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "proptest 0.9.4 (registry+https://github.com/rust-lang/crates.io-index)",
  "ra_assists 0.1.0",
  "ra_cfg 0.1.0",
@@ -1118,7 +1118,7 @@ dependencies = [
  "itertools 0.8.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "jemalloc-ctl 0.3.3 (registry+https://github.com/rust-lang/crates.io-index)",
  "jemallocator 0.3.2 (registry+https://github.com/rust-lang/crates.io-index)",
- "once_cell 1.2.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "once_cell 1.3.0 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
@@ -1141,7 +1141,7 @@ version = "0.1.0"
 dependencies = [
  "arrayvec 0.5.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "itertools 0.8.2 (registry+https://github.com/rust-lang/crates.io-index)",
- "once_cell 1.2.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "once_cell 1.3.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "ra_parser 0.1.0",
  "ra_text_edit 0.1.0",
  "rowan 0.9.0 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -1864,7 +1864,7 @@ dependencies = [
 "checksum notify 4.0.15 (registry+https://github.com/rust-lang/crates.io-index)" = "80ae4a7688d1fab81c5bf19c64fc8db920be8d519ce6336ed4e7efe024724dbd"
 "checksum num-traits 0.2.11 (registry+https://github.com/rust-lang/crates.io-index)" = "c62be47e61d1842b9170f0fdeec8eba98e60e90e5446449a0545e5152acd7096"
 "checksum num_cpus 1.11.1 (registry+https://github.com/rust-lang/crates.io-index)" = "76dac5ed2a876980778b8b85f75a71b6cbf0db0b1232ee12f826bccb00d09d72"
-"checksum once_cell 1.2.0 (registry+https://github.com/rust-lang/crates.io-index)" = "891f486f630e5c5a4916c7e16c4b24a53e78c860b646e9f8e005e4f16847bfed"
+"checksum once_cell 1.3.0 (registry+https://github.com/rust-lang/crates.io-index)" = "f5941ec2d5ee5916c709580d71553b81a633df245bcc73c04dcbd62152ceefc4"
 "checksum ordermap 0.3.5 (registry+https://github.com/rust-lang/crates.io-index)" = "a86ed3f5f244b372d6b1a00b72ef7f8876d0bc6a78a4c9985c53614041512063"
 "checksum parking_lot 0.10.0 (registry+https://github.com/rust-lang/crates.io-index)" = "92e98c49ab0b7ce5b222f2cc9193fc4efe11c6d0bd4f648e374684a6857b1cfc"
 "checksum parking_lot_core 0.7.0 (registry+https://github.com/rust-lang/crates.io-index)" = "7582838484df45743c8434fbff785e8edf260c28748353d44bc0da32e0ceabf1"

crates/ra_hir/src/lib.rs

@@ -8,7 +8,7 @@
 #![recursion_limit = "512"]
 
 macro_rules! impl_froms {
-    ($e:ident: $($v:ident $(($($sv:ident),*))?),*) => {
+    ($e:ident: $($v:ident $(($($sv:ident),*))?),*$(,)?) => {
         $(
             impl From<$v> for $e {
                 fn from(it: $v) -> $e {
@@ -28,6 +28,7 @@ macro_rules! impl_froms {
 
 pub mod db;
 pub mod source_analyzer;
+pub mod source_binder;
 
 pub mod diagnostics;
 
@@ -47,6 +48,7 @@ pub use crate::{
     from_source::FromSource,
     has_source::HasSource,
     source_analyzer::{PathResolution, ScopeEntryWithSyntax, SourceAnalyzer},
+    source_binder::SourceBinder,
 };
 
 pub use hir_def::{

crates/ra_hir/src/source_analyzer.rs

@@ -14,26 +14,22 @@ use hir_def::{
         BodySourceMap,
     },
     expr::{ExprId, PatId},
-    nameres::ModuleSource,
+    resolver::{self, resolver_for_scope, Resolver, TypeNs, ValueNs},
-    resolver::{self, resolver_for_scope, HasResolver, Resolver, TypeNs, ValueNs},
     DefWithBodyId, TraitId,
 };
 use hir_expand::{
     hygiene::Hygiene, name::AsName, AstId, HirFileId, InFile, MacroCallId, MacroCallKind,
 };
 use hir_ty::{InEnvironment, InferenceResult, TraitEnvironment};
-use ra_prof::profile;
 use ra_syntax::{
     ast::{self, AstNode},
-    match_ast, AstPtr,
+    AstPtr, SyntaxNode, SyntaxNodePtr, SyntaxToken, TextRange, TextUnit,
-    SyntaxKind::*,
-    SyntaxNode, SyntaxNodePtr, SyntaxToken, TextRange, TextUnit,
 };
 use rustc_hash::FxHashSet;
 
 use crate::{
-    db::HirDatabase, Adt, Const, DefWithBody, Enum, EnumVariant, FromSource, Function, ImplBlock,
+    db::HirDatabase, Adt, Const, DefWithBody, EnumVariant, Function, Local, MacroDef, Name, Path,
-    Local, MacroDef, Name, Path, ScopeDef, Static, Struct, Trait, Type, TypeAlias, TypeParam,
+    ScopeDef, Static, Struct, Trait, Type, TypeAlias, TypeParam,
 };
 
