1 //! Computes color for a single element.
3 use hir::{AsAssocItem, HasVisibility, Semantics};
5 defs::{Definition, NameClass, NameRefClass},
7 RootDatabase, SymbolKind,
9 use rustc_hash::FxHashMap;
11 ast, match_ast, AstNode, AstToken, NodeOrToken,
12 SyntaxKind::{self, *},
13 SyntaxNode, SyntaxToken, T,
17 syntax_highlighting::tags::{HlOperator, HlPunct},
18 Highlight, HlMod, HlTag,
21 pub(super) fn token(sema: &Semantics<RootDatabase>, token: SyntaxToken) -> Option<Highlight> {
22 if let Some(comment) = ast::Comment::cast(token.clone()) {
23 let h = HlTag::Comment;
24 return Some(match comment.kind().doc {
25 Some(_) => h | HlMod::Documentation,
30 let highlight: Highlight = match token.kind() {
31 STRING | BYTE_STRING => HlTag::StringLiteral.into(),
32 INT_NUMBER if token.ancestors().nth(1).map(|it| it.kind()) == Some(FIELD_EXPR) => {
33 SymbolKind::Field.into()
35 INT_NUMBER | FLOAT_NUMBER => HlTag::NumericLiteral.into(),
36 BYTE => HlTag::ByteLiteral.into(),
37 CHAR => HlTag::CharLiteral.into(),
38 IDENT if token.parent().and_then(ast::TokenTree::cast).is_some() => {
39 // from this point on we are inside a token tree, this only happens for identifiers
40 // that were not mapped down into macro invocations
43 p if p.is_punct() => punctuation(sema, token, p),
44 k if k.is_keyword() => keyword(sema, token, k)?,
51 sema: &Semantics<RootDatabase>,
52 krate: Option<hir::Crate>,
53 bindings_shadow_count: &mut FxHashMap<hir::Name, u32>,
54 syntactic_name_ref_highlighting: bool,
56 ) -> Option<(Highlight, Option<u64>)> {
57 let mut binding_hash = None;
58 let highlight = match_ast! {
60 ast::NameRef(name_ref) => {
64 bindings_shadow_count,
66 syntactic_name_ref_highlighting,
71 highlight_name(sema, bindings_shadow_count, &mut binding_hash, krate, name)
73 ast::Lifetime(lifetime) => {
74 match NameClass::classify_lifetime(sema, &lifetime) {
75 Some(NameClass::Definition(def)) => {
76 highlight_def(sema, krate, def) | HlMod::Definition
78 None => match NameRefClass::classify_lifetime(sema, &lifetime) {
79 Some(NameRefClass::Definition(def)) => highlight_def(sema, krate, def),
80 _ => SymbolKind::LifetimeParam.into(),
82 _ => Highlight::from(SymbolKind::LifetimeParam) | HlMod::Definition,
86 bindings_shadow_count.clear();
90 if [FN, CONST, STATIC].contains(&node.kind()) {
91 bindings_shadow_count.clear();
97 Some((highlight, binding_hash))
100 fn punctuation(sema: &Semantics<RootDatabase>, token: SyntaxToken, kind: SyntaxKind) -> Highlight {
101 let parent = token.parent();
102 let parent_kind = parent.as_ref().map_or(EOF, SyntaxNode::kind);
103 match (kind, parent_kind) {
104 (T![?], _) => HlTag::Operator(HlOperator::Other) | HlMod::ControlFlow,
105 (T![&], BIN_EXPR) => HlOperator::Bitwise.into(),
107 let h = HlTag::Operator(HlOperator::Other).into();
108 let is_unsafe = parent
109 .and_then(ast::RefExpr::cast)
110 .map(|ref_expr| sema.is_unsafe_ref_expr(&ref_expr));
111 if let Some(true) = is_unsafe {
117 (T![::] | T![->] | T![=>] | T![..] | T![=] | T![@] | T![.], _) => HlOperator::Other.into(),
118 (T![!], MACRO_CALL) => HlPunct::MacroBang.into(),
119 (T![!], NEVER_TYPE) => HlTag::BuiltinType.into(),
120 (T![!], PREFIX_EXPR) => HlOperator::Logical.into(),
121 (T![*], PTR_TYPE) => HlTag::Keyword.into(),
122 (T![*], PREFIX_EXPR) => {
123 let is_raw_ptr = (|| {
