1 //! Computes color for a single element.
3 use hir::{AsAssocItem, HasVisibility, Semantics};
5 defs::{Definition, NameClass, NameRefClass},
6 helpers::{try_resolve_derive_input, FamousDefs},
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,
22 sema: &Semantics<RootDatabase>,
23 krate: Option<hir::Crate>,
25 ) -> Option<Highlight> {
26 if let Some(comment) = ast::Comment::cast(token.clone()) {
27 let h = HlTag::Comment;
28 return Some(match comment.kind().doc {
29 Some(_) => h | HlMod::Documentation,
34 let highlight: Highlight = match token.kind() {
35 STRING | BYTE_STRING => HlTag::StringLiteral.into(),
36 INT_NUMBER if token.ancestors().nth(1).map(|it| it.kind()) == Some(FIELD_EXPR) => {
37 SymbolKind::Field.into()
39 INT_NUMBER | FLOAT_NUMBER => HlTag::NumericLiteral.into(),
40 BYTE => HlTag::ByteLiteral.into(),
41 CHAR => HlTag::CharLiteral.into(),
42 IDENT if parent_matches::<ast::TokenTree>(&token) => {
43 match token.ancestors().nth(2).and_then(ast::Attr::cast) {
45 match try_resolve_derive_input(sema, &attr, &ast::Ident::cast(token).unwrap()) {
46 Some(res) => highlight_def(sema, krate, Definition::from(res)),
47 None => HlTag::None.into(),
50 None => HlTag::None.into(),
53 p if p.is_punct() => punctuation(sema, token, p),
54 k if k.is_keyword() => keyword(sema, token, k)?,
61 sema: &Semantics<RootDatabase>,
62 krate: Option<hir::Crate>,
63 bindings_shadow_count: &mut FxHashMap<hir::Name, u32>,
64 syntactic_name_ref_highlighting: bool,
66 ) -> Option<(Highlight, Option<u64>)> {
67 let mut binding_hash = None;
68 let highlight = match_ast! {
70 ast::NameRef(name_ref) => {
74 bindings_shadow_count,
76 syntactic_name_ref_highlighting,
81 highlight_name(sema, bindings_shadow_count, &mut binding_hash, krate, name)
83 ast::Lifetime(lifetime) => {
84 match NameClass::classify_lifetime(sema, &lifetime) {
85 Some(NameClass::Definition(def)) => {
86 highlight_def(sema, krate, def) | HlMod::Definition
88 None => match NameRefClass::classify_lifetime(sema, &lifetime) {
89 Some(NameRefClass::Definition(def)) => highlight_def(sema, krate, def),
90 _ => SymbolKind::LifetimeParam.into(),
92 _ => Highlight::from(SymbolKind::LifetimeParam) | HlMod::Definition,
96 bindings_shadow_count.clear();
100 if [FN, CONST, STATIC].contains(&node.kind()) {
101 bindings_shadow_count.clear();
107 Some((highlight, binding_hash))
110 fn punctuation(sema: &Semantics<RootDatabase>, token: SyntaxToken, kind: SyntaxKind) -> Highlight {
111 let parent = token.parent();
112 let parent_kind = parent.as_ref().map_or(EOF, SyntaxNode::kind);
113 match (kind, parent_kind) {
114 (T![?], _) => HlTag::Operator(HlOperator::Other) | HlMod::ControlFlow,
115 (T![&], BIN_EXPR) => HlOperator::Bitwise.into(),
117 let h = HlTag::Operator(HlOperator::Other).into();
118 let is_unsafe = parent
119 .and_then(ast::RefExpr::cast)
120 .map(|ref_expr| sema.is_unsafe_ref_expr(&ref_expr));
121 if let Some(true) = is_unsafe {
127 (T![::] | T![->] | T![=>] | T![..] | T![=] | T![@] | T![.], _) => HlOperator::Other.into(),
128 (T![!], MACRO_CALL) => HlPunct::MacroBang.into(),
129 (T![!], NEVER_TYPE) => HlTag::BuiltinType.into(),
130 (T![!], PREFIX_EXPR) => HlOperator::Logical.into(),
131 (T![*], PTR_TYPE) => HlTag::Keyword.into(),
132 (T![*], PREFIX_EXPR) => {
133 let is_raw_ptr = (|| {
134 let prefix_expr = parent.and_then(ast::PrefixExpr::cast)?;