 /// `SourceAnalyzer` is a convenience wrapper which exposes HIR API in terms of
@@ -109,31 +105,38 @@ impl SourceAnalyzer {
         node: InFile<&SyntaxNode>,
         offset: Option<TextUnit>,
     ) -> SourceAnalyzer {
-        let _p = profile("SourceAnalyzer::new");
+        crate::source_binder::SourceBinder::new(db).analyze(node, offset)
-        let def_with_body = def_with_body_from_child_node(db, node);
+    }
-        if let Some(def) = def_with_body {
+
-            let (_body, source_map) = db.body_with_source_map(def.into());
+    pub(crate) fn new_for_body(
-            let scopes = db.expr_scopes(def.into());
+        db: &impl HirDatabase,
+        def: DefWithBodyId,
+        node: InFile<&SyntaxNode>,
+        offset: Option<TextUnit>,
+    ) -> SourceAnalyzer {
+        let (_body, source_map) = db.body_with_source_map(def);
+        let scopes = db.expr_scopes(def);
         let scope = match offset {
             None => scope_for(&scopes, &source_map, node),
             Some(offset) => scope_for_offset(&scopes, &source_map, node.with_value(offset)),
         };
-            let resolver = resolver_for_scope(db, def.into(), scope);
+        let resolver = resolver_for_scope(db, def, scope);
         SourceAnalyzer {
             resolver,
-                body_owner: Some(def),
+            body_owner: Some(def.into()),
             body_source_map: Some(source_map),
-                infer: Some(db.infer(def.into())),
+            infer: Some(db.infer(def)),
             scopes: Some(scopes),
             file_id: node.file_id,
         }
-        } else {
+    }
+
+    pub(crate) fn new_for_resolver(
+        resolver: Resolver,
+        node: InFile<&SyntaxNode>,
+    ) -> SourceAnalyzer {
         SourceAnalyzer {
-                resolver: node
+            resolver,
-                    .value
-                    .ancestors()
-                    .find_map(|it| try_get_resolver_for_node(db, node.with_value(&it)))
-                    .unwrap_or_default(),
             body_owner: None,
             body_source_map: None,
             infer: None,
@@ -141,7 +144,6 @@ impl SourceAnalyzer {
             file_id: node.file_id,
         }
     }
-    }
 
     pub fn module(&self) -> Option<crate::code_model::Module> {
         Some(crate::code_model::Module { id: self.resolver.module()? })
@@ -366,64 +368,6 @@ impl SourceAnalyzer {
     }
 }
 
-fn try_get_resolver_for_node(db: &impl HirDatabase, node: InFile<&SyntaxNode>) -> Option<Resolver> {
-    match_ast! {
-        match (node.value) {
-            ast::Module(it) => {
-                let src = node.with_value(it);
-                Some(crate::Module::from_declaration(db, src)?.id.resolver(db))
-            },
-             ast::SourceFile(it) => {
-                let src = node.with_value(ModuleSource::SourceFile(it));
-                Some(crate::Module::from_definition(db, src)?.id.resolver(db))
-            },
-            ast::StructDef(it) => {
-                let src = node.with_value(it);
-                Some(Struct::from_source(db, src)?.id.resolver(db))
-            },
-            ast::EnumDef(it) => {
-                let src = node.with_value(it);
-                Some(Enum::from_source(db, src)?.id.resolver(db))
-            },
-            ast::ImplBlock(it) => {
-                let src = node.with_value(it);
-                Some(ImplBlock::from_source(db, src)?.id.resolver(db))
-            },
-            ast::TraitDef(it) => {
-                let src = node.with_value(it);
-                Some(Trait::from_source(db, src)?.id.resolver(db))
-            },
-            _ => match node.value.kind() {
-                FN_DEF | CONST_DEF | STATIC_DEF => {
-                    let def = def_with_body_from_child_node(db, node)?;
-                    let def = DefWithBodyId::from(def);
-                    Some(def.resolver(db))
-                }
-                // FIXME add missing cases
-                _ => None
-            }
-        }
-    }
-}
-
-fn def_with_body_from_child_node(
-    db: &impl HirDatabase,
-    child: InFile<&SyntaxNode>,
-) -> Option<DefWithBody> {
-    let _p = profile("def_with_body_from_child_node");
-    child.cloned().ancestors_with_macros(db).find_map(|node| {
-        let n = &node.value;
-        match_ast! {
-            match n {
-                ast::FnDef(def)  => { return Function::from_source(db, node.with_value(def)).map(DefWithBody::from); },
-                ast::ConstDef(def) => { return Const::from_source(db, node.with_value(def)).map(DefWithBody::from); },
-                ast::StaticDef(def) => { return Static::from_source(db, node.with_value(def)).map(DefWithBody::from); },
-                _ => { None },
-            }
-        }
-    })
-}
-
 fn scope_for(
     scopes: &ExprScopes,
     source_map: &BodySourceMap,