124 let prefix_expr = parent.and_then(ast::PrefixExpr::cast)?;
125 let expr = prefix_expr.expr()?;
126 sema.type_of_expr(&expr)?.original.is_raw_ptr().then(|| ())
128 if let Some(()) = is_raw_ptr {
129 HlTag::Operator(HlOperator::Other) | HlMod::Unsafe
131 HlOperator::Other.into()
134 (T![-], PREFIX_EXPR) => {
135 let prefix_expr = parent.and_then(ast::PrefixExpr::cast).and_then(|e| e.expr());
137 Some(ast::Expr::Literal(_)) => HlTag::NumericLiteral,
138 _ => HlTag::Operator(HlOperator::Other),
142 (T![+] | T![-] | T![*] | T![/], BIN_EXPR) => HlOperator::Arithmetic.into(),
143 (T![+=] | T![-=] | T![*=] | T![/=], BIN_EXPR) => {
144 Highlight::from(HlOperator::Arithmetic) | HlMod::Mutable
146 (T![|] | T![&] | T![!] | T![^], BIN_EXPR) => HlOperator::Bitwise.into(),
147 (T![|=] | T![&=] | T![^=], BIN_EXPR) => {
148 Highlight::from(HlOperator::Bitwise) | HlMod::Mutable
150 (T![&&] | T![||], BIN_EXPR) => HlOperator::Logical.into(),
151 (T![>] | T![<] | T![==] | T![>=] | T![<=] | T![!=], BIN_EXPR) => {
152 HlOperator::Comparison.into()
154 (_, PREFIX_EXPR | BIN_EXPR | RANGE_EXPR | RANGE_PAT | REST_PAT) => HlOperator::Other.into(),
155 (_, ATTR) => HlTag::AttributeBracket.into(),
156 (kind, _) => match kind {
157 T!['['] | T![']'] => HlPunct::Bracket,
158 T!['{'] | T!['}'] => HlPunct::Brace,
159 T!['('] | T![')'] => HlPunct::Parenthesis,
160 T![<] | T![>] => HlPunct::Angle,
161 T![,] => HlPunct::Comma,
162 T![:] => HlPunct::Colon,
163 T![;] => HlPunct::Semi,
164 T![.] => HlPunct::Dot,
172 sema: &Semantics<RootDatabase>,
175 ) -> Option<Highlight> {
176 let h = Highlight::new(HlTag::Keyword);
178 T![await] => h | HlMod::Async | HlMod::ControlFlow,
179 T![async] => h | HlMod::Async,
189 | T![yield] => h | HlMod::ControlFlow,
190 T![for] if parent_matches::<ast::ForExpr>(&token) => h | HlMod::ControlFlow,
191 T![unsafe] => h | HlMod::Unsafe,
192 T![true] | T![false] => HlTag::BoolLiteral.into(),
193 // crate is handled just as a token if it's in an `extern crate`
194 T![crate] if parent_matches::<ast::ExternCrate>(&token) => h,
195 // self, crate and super are handled as either a Name or NameRef already, unless they
196 // are inside unmapped token trees
197 T![self] | T![crate] | T![super] if parent_matches::<ast::NameRef>(&token) => return None,
198 T![self] if parent_matches::<ast::Name>(&token) => return None,
199 T![ref] => match token.parent().and_then(ast::IdentPat::cast) {
200 Some(ident) if sema.is_unsafe_ident_pat(&ident) => h | HlMod::Unsafe,
208 fn highlight_name_ref(
209 sema: &Semantics<RootDatabase>,
210 krate: Option<hir::Crate>,
211 bindings_shadow_count: &mut FxHashMap<hir::Name, u32>,
212 binding_hash: &mut Option<u64>,
213 syntactic_name_ref_highlighting: bool,
214 name_ref: ast::NameRef,
217 if let Some(res) = highlight_method_call_by_name_ref(sema, krate, &name_ref) {
221 let name_class = match NameRefClass::classify(sema, &name_ref) {
222 Some(name_kind) => name_kind,
223 None if syntactic_name_ref_highlighting => {
224 return highlight_name_ref_by_syntax(name_ref, sema, krate)
226 // FIXME: This is required for helper attributes used by proc-macros, as those do not map down
227 // to anything when used.
228 // We can fix this for derive attributes since derive helpers are recorded, but not for
229 // general attributes.