135 let expr = prefix_expr.expr()?;
136 sema.type_of_expr(&expr)?.original.is_raw_ptr().then(|| ())
138 if let Some(()) = is_raw_ptr {
139 HlTag::Operator(HlOperator::Other) | HlMod::Unsafe
141 HlOperator::Other.into()
144 (T![-], PREFIX_EXPR) => {
145 let prefix_expr = parent.and_then(ast::PrefixExpr::cast).and_then(|e| e.expr());
147 Some(ast::Expr::Literal(_)) => HlTag::NumericLiteral,
148 _ => HlTag::Operator(HlOperator::Other),
152 (T![+] | T![-] | T![*] | T![/], BIN_EXPR) => HlOperator::Arithmetic.into(),
153 (T![+=] | T![-=] | T![*=] | T![/=], BIN_EXPR) => {
154 Highlight::from(HlOperator::Arithmetic) | HlMod::Mutable
156 (T![|] | T![&] | T![!] | T![^], BIN_EXPR) => HlOperator::Bitwise.into(),
157 (T![|=] | T![&=] | T![^=], BIN_EXPR) => {
158 Highlight::from(HlOperator::Bitwise) | HlMod::Mutable
160 (T![&&] | T![||], BIN_EXPR) => HlOperator::Logical.into(),
161 (T![>] | T![<] | T![==] | T![>=] | T![<=] | T![!=], BIN_EXPR) => {
162 HlOperator::Comparison.into()
164 (_, PREFIX_EXPR | BIN_EXPR | RANGE_EXPR | RANGE_PAT | REST_PAT) => HlOperator::Other.into(),
165 (_, ATTR) => HlTag::AttributeBracket.into(),
166 (kind, _) => match kind {
167 T!['['] | T![']'] => HlPunct::Bracket,
168 T!['{'] | T!['}'] => HlPunct::Brace,
169 T!['('] | T![')'] => HlPunct::Parenthesis,
170 T![<] | T![>] => HlPunct::Angle,
171 T![,] => HlPunct::Comma,
172 T![:] => HlPunct::Colon,
173 T![;] => HlPunct::Semi,
174 T![.] => HlPunct::Dot,
182 sema: &Semantics<RootDatabase>,
185 ) -> Option<Highlight> {
186 let h = Highlight::new(HlTag::Keyword);
188 T![await] => h | HlMod::Async | HlMod::ControlFlow,
189 T![async] => h | HlMod::Async,
199 | T![yield] => h | HlMod::ControlFlow,
200 T![for] if parent_matches::<ast::ForExpr>(&token) => h | HlMod::ControlFlow,
201 T![unsafe] => h | HlMod::Unsafe,
202 T![true] | T![false] => HlTag::BoolLiteral.into(),
203 // crate is handled just as a token if it's in an `extern crate`
204 T![crate] if parent_matches::<ast::ExternCrate>(&token) => h,
205 // self, crate and super are handled as either a Name or NameRef already, unless they
206 // are inside unmapped token trees
207 T![self] | T![crate] | T![super] if parent_matches::<ast::NameRef>(&token) => return None,
208 T![self] if parent_matches::<ast::Name>(&token) => return None,
209 T![ref] => match token.parent().and_then(ast::IdentPat::cast) {
210 Some(ident) if sema.is_unsafe_ident_pat(&ident) => h | HlMod::Unsafe,
218 fn highlight_name_ref(
219 sema: &Semantics<RootDatabase>,
220 krate: Option<hir::Crate>,
221 bindings_shadow_count: &mut FxHashMap<hir::Name, u32>,
222 binding_hash: &mut Option<u64>,
223 syntactic_name_ref_highlighting: bool,
224 name_ref: ast::NameRef,
227 if let Some(res) = highlight_method_call_by_name_ref(sema, krate, &name_ref) {
231 let name_class = match NameRefClass::classify(sema, &name_ref) {
232 Some(name_kind) => name_kind,
233 None if syntactic_name_ref_highlighting => {
234 return highlight_name_ref_by_syntax(name_ref, sema, krate)
236 // FIXME: Workaround for https://github.com/rust-analyzer/rust-analyzer/issues/10708
238 // Some popular proc macros (namely async_trait) will rewrite `self` in such a way that it no
239 // longer resolves via NameRefClass. If we can't be resolved, but we know we're a self token,
240 // within a function with a self param, pretend to still be `self`, rather than
241 // an unresolved reference.