crates/ra_hir/src/source_binder.rs

@@ -0,0 +1,173 @@
+//! `SourceBinder` should be the main entry point for getting info about source code.
+//! It's main task is to map source syntax trees to hir-level IDs.
+//!
+//! It is intended to subsume `FromSource` and `SourceAnalyzer`.
+
+use hir_def::{
+    child_by_source::ChildBySource,
+    dyn_map::DynMap,
+    keys::{self, Key},
+    resolver::{HasResolver, Resolver},
+    ConstId, DefWithBodyId, EnumId, EnumVariantId, FunctionId, ImplId, ModuleId, StaticId,
+    StructFieldId, StructId, TraitId, TypeAliasId, UnionId, VariantId,
+};
+use hir_expand::InFile;
+use ra_prof::profile;
+use ra_syntax::{ast, match_ast, AstNode, SyntaxNode, TextUnit};
+use rustc_hash::FxHashMap;
+
+use crate::{db::HirDatabase, ModuleSource, SourceAnalyzer};
+
+pub struct SourceBinder<'a, DB> {
+    pub db: &'a DB,
+    child_by_source_cache: FxHashMap<ChildContainer, DynMap>,
+}
+
+impl<DB: HirDatabase> SourceBinder<'_, DB> {
+    pub fn new(db: &DB) -> SourceBinder<DB> {
+        SourceBinder { db, child_by_source_cache: FxHashMap::default() }
+    }
+
+    pub fn analyze(
+        &mut self,
+        src: InFile<&SyntaxNode>,
+        offset: Option<TextUnit>,
+    ) -> SourceAnalyzer {
+        let _p = profile("SourceBinder::analyzer");
+        let container = match self.find_container(src) {
+            Some(it) => it,
+            None => return SourceAnalyzer::new_for_resolver(Resolver::default(), src),
+        };
+
+        let resolver = match container {
+            ChildContainer::DefWithBodyId(def) => {
+                return SourceAnalyzer::new_for_body(self.db, def, src, offset)
+            }
+            ChildContainer::TraitId(it) => it.resolver(self.db),
+            ChildContainer::ImplId(it) => it.resolver(self.db),
+            ChildContainer::ModuleId(it) => it.resolver(self.db),
+            ChildContainer::EnumId(it) => it.resolver(self.db),
+            ChildContainer::VariantId(it) => it.resolver(self.db),
+        };
+        SourceAnalyzer::new_for_resolver(resolver, src)
+    }
+
+    pub fn to_def<D, T>(&mut self, src: InFile<T>) -> Option<D>
+    where
+        D: From<T::ID>,
+        T: ToId,
+    {
+        let id: T::ID = self.to_id(src)?;
+        Some(id.into())
+    }
+
+    fn to_id<T: ToId>(&mut self, src: InFile<T>) -> Option<T::ID> {
+        let container = self.find_container(src.as_ref().map(|it| it.syntax()))?;
+        let db = self.db;
+        let dyn_map =
+            &*self.child_by_source_cache.entry(container).or_insert_with(|| match container {
+                ChildContainer::DefWithBodyId(it) => it.child_by_source(db),
+                ChildContainer::ModuleId(it) => it.child_by_source(db),
+                ChildContainer::TraitId(it) => it.child_by_source(db),
+                ChildContainer::ImplId(it) => it.child_by_source(db),
+                ChildContainer::EnumId(it) => it.child_by_source(db),
+                ChildContainer::VariantId(it) => it.child_by_source(db),
+            });
+        dyn_map[T::KEY].get(&src).copied()
+    }
+
+    fn find_container(&mut self, src: InFile<&SyntaxNode>) -> Option<ChildContainer> {
+        for container in src.cloned().ancestors_with_macros(self.db).skip(1) {
+            let res: ChildContainer = match_ast! {
+                match (container.value) {
+                    ast::TraitDef(it) => {
+                        let def: TraitId = self.to_id(container.with_value(it))?;
+                        def.into()
+                    },
+                    ast::ImplBlock(it) => {
+                        let def: ImplId = self.to_id(container.with_value(it))?;
+                        def.into()
+                    },
+                    ast::FnDef(it) => {
+                        let def: FunctionId = self.to_id(container.with_value(it))?;
+                        DefWithBodyId::from(def).into()
+                    },
+                    ast::StaticDef(it) => {
+                        let def: StaticId = self.to_id(container.with_value(it))?;
+                        DefWithBodyId::from(def).into()
+                    },
+                    ast::ConstDef(it) => {
+                        let def: ConstId = self.to_id(container.with_value(it))?;
+                        DefWithBodyId::from(def).into()
+                    },
+                    ast::EnumDef(it) => {
+                        let def: EnumId = self.to_id(container.with_value(it))?;
+                        def.into()
+                    },
+                    ast::StructDef(it) => {
+                        let def: StructId = self.to_id(container.with_value(it))?;
+                        VariantId::from(def).into()
+                    },
+                    ast::UnionDef(it) => {
+                        let def: UnionId = self.to_id(container.with_value(it))?;
+                        VariantId::from(def).into()
+                    },
+                    // FIXME: handle out-of-line modules here
+                    _ => { continue },
+                }
+            };
+            return Some(res);
+        }
+
+        let module_source = ModuleSource::from_child_node(self.db, src);
+        let c = crate::Module::from_definition(self.db, src.with_value(module_source))?;
+        Some(c.id.into())
+    }
+}
+
+#[derive(Clone, Copy, PartialEq, Eq, Hash, Debug)]
+enum ChildContainer {
+    DefWithBodyId(DefWithBodyId),
+    ModuleId(ModuleId),
+    TraitId(TraitId),
+    ImplId(ImplId),
+    EnumId(EnumId),
+    VariantId(VariantId),
+}
+impl_froms! {
+    ChildContainer:
+    DefWithBodyId,
+    ModuleId,
+    TraitId,
+    ImplId,
+    EnumId,
+    VariantId,
+}
+
+pub trait ToId: Sized + AstNode + 'static {
+    type ID: Sized + Copy + 'static;
+    const KEY: Key<Self, Self::ID>;
+}
+
+macro_rules! to_id_impls {
+    ($(($id:ident, $ast:path, $key:path)),* ,) => {$(
+        impl ToId for $ast {
+            type ID = $id;
+            const KEY: Key<Self, Self::ID> = $key;
+        }
+    )*}
+}
+
+to_id_impls![
+    (StructId, ast::StructDef, keys::STRUCT),
+    (UnionId, ast::UnionDef, keys::UNION),
+    (EnumId, ast::EnumDef, keys::ENUM),
+    (TraitId, ast::TraitDef, keys::TRAIT),
+    (FunctionId, ast::FnDef, keys::FUNCTION),
+    (StaticId, ast::StaticDef, keys::STATIC),
+    (ConstId, ast::ConstDef, keys::CONST),
+    (TypeAliasId, ast::TypeAliasDef, keys::TYPE_ALIAS),
+    (ImplId, ast::ImplBlock, keys::IMPL),
+    (StructFieldId, ast::RecordFieldDef, keys::RECORD_FIELD),
+    (EnumVariantId, ast::EnumVariant, keys::ENUM_VARIANT),
+];