230 None if name_ref.syntax().ancestors().any(|it| it.kind() == ATTR) => {
231 return HlTag::Symbol(SymbolKind::Attribute).into();
233 None => return HlTag::UnresolvedReference.into(),
235 let mut h = match name_class {
236 NameRefClass::Definition(def) => {
237 if let Definition::Local(local) = &def {
238 if let Some(name) = local.name(db) {
239 let shadow_count = bindings_shadow_count.entry(name.clone()).or_default();
240 *binding_hash = Some(calc_binding_hash(&name, *shadow_count))
244 let mut h = highlight_def(sema, krate, def);
247 Definition::Local(local) if is_consumed_lvalue(name_ref.syntax(), &local, db) => {
248 h |= HlMod::Consuming;
250 Definition::Trait(trait_) if trait_.is_unsafe(db) => {
251 if ast::Impl::for_trait_name_ref(&name_ref)
252 .map_or(false, |impl_| impl_.unsafe_token().is_some())
257 Definition::Field(field) => {
258 if let Some(parent) = name_ref.syntax().parent() {
259 if matches!(parent.kind(), FIELD_EXPR | RECORD_PAT_FIELD) {
260 if let hir::VariantDef::Union(_) = field.parent_def(db) {
271 NameRefClass::FieldShorthand { .. } => SymbolKind::Field.into(),
273 if name_ref.self_token().is_some() {
274 h.tag = HlTag::Symbol(SymbolKind::SelfParam);
276 if name_ref.crate_token().is_some() || name_ref.super_token().is_some() {
277 h.tag = HlTag::Keyword;
283 sema: &Semantics<RootDatabase>,
284 bindings_shadow_count: &mut FxHashMap<hir::Name, u32>,
285 binding_hash: &mut Option<u64>,
286 krate: Option<hir::Crate>,
289 let name_kind = NameClass::classify(sema, &name);
290 if let Some(NameClass::Definition(Definition::Local(local))) = &name_kind {
291 if let Some(name) = local.name(sema.db) {
292 let shadow_count = bindings_shadow_count.entry(name.clone()).or_default();
294 *binding_hash = Some(calc_binding_hash(&name, *shadow_count))
298 Some(NameClass::Definition(def)) => {
299 let mut h = highlight_def(sema, krate, def) | HlMod::Definition;
300 if let Definition::Trait(trait_) = &def {
301 if trait_.is_unsafe(sema.db) {
307 Some(NameClass::ConstReference(def)) => highlight_def(sema, krate, def),
308 Some(NameClass::PatFieldShorthand { field_ref, .. }) => {
309 let mut h = HlTag::Symbol(SymbolKind::Field).into();
310 if let hir::VariantDef::Union(_) = field_ref.parent_def(sema.db) {
315 None => highlight_name_by_syntax(name) | HlMod::Definition,
319 fn calc_binding_hash(name: &hir::Name, shadow_count: u32) -> u64 {
320 fn hash<T: std::hash::Hash + std::fmt::Debug>(x: T) -> u64 {
321 use std::{collections::hash_map::DefaultHasher, hash::Hasher};
323 let mut hasher = DefaultHasher::new();
328 hash((name, shadow_count))
332 sema: &Semantics<RootDatabase>,
333 krate: Option<hir::Crate>,
337 let mut h = match def {
338 Definition::Macro(m) => Highlight::new(HlTag::Symbol(m.kind().into())),
339 Definition::Field(_) => Highlight::new(HlTag::Symbol(SymbolKind::Field)),
340 Definition::Module(module) => {
341 let mut h = Highlight::new(HlTag::Symbol(SymbolKind::Module));
342 if module.parent(db).is_none() {
343 h |= HlMod::CrateRoot
347 Definition::Function(func) => {
348 let mut h = Highlight::new(HlTag::Symbol(SymbolKind::Function));
349 if let Some(item) = func.as_assoc_item(db) {
350 h |= HlMod::Associated;
351 match func.self_param(db) {
352 Some(sp) => match sp.access(db) {
353 hir::Access::Exclusive => {
355 h |= HlMod::Reference;
357 hir::Access::Shared => h |= HlMod::Reference,
358 hir::Access::Owned => h |= HlMod::Consuming,
360 None => h |= HlMod::Static,
363 match item.container(db) {
364 hir::AssocItemContainer::Impl(i) => {
365 if i.trait_(db).is_some() {
369 hir::AssocItemContainer::Trait(_t) => {
375 if func.is_unsafe(db) {
378 if func.is_async(db) {
384 Definition::Adt(adt) => {
386 hir::Adt::Struct(_) => HlTag::Symbol(SymbolKind::Struct),
387 hir::Adt::Enum(_) => HlTag::Symbol(SymbolKind::Enum),
388 hir::Adt::Union(_) => HlTag::Symbol(SymbolKind::Union),