242 None if name_ref.self_token().is_some() && is_in_fn_with_self_param(&name_ref) => {
243 return SymbolKind::SelfParam.into()
245 // FIXME: This is required for helper attributes used by proc-macros, as those do not map down
246 // to anything when used.
247 // We can fix this for derive attributes since derive helpers are recorded, but not for
248 // general attributes.
249 None if name_ref.syntax().ancestors().any(|it| it.kind() == ATTR) => {
250 return HlTag::Symbol(SymbolKind::Attribute).into();
252 None => return HlTag::UnresolvedReference.into(),
254 let mut h = match name_class {
255 NameRefClass::Definition(def) => {
256 if let Definition::Local(local) = &def {
257 if let Some(name) = local.name(db) {
258 let shadow_count = bindings_shadow_count.entry(name.clone()).or_default();
259 *binding_hash = Some(calc_binding_hash(&name, *shadow_count))
263 let mut h = highlight_def(sema, krate, def);
266 Definition::Local(local) if is_consumed_lvalue(name_ref.syntax(), &local, db) => {
267 h |= HlMod::Consuming;
269 Definition::Trait(trait_) if trait_.is_unsafe(db) => {
270 if ast::Impl::for_trait_name_ref(&name_ref)
271 .map_or(false, |impl_| impl_.unsafe_token().is_some())
276 Definition::Field(field) => {
277 if let Some(parent) = name_ref.syntax().parent() {
278 if matches!(parent.kind(), FIELD_EXPR | RECORD_PAT_FIELD) {
279 if let hir::VariantDef::Union(_) = field.parent_def(db) {
290 NameRefClass::FieldShorthand { .. } => SymbolKind::Field.into(),
292 if name_ref.self_token().is_some() {
293 h.tag = HlTag::Symbol(SymbolKind::SelfParam);
295 if name_ref.crate_token().is_some() || name_ref.super_token().is_some() {
296 h.tag = HlTag::Keyword;
302 sema: &Semantics<RootDatabase>,
303 bindings_shadow_count: &mut FxHashMap<hir::Name, u32>,
304 binding_hash: &mut Option<u64>,
305 krate: Option<hir::Crate>,
308 let name_kind = NameClass::classify(sema, &name);
309 if let Some(NameClass::Definition(Definition::Local(local))) = &name_kind {
310 if let Some(name) = local.name(sema.db) {
311 let shadow_count = bindings_shadow_count.entry(name.clone()).or_default();
313 *binding_hash = Some(calc_binding_hash(&name, *shadow_count))
317 Some(NameClass::Definition(def)) => {
318 let mut h = highlight_def(sema, krate, def) | HlMod::Definition;
319 if let Definition::Trait(trait_) = &def {
320 if trait_.is_unsafe(sema.db) {
326 Some(NameClass::ConstReference(def)) => highlight_def(sema, krate, def),
327 Some(NameClass::PatFieldShorthand { field_ref, .. }) => {
328 let mut h = HlTag::Symbol(SymbolKind::Field).into();
329 if let hir::VariantDef::Union(_) = field_ref.parent_def(sema.db) {
334 None => highlight_name_by_syntax(name) | HlMod::Definition,
338 fn calc_binding_hash(name: &hir::Name, shadow_count: u32) -> u64 {
339 fn hash<T: std::hash::Hash + std::fmt::Debug>(x: T) -> u64 {
340 use std::{collections::hash_map::DefaultHasher, hash::Hasher};
342 let mut hasher = DefaultHasher::new();
347 hash((name, shadow_count))
351 sema: &Semantics<RootDatabase>,
352 krate: Option<hir::Crate>,