crates/ra_hir_def/src/lib.rs

@@ -332,7 +332,7 @@ pub enum VariantId {
     StructId(StructId),
     UnionId(UnionId),
 }
-impl_froms!(VariantId: EnumVariantId, StructId);
+impl_froms!(VariantId: EnumVariantId, StructId, UnionId);
 
 trait Intern {
     type ID;

crates/ra_ide/src/goto_definition.rs

@@ -1,6 +1,6 @@
 //! FIXME: write short doc here
 
-use hir::{db::AstDatabase, InFile};
+use hir::{db::AstDatabase, InFile, SourceBinder};
 use ra_syntax::{
     ast::{self, DocCommentsOwner},
     match_ast, AstNode,
@@ -72,7 +72,8 @@ pub(crate) fn reference_definition(
 ) -> ReferenceResult {
     use self::ReferenceResult::*;
 
-    let name_kind = classify_name_ref(db, name_ref).map(|d| d.kind);
+    let mut sb = SourceBinder::new(db);
+    let name_kind = classify_name_ref(&mut sb, name_ref).map(|d| d.kind);
     match name_kind {
         Some(Macro(it)) => return Exact(it.to_nav(db)),
         Some(Field(it)) => return Exact(it.to_nav(db)),

crates/ra_ide/src/hover.rs

@@ -1,6 +1,6 @@
 //! FIXME: write short doc here
 
-use hir::{db::AstDatabase, Adt, HasSource, HirDisplay};
+use hir::{db::AstDatabase, Adt, HasSource, HirDisplay, SourceBinder};
 use ra_db::SourceDatabase;
 use ra_syntax::{
     algo::find_covering_element,
@@ -152,13 +152,14 @@ pub(crate) fn hover(db: &RootDatabase, position: FilePosition) -> Option<RangeIn
 
     let mut res = HoverResult::new();
 