393 Definition::Variant(_) => Highlight::new(HlTag::Symbol(SymbolKind::Variant)),
394 Definition::Const(konst) => {
395 let mut h = Highlight::new(HlTag::Symbol(SymbolKind::Const));
397 if let Some(item) = konst.as_assoc_item(db) {
398 h |= HlMod::Associated;
399 match item.container(db) {
400 hir::AssocItemContainer::Impl(i) => {
401 if i.trait_(db).is_some() {
405 hir::AssocItemContainer::Trait(_t) => {
413 Definition::Trait(_) => Highlight::new(HlTag::Symbol(SymbolKind::Trait)),
414 Definition::TypeAlias(type_) => {
415 let mut h = Highlight::new(HlTag::Symbol(SymbolKind::TypeAlias));
417 if let Some(item) = type_.as_assoc_item(db) {
418 h |= HlMod::Associated;
419 match item.container(db) {
420 hir::AssocItemContainer::Impl(i) => {
421 if i.trait_(db).is_some() {
425 hir::AssocItemContainer::Trait(_t) => {
433 Definition::BuiltinType(_) => Highlight::new(HlTag::BuiltinType),
434 Definition::Static(s) => {
435 let mut h = Highlight::new(HlTag::Symbol(SymbolKind::Static));
444 Definition::SelfType(_) => Highlight::new(HlTag::Symbol(SymbolKind::Impl)),
445 Definition::GenericParam(it) => match it {
446 hir::GenericParam::TypeParam(_) => Highlight::new(HlTag::Symbol(SymbolKind::TypeParam)),
447 hir::GenericParam::ConstParam(_) => {
448 Highlight::new(HlTag::Symbol(SymbolKind::ConstParam))
450 hir::GenericParam::LifetimeParam(_) => {
451 Highlight::new(HlTag::Symbol(SymbolKind::LifetimeParam))
454 Definition::Local(local) => {
455 let tag = if local.is_self(db) {
456 HlTag::Symbol(SymbolKind::SelfParam)
457 } else if local.is_param(db) {
458 HlTag::Symbol(SymbolKind::ValueParam)
460 HlTag::Symbol(SymbolKind::Local)
462 let mut h = Highlight::new(tag);
463 let ty = local.ty(db);
464 if local.is_mut(db) || ty.is_mutable_reference() {
467 if local.is_ref(db) || ty.is_reference() {
468 h |= HlMod::Reference;
470 if ty.as_callable(db).is_some() || ty.impls_fnonce(db) {
471 h |= HlMod::Callable;
475 Definition::Label(_) => Highlight::new(HlTag::Symbol(SymbolKind::Label)),
476 Definition::BuiltinAttr(_) => Highlight::new(HlTag::Symbol(SymbolKind::BuiltinAttr)),
477 Definition::ToolModule(_) => Highlight::new(HlTag::Symbol(SymbolKind::ToolModule)),
480 let famous_defs = FamousDefs(sema, krate);
481 let def_crate = def.module(db).map(hir::Module::krate).or_else(|| match def {
482 Definition::Module(module) => Some(module.krate()),
485 let is_from_other_crate = def_crate != krate;
486 let is_from_builtin_crate =
487 def_crate.map_or(false, |def_crate| famous_defs.builtin_crates().any(|it| def_crate == it));
488 let is_builtin_type = matches!(def, Definition::BuiltinType(_));
489 let is_public = def.visibility(db) == Some(hir::Visibility::Public);
491 match (is_from_other_crate, is_builtin_type, is_public) {
492 (true, false, _) => h |= HlMod::Library,
493 (false, _, true) => h |= HlMod::Public,
497 if is_from_builtin_crate {
498 h |= HlMod::DefaultLibrary;
504 fn highlight_method_call_by_name_ref(
505 sema: &Semantics<RootDatabase>,
506 krate: Option<hir::Crate>,
507 name_ref: &ast::NameRef,
508 ) -> Option<Highlight> {
509 let mc = name_ref.syntax().parent().and_then(ast::MethodCallExpr::cast)?;
510 highlight_method_call(sema, krate, &mc)
513 fn highlight_method_call(
514 sema: &Semantics<RootDatabase>,
515 krate: Option<hir::Crate>,
516 method_call: &ast::MethodCallExpr,
517 ) -> Option<Highlight> {
518 let func = sema.resolve_method_call(method_call)?;
520 let mut h = SymbolKind::Function.into();
521 h |= HlMod::Associated;
523 if func.is_unsafe(sema.db) || sema.is_unsafe_method_call(method_call) {
526 if func.is_async(sema.db) {
529 if func.as_assoc_item(sema.db).and_then(|it| it.containing_trait(sema.db)).is_some() {
533 let famous_defs = FamousDefs(sema, krate);
534 let def_crate = func.module(sema.db).krate();
535 let is_from_other_crate = Some(def_crate) != krate;