356 let mut h = match def {
357 Definition::Macro(m) => Highlight::new(HlTag::Symbol(m.kind().into())),
358 Definition::Field(_) => Highlight::new(HlTag::Symbol(SymbolKind::Field)),
359 Definition::Module(module) => {
360 let mut h = Highlight::new(HlTag::Symbol(SymbolKind::Module));
361 if module.parent(db).is_none() {
362 h |= HlMod::CrateRoot
366 Definition::Function(func) => {
367 let mut h = Highlight::new(HlTag::Symbol(SymbolKind::Function));
368 if let Some(item) = func.as_assoc_item(db) {
369 h |= HlMod::Associated;
370 match func.self_param(db) {
371 Some(sp) => match sp.access(db) {
372 hir::Access::Exclusive => {
374 h |= HlMod::Reference;
376 hir::Access::Shared => h |= HlMod::Reference,
377 hir::Access::Owned => h |= HlMod::Consuming,
379 None => h |= HlMod::Static,
382 match item.container(db) {
383 hir::AssocItemContainer::Impl(i) => {
384 if i.trait_(db).is_some() {
388 hir::AssocItemContainer::Trait(_t) => {
394 if func.is_unsafe(db) {
397 if func.is_async(db) {
403 Definition::Adt(adt) => {
405 hir::Adt::Struct(_) => HlTag::Symbol(SymbolKind::Struct),
406 hir::Adt::Enum(_) => HlTag::Symbol(SymbolKind::Enum),
407 hir::Adt::Union(_) => HlTag::Symbol(SymbolKind::Union),
412 Definition::Variant(_) => Highlight::new(HlTag::Symbol(SymbolKind::Variant)),
413 Definition::Const(konst) => {
414 let mut h = Highlight::new(HlTag::Symbol(SymbolKind::Const));
416 if let Some(item) = konst.as_assoc_item(db) {
417 h |= HlMod::Associated;
418 match item.container(db) {
419 hir::AssocItemContainer::Impl(i) => {
420 if i.trait_(db).is_some() {
424 hir::AssocItemContainer::Trait(_t) => {
432 Definition::Trait(_) => Highlight::new(HlTag::Symbol(SymbolKind::Trait)),
433 Definition::TypeAlias(type_) => {
434 let mut h = Highlight::new(HlTag::Symbol(SymbolKind::TypeAlias));
436 if let Some(item) = type_.as_assoc_item(db) {
437 h |= HlMod::Associated;
438 match item.container(db) {
439 hir::AssocItemContainer::Impl(i) => {
440 if i.trait_(db).is_some() {
444 hir::AssocItemContainer::Trait(_t) => {
452 Definition::BuiltinType(_) => Highlight::new(HlTag::BuiltinType),
453 Definition::Static(s) => {
454 let mut h = Highlight::new(HlTag::Symbol(SymbolKind::Static));
463 Definition::SelfType(_) => Highlight::new(HlTag::Symbol(SymbolKind::Impl)),
464 Definition::GenericParam(it) => match it {
465 hir::GenericParam::TypeParam(_) => Highlight::new(HlTag::Symbol(SymbolKind::TypeParam)),
466 hir::GenericParam::ConstParam(_) => {
467 Highlight::new(HlTag::Symbol(SymbolKind::ConstParam))
469 hir::GenericParam::LifetimeParam(_) => {
470 Highlight::new(HlTag::Symbol(SymbolKind::LifetimeParam))
473 Definition::Local(local) => {
474 let tag = if local.is_self(db) {
475 HlTag::Symbol(SymbolKind::SelfParam)
476 } else if local.is_param(db) {
477 HlTag::Symbol(SymbolKind::ValueParam)
479 HlTag::Symbol(SymbolKind::Local)
481 let mut h = Highlight::new(tag);
482 let ty = local.ty(db);
483 if local.is_mut(db) || ty.is_mutable_reference() {
486 if local.is_ref(db) || ty.is_reference() {
487 h |= HlMod::Reference;