+    let mut sb = SourceBinder::new(db);
     if let Some((range, name_kind)) = match_ast! {
         match (token.value.parent()) {
             ast::NameRef(name_ref) => {
-                classify_name_ref(db, token.with_value(&name_ref)).map(|d| (name_ref.syntax().text_range(), d.kind))
+                classify_name_ref(&mut sb, token.with_value(&name_ref)).map(|d| (name_ref.syntax().text_range(), d.kind))
             },
             ast::Name(name) => {
-                classify_name(db, token.with_value(&name)).map(|d| (name.syntax().text_range(), d.kind))
+                classify_name(&mut sb, token.with_value(&name)).map(|d| (name.syntax().text_range(), d.kind))
             },
             _ => None,
         }

crates/ra_ide/src/inlay_hints.rs

@@ -1,6 +1,6 @@
 //! FIXME: write short doc here
 
-use hir::{HirDisplay, SourceAnalyzer};
+use hir::{HirDisplay, SourceAnalyzer, SourceBinder};
 use once_cell::unsync::Lazy;
 use ra_prof::profile;
 use ra_syntax::{
@@ -29,22 +29,23 @@ pub(crate) fn inlay_hints(
     file: &SourceFile,
     max_inlay_hint_length: Option<usize>,
 ) -> Vec<InlayHint> {
+    let mut sb = SourceBinder::new(db);
     file.syntax()
         .descendants()
-        .flat_map(|node| get_inlay_hints(db, file_id, &node, max_inlay_hint_length))
+        .flat_map(|node| get_inlay_hints(&mut sb, file_id, &node, max_inlay_hint_length))
         .flatten()
         .collect()
 }
 
 fn get_inlay_hints(
-    db: &RootDatabase,
+    sb: &mut SourceBinder<RootDatabase>,
     file_id: FileId,
     node: &SyntaxNode,
     max_inlay_hint_length: Option<usize>,
 ) -> Option<Vec<InlayHint>> {
     let _p = profile("get_inlay_hints");
-    let analyzer =
+    let db = sb.db;
-        Lazy::new(|| SourceAnalyzer::new(db, hir::InFile::new(file_id.into(), node), None));
+    let analyzer = Lazy::new(move || sb.analyze(hir::InFile::new(file_id.into(), node), None));
     match_ast! {
         match node {
             ast::LetStmt(it) => {

crates/ra_ide/src/references.rs

@@ -14,7 +14,7 @@ mod name_definition;
 mod rename;
 mod search_scope;
 
-use hir::InFile;
+use hir::{InFile, SourceBinder};
 use once_cell::unsync::Lazy;
 use ra_db::{SourceDatabase, SourceDatabaseExt};
 use ra_prof::profile;
@@ -171,13 +171,14 @@ fn find_name(
     syntax: &SyntaxNode,
     position: FilePosition,
 ) -> Option<RangeInfo<(String, NameDefinition)>> {
+    let mut sb = SourceBinder::new(db);
     if let Some(name) = find_node_at_offset::<ast::Name>(&syntax, position.offset) {
-        let def = classify_name(db, InFile::new(position.file_id.into(), &name))?;
+        let def = classify_name(&mut sb, InFile::new(position.file_id.into(), &name))?;
         let range = name.syntax().text_range();
         return Some(RangeInfo::new(range, (name.text().to_string(), def)));
     }
     let name_ref = find_node_at_offset::<ast::NameRef>(&syntax, position.offset)?;
-    let def = classify_name_ref(db, InFile::new(position.file_id.into(), &name_ref))?;
+    let def = classify_name_ref(&mut sb, InFile::new(position.file_id.into(), &name_ref))?;
     let range = name_ref.syntax().text_range();
     Some(RangeInfo::new(range, (name_ref.text().to_string(), def)))
 }
@@ -195,7 +196,9 @@ fn process_definition(
 
     for (file_id, search_range) in scope {
         let text = db.file_text(file_id);
+
         let parse = Lazy::new(|| SourceFile::parse(&text));
+        let mut sb = Lazy::new(|| SourceBinder::new(db));
 
         for (idx, _) in text.match_indices(pat) {
             let offset = TextUnit::from_usize(idx);
@@ -209,7 +212,11 @@ fn process_definition(
                         continue;
                     }
                 }
-                if let Some(d) = classify_name_ref(db, InFile::new(file_id.into(), &name_ref)) {
+                // FIXME: reuse sb
+                // See https://github.com/rust-lang/rust/pull/68198#issuecomment-574269098
+
+                if let Some(d) = classify_name_ref(&mut sb, InFile::new(file_id.into(), &name_ref))
+                {
                     if d == def {
                         let kind = if name_ref
                             .syntax()
@@ -319,7 +326,7 @@ mod tests {
         check_result(
             refs,
             "Foo STRUCT_DEF FileId(1) [5; 39) [12; 15) Other",
-            &["FileId(1) [142; 145) StructLiteral"],
+            &["FileId(1) [138; 141) StructLiteral"],
         );
     }
 

crates/ra_ide/src/references/classify.rs

@@ -1,6 +1,6 @@
 //! Functions that are used to classify an element from its definition or reference.
 