536 let is_from_builtin_crate = famous_defs.builtin_crates().any(|it| def_crate == it);
537 let is_public = func.visibility(sema.db) == hir::Visibility::Public;
539 if is_from_other_crate {
541 } else if is_public {
545 if is_from_builtin_crate {
546 h |= HlMod::DefaultLibrary;
549 if let Some(self_param) = func.self_param(sema.db) {
550 match self_param.access(sema.db) {
551 hir::Access::Shared => h |= HlMod::Reference,
552 hir::Access::Exclusive => {
554 h |= HlMod::Reference;
556 hir::Access::Owned => {
557 if let Some(receiver_ty) =
558 method_call.receiver().and_then(|it| sema.type_of_expr(&it))
560 if !receiver_ty.adjusted().is_copy(sema.db) {
561 h |= HlMod::Consuming
570 fn highlight_name_by_syntax(name: ast::Name) -> Highlight {
571 let default = HlTag::UnresolvedReference;
573 let parent = match name.syntax().parent() {
575 _ => return default.into(),
578 let tag = match parent.kind() {
579 STRUCT => SymbolKind::Struct,
580 ENUM => SymbolKind::Enum,
581 VARIANT => SymbolKind::Variant,
582 UNION => SymbolKind::Union,
583 TRAIT => SymbolKind::Trait,
584 TYPE_ALIAS => SymbolKind::TypeAlias,
585 TYPE_PARAM => SymbolKind::TypeParam,
586 RECORD_FIELD => SymbolKind::Field,
587 MODULE => SymbolKind::Module,
588 FN => SymbolKind::Function,
589 CONST => SymbolKind::Const,
590 STATIC => SymbolKind::Static,
591 IDENT_PAT => SymbolKind::Local,
592 _ => return default.into(),
598 fn highlight_name_ref_by_syntax(
600 sema: &Semantics<RootDatabase>,
601 krate: Option<hir::Crate>,
603 let default = HlTag::UnresolvedReference;
605 let parent = match name.syntax().parent() {
607 _ => return default.into(),
610 match parent.kind() {
611 METHOD_CALL_EXPR => ast::MethodCallExpr::cast(parent)
612 .and_then(|it| highlight_method_call(sema, krate, &it))
613 .unwrap_or_else(|| SymbolKind::Function.into()),
615 let h = HlTag::Symbol(SymbolKind::Field);
616 let is_union = ast::FieldExpr::cast(parent)
617 .and_then(|field_expr| sema.resolve_field(&field_expr))
618 .map_or(false, |field| {
619 matches!(field.parent_def(sema.db), hir::VariantDef::Union(_))
628 let name_based_fallback = || {
629 if name.text().chars().next().unwrap_or_default().is_uppercase() {
630 SymbolKind::Struct.into()
632 SymbolKind::Module.into()
635 let path = match parent.parent().and_then(ast::Path::cast) {
637 _ => return name_based_fallback(),
639 let expr = match path.syntax().parent() {
640 Some(parent) => match_ast! {
642 ast::PathExpr(path) => path,
643 ast::MacroCall(_) => return SymbolKind::Macro.into(),
644 _ => return name_based_fallback(),
647 // within path, decide whether it is module or adt by checking for uppercase name
648 None => return name_based_fallback(),
650 let parent = match expr.syntax().parent() {
652 None => return default.into(),
655 match parent.kind() {
656 CALL_EXPR => SymbolKind::Function.into(),
657 _ => if name.text().chars().next().unwrap_or_default().is_uppercase() {
669 fn is_consumed_lvalue(node: &SyntaxNode, local: &hir::Local, db: &RootDatabase) -> bool {
670 // When lvalues are passed as arguments and they're not Copy, then mark them as Consuming.
671 parents_match(node.clone().into(), &[PATH_SEGMENT, PATH, PATH_EXPR, ARG_LIST])
672 && !local.ty(db).is_copy(db)
675 /// Returns true if the parent nodes of `node` all match the `SyntaxKind`s in `kinds` exactly.
676 fn parents_match(mut node: NodeOrToken<SyntaxNode, SyntaxToken>, mut kinds: &[SyntaxKind]) -> bool {
677 while let (Some(parent), [kind, rest @ ..]) = (&node.parent(), kinds) {
678 if parent.kind() != *kind {
682 // FIXME: Would be nice to get parent out of the match, but binding by-move and by-value
683 // in the same pattern is unstable: rust-lang/rust#68354.
684 node = node.parent().unwrap().into();
688 // Only true if we matched all expected kinds
692 fn parent_matches<N: AstNode>(token: &SyntaxToken) -> bool {
693 token.parent().map_or(false, |it| N::can_cast(it.kind()))