489 if ty.as_callable(db).is_some() || ty.impls_fnonce(db) {
490 h |= HlMod::Callable;
494 Definition::Label(_) => Highlight::new(HlTag::Symbol(SymbolKind::Label)),
495 Definition::BuiltinAttr(_) => Highlight::new(HlTag::Symbol(SymbolKind::BuiltinAttr)),
496 Definition::ToolModule(_) => Highlight::new(HlTag::Symbol(SymbolKind::ToolModule)),
499 let famous_defs = FamousDefs(sema, krate);
500 let def_crate = def.module(db).map(hir::Module::krate).or_else(|| match def {
501 Definition::Module(module) => Some(module.krate()),
504 let is_from_other_crate = def_crate != krate;
505 let is_from_builtin_crate =
506 def_crate.map_or(false, |def_crate| famous_defs.builtin_crates().any(|it| def_crate == it));
507 let is_builtin_type = matches!(def, Definition::BuiltinType(_));
508 let is_public = def.visibility(db) == Some(hir::Visibility::Public);
510 match (is_from_other_crate, is_builtin_type, is_public) {
511 (true, false, _) => h |= HlMod::Library,
512 (false, _, true) => h |= HlMod::Public,
516 if is_from_builtin_crate {
517 h |= HlMod::DefaultLibrary;
523 fn highlight_method_call_by_name_ref(
524 sema: &Semantics<RootDatabase>,
525 krate: Option<hir::Crate>,
526 name_ref: &ast::NameRef,
527 ) -> Option<Highlight> {
528 let mc = name_ref.syntax().parent().and_then(ast::MethodCallExpr::cast)?;
529 highlight_method_call(sema, krate, &mc)
532 fn highlight_method_call(
533 sema: &Semantics<RootDatabase>,
534 krate: Option<hir::Crate>,
535 method_call: &ast::MethodCallExpr,
536 ) -> Option<Highlight> {
537 let func = sema.resolve_method_call(method_call)?;
539 let mut h = SymbolKind::Function.into();
540 h |= HlMod::Associated;
542 if func.is_unsafe(sema.db) || sema.is_unsafe_method_call(method_call) {
545 if func.is_async(sema.db) {
548 if func.as_assoc_item(sema.db).and_then(|it| it.containing_trait(sema.db)).is_some() {
552 let famous_defs = FamousDefs(sema, krate);
553 let def_crate = func.module(sema.db).krate();
554 let is_from_other_crate = Some(def_crate) != krate;
555 let is_from_builtin_crate = famous_defs.builtin_crates().any(|it| def_crate == it);
556 let is_public = func.visibility(sema.db) == hir::Visibility::Public;
558 if is_from_other_crate {
560 } else if is_public {
564 if is_from_builtin_crate {
565 h |= HlMod::DefaultLibrary;
568 if let Some(self_param) = func.self_param(sema.db) {
569 match self_param.access(sema.db) {
570 hir::Access::Shared => h |= HlMod::Reference,
571 hir::Access::Exclusive => {
573 h |= HlMod::Reference;
575 hir::Access::Owned => {
576 if let Some(receiver_ty) =
577 method_call.receiver().and_then(|it| sema.type_of_expr(&it))
579 if !receiver_ty.adjusted().is_copy(sema.db) {
580 h |= HlMod::Consuming
589 fn highlight_name_by_syntax(name: ast::Name) -> Highlight {
590 let default = HlTag::UnresolvedReference;
592 let parent = match name.syntax().parent() {
594 _ => return default.into(),
597 let tag = match parent.kind() {
598 STRUCT => SymbolKind::Struct,
599 ENUM => SymbolKind::Enum,
600 VARIANT => SymbolKind::Variant,
601 UNION => SymbolKind::Union,