-use hir::{FromSource, InFile, Module, ModuleSource, PathResolution, SourceAnalyzer};
+use hir::{FromSource, InFile, Module, ModuleSource, PathResolution, SourceBinder};
 use ra_prof::profile;
 use ra_syntax::{ast, match_ast, AstNode};
 use test_utils::tested_by;
@@ -11,7 +11,10 @@ use super::{
 };
 use crate::db::RootDatabase;
 
-pub(crate) fn classify_name(db: &RootDatabase, name: InFile<&ast::Name>) -> Option<NameDefinition> {
+pub(crate) fn classify_name(
+    sb: &mut SourceBinder<RootDatabase>,
+    name: InFile<&ast::Name>,
+) -> Option<NameDefinition> {
     let _p = profile("classify_name");
     let parent = name.value.syntax().parent()?;
 
@@ -19,90 +22,89 @@ pub(crate) fn classify_name(db: &RootDatabase, name: InFile<&ast::Name>) -> Opti
         match parent {
             ast::BindPat(it) => {
                 let src = name.with_value(it);
-                let local = hir::Local::from_source(db, src)?;
+                let local = hir::Local::from_source(sb.db, src)?;
                 Some(NameDefinition {
                     visibility: None,
-                    container: local.module(db),
+                    container: local.module(sb.db),
                     kind: NameKind::Local(local),
                 })
             },
             ast::RecordFieldDef(it) => {
-                let ast = hir::FieldSource::Named(it);
+                let src = name.with_value(it);
-                let src = name.with_value(ast);
+                let field: hir::StructField = sb.to_def(src)?;
-                let field = hir::StructField::from_source(db, src)?;
+                Some(from_struct_field(sb.db, field))
-                Some(from_struct_field(db, field))
             },
             ast::Module(it) => {
                 let def = {
                     if !it.has_semi() {
                         let ast = hir::ModuleSource::Module(it);
                         let src = name.with_value(ast);
-                        hir::Module::from_definition(db, src)
+                        hir::Module::from_definition(sb.db, src)
                     } else {
                         let src = name.with_value(it);
-                        hir::Module::from_declaration(db, src)
+                        hir::Module::from_declaration(sb.db, src)
                     }
                 }?;
-                Some(from_module_def(db, def.into(), None))
+                Some(from_module_def(sb.db, def.into(), None))
             },
             ast::StructDef(it) => {
                 let src = name.with_value(it);
-                let def = hir::Struct::from_source(db, src)?;
+                let def: hir::Struct = sb.to_def(src)?;
-                Some(from_module_def(db, def.into(), None))
+                Some(from_module_def(sb.db, def.into(), None))
             },
             ast::EnumDef(it) => {
                 let src = name.with_value(it);
-                let def = hir::Enum::from_source(db, src)?;
+                let def: hir::Enum = sb.to_def(src)?;
-                Some(from_module_def(db, def.into(), None))
+                Some(from_module_def(sb.db, def.into(), None))
             },
             ast::TraitDef(it) => {
                 let src = name.with_value(it);
-                let def = hir::Trait::from_source(db, src)?;
+                let def: hir::Trait = sb.to_def(src)?;
-                Some(from_module_def(db, def.into(), None))
+                Some(from_module_def(sb.db, def.into(), None))
             },
             ast::StaticDef(it) => {
                 let src = name.with_value(it);
-                let def = hir::Static::from_source(db, src)?;
+                let def: hir::Static = sb.to_def(src)?;
-                Some(from_module_def(db, def.into(), None))
+                Some(from_module_def(sb.db, def.into(), None))
             },
             ast::EnumVariant(it) => {
                 let src = name.with_value(it);
-                let def = hir::EnumVariant::from_source(db, src)?;
+                let def: hir::EnumVariant = sb.to_def(src)?;
-                Some(from_module_def(db, def.into(), None))
+                Some(from_module_def(sb.db, def.into(), None))
             },
             ast::FnDef(it) => {
                 let src = name.with_value(it);
-                let def = hir::Function::from_source(db, src)?;
+                let def: hir::Function = sb.to_def(src)?;
                 if parent.parent().and_then(ast::ItemList::cast).is_some() {
-                    Some(from_assoc_item(db, def.into()))
+                    Some(from_assoc_item(sb.db, def.into()))
                 } else {
-                    Some(from_module_def(db, def.into(), None))
+                    Some(from_module_def(sb.db, def.into(), None))
                 }
             },
             ast::ConstDef(it) => {
                 let src = name.with_value(it);
-                let def = hir::Const::from_source(db, src)?;
+                let def: hir::Const = sb.to_def(src)?;
                 if parent.parent().and_then(ast::ItemList::cast).is_some() {
-                    Some(from_assoc_item(db, def.into()))
+                    Some(from_assoc_item(sb.db, def.into()))
                 } else {
-                    Some(from_module_def(db, def.into(), None))
+                    Some(from_module_def(sb.db, def.into(), None))
                 }
             },
             ast::TypeAliasDef(it) => {
                 let src = name.with_value(it);
-                let def = hir::TypeAlias::from_source(db, src)?;
+                let def: hir::TypeAlias = sb.to_def(src)?;
                 if parent.parent().and_then(ast::ItemList::cast).is_some() {
-                    Some(from_assoc_item(db, def.into()))
+                    Some(from_assoc_item(sb.db, def.into()))
                 } else {
-                    Some(from_module_def(db, def.into(), None))
+                    Some(from_module_def(sb.db, def.into(), None))
                 }
             },
             ast::MacroCall(it) => {
                 let src = name.with_value(it);
-                let def = hir::MacroDef::from_source(db, src.clone())?;
+                let def = hir::MacroDef::from_source(sb.db, src.clone())?;
 