602 TRAIT => SymbolKind::Trait,
603 TYPE_ALIAS => SymbolKind::TypeAlias,
604 TYPE_PARAM => SymbolKind::TypeParam,
605 RECORD_FIELD => SymbolKind::Field,
606 MODULE => SymbolKind::Module,
607 FN => SymbolKind::Function,
608 CONST => SymbolKind::Const,
609 STATIC => SymbolKind::Static,
610 IDENT_PAT => SymbolKind::Local,
611 _ => return default.into(),
617 fn highlight_name_ref_by_syntax(
619 sema: &Semantics<RootDatabase>,
620 krate: Option<hir::Crate>,
622 let default = HlTag::UnresolvedReference;
624 let parent = match name.syntax().parent() {
626 _ => return default.into(),
629 match parent.kind() {
630 METHOD_CALL_EXPR => ast::MethodCallExpr::cast(parent)
631 .and_then(|it| highlight_method_call(sema, krate, &it))
632 .unwrap_or_else(|| SymbolKind::Function.into()),
634 let h = HlTag::Symbol(SymbolKind::Field);
635 let is_union = ast::FieldExpr::cast(parent)
636 .and_then(|field_expr| sema.resolve_field(&field_expr))
637 .map_or(false, |field| {
638 matches!(field.parent_def(sema.db), hir::VariantDef::Union(_))
647 let name_based_fallback = || {
648 if name.text().chars().next().unwrap_or_default().is_uppercase() {
649 SymbolKind::Struct.into()
651 SymbolKind::Module.into()
654 let path = match parent.parent().and_then(ast::Path::cast) {
656 _ => return name_based_fallback(),
658 let expr = match path.syntax().parent() {
659 Some(parent) => match_ast! {
661 ast::PathExpr(path) => path,
662 ast::MacroCall(_) => return SymbolKind::Macro.into(),
663 _ => return name_based_fallback(),
666 // within path, decide whether it is module or adt by checking for uppercase name
667 None => return name_based_fallback(),
669 let parent = match expr.syntax().parent() {
671 None => return default.into(),
674 match parent.kind() {
675 CALL_EXPR => SymbolKind::Function.into(),
676 _ => if name.text().chars().next().unwrap_or_default().is_uppercase() {
688 fn is_consumed_lvalue(node: &SyntaxNode, local: &hir::Local, db: &RootDatabase) -> bool {
689 // When lvalues are passed as arguments and they're not Copy, then mark them as Consuming.
690 parents_match(node.clone().into(), &[PATH_SEGMENT, PATH, PATH_EXPR, ARG_LIST])
691 && !local.ty(db).is_copy(db)
694 /// Returns true if the parent nodes of `node` all match the `SyntaxKind`s in `kinds` exactly.
695 fn parents_match(mut node: NodeOrToken<SyntaxNode, SyntaxToken>, mut kinds: &[SyntaxKind]) -> bool {
696 while let (Some(parent), [kind, rest @ ..]) = (&node.parent(), kinds) {
697 if parent.kind() != *kind {
701 // FIXME: Would be nice to get parent out of the match, but binding by-move and by-value
702 // in the same pattern is unstable: rust-lang/rust#68354.
703 node = node.parent().unwrap().into();
707 // Only true if we matched all expected kinds
711 fn parent_matches<N: AstNode>(token: &SyntaxToken) -> bool {
712 token.parent().map_or(false, |it| N::can_cast(it.kind()))
715 fn is_in_fn_with_self_param(node: &ast::NameRef) -> bool {
718 .find_map(ast::Item::cast)
719 .and_then(|item| match item {
720 ast::Item::Fn(fn_) => fn_.param_list()?.self_param(),