-                let module_src = ModuleSource::from_child_node(db, src.as_ref().map(|it| it.syntax()));
+                let module_src = ModuleSource::from_child_node(sb.db, src.as_ref().map(|it| it.syntax()));
-                let module = Module::from_definition(db, src.with_value(module_src))?;
+                let module = Module::from_definition(sb.db, src.with_value(module_src))?;
 
                 Some(NameDefinition {
                     visibility: None,
@@ -112,10 +114,10 @@ pub(crate) fn classify_name(db: &RootDatabase, name: InFile<&ast::Name>) -> Opti
             },
             ast::TypeParam(it) => {
                 let src = name.with_value(it);
-                let def = hir::TypeParam::from_source(db, src)?;
+                let def = hir::TypeParam::from_source(sb.db, src)?;
                 Some(NameDefinition {
                     visibility: None,
-                    container: def.module(db),
+                    container: def.module(sb.db),
                     kind: NameKind::TypeParam(def),
                 })
             },
@@ -125,25 +127,25 @@ pub(crate) fn classify_name(db: &RootDatabase, name: InFile<&ast::Name>) -> Opti
 }
 
 pub(crate) fn classify_name_ref(
-    db: &RootDatabase,
+    sb: &mut SourceBinder<RootDatabase>,
     name_ref: InFile<&ast::NameRef>,
 ) -> Option<NameDefinition> {
     let _p = profile("classify_name_ref");
 
     let parent = name_ref.value.syntax().parent()?;
-    let analyzer = SourceAnalyzer::new(db, name_ref.map(|it| it.syntax()), None);
+    let analyzer = sb.analyze(name_ref.map(|it| it.syntax()), None);
 
     if let Some(method_call) = ast::MethodCallExpr::cast(parent.clone()) {
         tested_by!(goto_def_for_methods);
         if let Some(func) = analyzer.resolve_method_call(&method_call) {
-            return Some(from_assoc_item(db, func.into()));
+            return Some(from_assoc_item(sb.db, func.into()));
         }
     }
 
     if let Some(field_expr) = ast::FieldExpr::cast(parent.clone()) {
         tested_by!(goto_def_for_fields);
         if let Some(field) = analyzer.resolve_field(&field_expr) {
-            return Some(from_struct_field(db, field));
+            return Some(from_struct_field(sb.db, field));
         }
     }
 
@@ -151,30 +153,32 @@ pub(crate) fn classify_name_ref(
         tested_by!(goto_def_for_record_fields);
         tested_by!(goto_def_for_field_init_shorthand);
         if let Some(field_def) = analyzer.resolve_record_field(&record_field) {
-            return Some(from_struct_field(db, field_def));
+            return Some(from_struct_field(sb.db, field_def));
         }
     }
 
-    let ast = ModuleSource::from_child_node(db, name_ref.with_value(&parent));
+    let ast = ModuleSource::from_child_node(sb.db, name_ref.with_value(&parent));
     // FIXME: find correct container and visibility for each case
-    let container = Module::from_definition(db, name_ref.with_value(ast))?;
+    let container = Module::from_definition(sb.db, name_ref.with_value(ast))?;
     let visibility = None;
 
     if let Some(macro_call) = parent.ancestors().find_map(ast::MacroCall::cast) {
         tested_by!(goto_def_for_macros);
-        if let Some(macro_def) = analyzer.resolve_macro_call(db, name_ref.with_value(&macro_call)) {
+        if let Some(macro_def) =
+            analyzer.resolve_macro_call(sb.db, name_ref.with_value(&macro_call))
+        {
             let kind = NameKind::Macro(macro_def);
             return Some(NameDefinition { kind, container, visibility });
         }
     }
 
     let path = name_ref.value.syntax().ancestors().find_map(ast::Path::cast)?;
-    let resolved = analyzer.resolve_path(db, &path)?;
+    let resolved = analyzer.resolve_path(sb.db, &path)?;
     match resolved {
-        PathResolution::Def(def) => Some(from_module_def(db, def, Some(container))),
+        PathResolution::Def(def) => Some(from_module_def(sb.db, def, Some(container))),
-        PathResolution::AssocItem(item) => Some(from_assoc_item(db, item)),
+        PathResolution::AssocItem(item) => Some(from_assoc_item(sb.db, item)),
         PathResolution::Local(local) => {
-            let container = local.module(db);
+            let container = local.module(sb.db);
             let kind = NameKind::Local(local);
             Some(NameDefinition { kind, container, visibility: None })
         }
@@ -188,7 +192,7 @@ pub(crate) fn classify_name_ref(
         }
         PathResolution::SelfType(impl_block) => {
             let kind = NameKind::SelfType(impl_block);
-            let container = impl_block.module(db);
+            let container = impl_block.module(sb.db);
             Some(NameDefinition { kind, container, visibility })
         }
     }

crates/ra_ide/src/syntax_highlighting.rs

@@ -2,7 +2,7 @@
 
 use rustc_hash::{FxHashMap, FxHashSet};
 
-use hir::{InFile, Name};
+use hir::{InFile, Name, SourceBinder};
 use ra_db::SourceDatabase;
 use ra_prof::profile;
 use ra_syntax::{ast, AstNode, Direction, SyntaxElement, SyntaxKind, SyntaxKind::*, TextRange, T};
@@ -84,6 +84,8 @@ pub(crate) fn highlight(db: &RootDatabase, file_id: FileId) -> Vec<HighlightedRa
         hash((file_id, name, shadow_count))
     }
 
+    let mut sb = SourceBinder::new(db);
+
     // Visited nodes to handle highlighting priorities
     // FIXME: retain only ranges here
     let mut highlighted: FxHashSet<SyntaxElement> = FxHashSet::default();
@@ -108,8 +110,8 @@ pub(crate) fn highlight(db: &RootDatabase, file_id: FileId) -> Vec<HighlightedRa
             NAME_REF if node.ancestors().any(|it| it.kind() == ATTR) => continue,
             NAME_REF => {
                 let name_ref = node.as_node().cloned().and_then(ast::NameRef::cast).unwrap();
-                let name_kind =
+                let name_kind = classify_name_ref(&mut sb, InFile::new(file_id.into(), &name_ref))
-                    classify_name_ref(db, InFile::new(file_id.into(), &name_ref)).map(|d| d.kind);
+                    .map(|d| d.kind);
                 match name_kind {
                     Some(name_kind) => {
                         if let Local(local) = &name_kind {
@@ -129,7 +131,7 @@ pub(crate) fn highlight(db: &RootDatabase, file_id: FileId) -> Vec<HighlightedRa
             NAME => {
                 let name = node.as_node().cloned().and_then(ast::Name::cast).unwrap();
                 let name_kind =
-                    classify_name(db, InFile::new(file_id.into(), &name)).map(|d| d.kind);
+                    classify_name(&mut sb, InFile::new(file_id.into(), &name)).map(|d| d.kind);
 
                 if let Some(Local(local)) = &name_kind {
                     if let Some(name) = local.name(db) {
@@ -308,9 +310,12 @@ pre                 { color: #DCDCCC; background: #3F3F3F; font-size: 22px; padd
 
 #[cfg(test)]
 mod tests {
-    use crate::mock_analysis::single_file;
+    use std::fs;
+
     use test_utils::{assert_eq_text, project_dir, read_text};
 
+    use crate::mock_analysis::{single_file, MockAnalysis};
+
     #[test]
     fn test_highlighting() {
         let (analysis, file_id) = single_file(
@@ -357,7 +362,7 @@ impl<X> E<X> {
         let dst_file = project_dir().join("crates/ra_ide/src/snapshots/highlighting.html");
         let actual_html = &analysis.highlight_as_html(file_id, false).unwrap();
         let expected_html = &read_text(&dst_file);
-        std::fs::write(dst_file, &actual_html).unwrap();
+        fs::write(dst_file, &actual_html).unwrap();
         assert_eq_text!(expected_html, actual_html);
     }
 
@@ -383,7 +388,21 @@ fn bar() {
         let dst_file = project_dir().join("crates/ra_ide/src/snapshots/rainbow_highlighting.html");
         let actual_html = &analysis.highlight_as_html(file_id, true).unwrap();
         let expected_html = &read_text(&dst_file);
-        std::fs::write(dst_file, &actual_html).unwrap();
+        fs::write(dst_file, &actual_html).unwrap();
         assert_eq_text!(expected_html, actual_html);
     }
+
+    #[test]
+    fn accidentally_quadratic() {
+        let file = project_dir().join("crates/ra_syntax/test_data/accidentally_quadratic");
+        let src = fs::read_to_string(file).unwrap();
+
+        let mut mock = MockAnalysis::new();
+        let file_id = mock.add_file("/main.rs", &src);
+        let host = mock.analysis_host();
+
+        // let t = std::time::Instant::now();
+        let _ = host.analysis().highlight(file_id).unwrap();
+        // eprintln!("elapsed: {:?}", t.elapsed());
+    }
 }