1 //! Computes color for a single element.
3 use hir::{AsAssocItem, HasVisibility, Semantics};
5 defs::{Definition, IdentClass, NameClass, NameRefClass},
6 FxHashMap, RootDatabase, SymbolKind,
9 ast, match_ast, AstNode, AstToken, NodeOrToken,
10 SyntaxKind::{self, *},
11 SyntaxNode, SyntaxToken, T,
15 syntax_highlighting::tags::{HlOperator, HlPunct},
16 Highlight, HlMod, HlTag,
19 pub(super) fn token(sema: &Semantics<RootDatabase>, token: SyntaxToken) -> Option<Highlight> {
20 if let Some(comment) = ast::Comment::cast(token.clone()) {
21 let h = HlTag::Comment;
22 return Some(match comment.kind().doc {
23 Some(_) => h | HlMod::Documentation,
28 let highlight: Highlight = match token.kind() {
29 STRING | BYTE_STRING => HlTag::StringLiteral.into(),
30 INT_NUMBER if token.parent_ancestors().nth(1).map(|it| it.kind()) == Some(FIELD_EXPR) => {
31 SymbolKind::Field.into()
33 INT_NUMBER | FLOAT_NUMBER => HlTag::NumericLiteral.into(),
34 BYTE => HlTag::ByteLiteral.into(),
35 CHAR => HlTag::CharLiteral.into(),
36 IDENT if token.parent().and_then(ast::TokenTree::cast).is_some() => {
37 // from this point on we are inside a token tree, this only happens for identifiers
38 // that were not mapped down into macro invocations
41 p if p.is_punct() => punctuation(sema, token, p),
42 k if k.is_keyword() => keyword(sema, token, k)?,
48 pub(super) fn name_like(
49 sema: &Semantics<RootDatabase>,
51 bindings_shadow_count: &mut FxHashMap<hir::Name, u32>,
52 syntactic_name_ref_highlighting: bool,
53 name_like: ast::NameLike,
54 ) -> Option<(Highlight, Option<u64>)> {
55 let mut binding_hash = None;
56 let highlight = match name_like {
57 ast::NameLike::NameRef(name_ref) => highlight_name_ref(
60 bindings_shadow_count,
62 syntactic_name_ref_highlighting,
65 ast::NameLike::Name(name) => {
66 highlight_name(sema, bindings_shadow_count, &mut binding_hash, krate, name)
68 ast::NameLike::Lifetime(lifetime) => match IdentClass::classify_lifetime(sema, &lifetime) {
69 Some(IdentClass::NameClass(NameClass::Definition(def))) => {
70 highlight_def(sema, krate, def) | HlMod::Definition
72 Some(IdentClass::NameRefClass(NameRefClass::Definition(def))) => {
73 highlight_def(sema, krate, def)
75 // FIXME: Fallback for 'static and '_, as we do not resolve these yet
76 _ => SymbolKind::LifetimeParam.into(),
79 Some((highlight, binding_hash))
82 fn punctuation(sema: &Semantics<RootDatabase>, token: SyntaxToken, kind: SyntaxKind) -> Highlight {
83 let parent = token.parent();
84 let parent_kind = parent.as_ref().map_or(EOF, SyntaxNode::kind);
85 match (kind, parent_kind) {
86 (T![?], _) => HlTag::Operator(HlOperator::Other) | HlMod::ControlFlow,
87 (T![&], BIN_EXPR) => HlOperator::Bitwise.into(),
89 let h = HlTag::Operator(HlOperator::Other).into();
90 let is_unsafe = parent
91 .and_then(ast::RefExpr::cast)
92 .map(|ref_expr| sema.is_unsafe_ref_expr(&ref_expr));
93 if let Some(true) = is_unsafe {
99 (T![::] | T![->] | T![=>] | T![..] | T![=] | T![@] | T![.], _) => HlOperator::Other.into(),
100 (T![!], MACRO_CALL | MACRO_RULES) => HlPunct::MacroBang.into(),
101 (T![!], NEVER_TYPE) => HlTag::BuiltinType.into(),
102 (T![!], PREFIX_EXPR) => HlOperator::Logical.into(),
103 (T![*], PTR_TYPE) => HlTag::Keyword.into(),
104 (T![*], PREFIX_EXPR) => {
105 let is_raw_ptr = (|| {
106 let prefix_expr = parent.and_then(ast::PrefixExpr::cast)?;
107 let expr = prefix_expr.expr()?;
108 sema.type_of_expr(&expr)?.original.is_raw_ptr().then(|| ())
110 if let Some(()) = is_raw_ptr {
111 HlTag::Operator(HlOperator::Other) | HlMod::Unsafe
113 HlOperator::Other.into()
116 (T![-], PREFIX_EXPR) => {
117 let prefix_expr = parent.and_then(ast::PrefixExpr::cast).and_then(|e| e.expr());
119 Some(ast::Expr::Literal(_)) => HlTag::NumericLiteral,
120 _ => HlTag::Operator(HlOperator::Other),
124 (T![+] | T![-] | T![*] | T![/] | T![%], BIN_EXPR) => HlOperator::Arithmetic.into(),
125 (T![+=] | T![-=] | T![*=] | T![/=] | T![%=], BIN_EXPR) => {
126 Highlight::from(HlOperator::Arithmetic) | HlMod::Mutable
128 (T![|] | T![&] | T![!] | T![^] | T![>>] | T![<<], BIN_EXPR) => HlOperator::Bitwise.into(),
129 (T![|=] | T![&=] | T![^=] | T![>>=] | T![<<=], BIN_EXPR) => {
130 Highlight::from(HlOperator::Bitwise) | HlMod::Mutable
132 (T![&&] | T![||], BIN_EXPR) => HlOperator::Logical.into(),
133 (T![>] | T![<] | T![==] | T![>=] | T![<=] | T![!=], BIN_EXPR) => {
134 HlOperator::Comparison.into()
136 (_, PREFIX_EXPR | BIN_EXPR | RANGE_EXPR | RANGE_PAT | REST_PAT) => HlOperator::Other.into(),
137 (_, ATTR) => HlTag::AttributeBracket.into(),
138 (kind, _) => match kind {
139 T!['['] | T![']'] => HlPunct::Bracket,
140 T!['{'] | T!['}'] => HlPunct::Brace,
141 T!['('] | T![')'] => HlPunct::Parenthesis,
142 T![<] | T![>] => HlPunct::Angle,
143 T![,] => HlPunct::Comma,
144 T![:] => HlPunct::Colon,
145 T![;] => HlPunct::Semi,
146 T![.] => HlPunct::Dot,
154 sema: &Semantics<RootDatabase>,
157 ) -> Option<Highlight> {
158 let h = Highlight::new(HlTag::Keyword);
160 T![await] => h | HlMod::Async | HlMod::ControlFlow,
161 T![async] => h | HlMod::Async,
171 | T![yield] => h | HlMod::ControlFlow,
172 T![for] if parent_matches::<ast::ForExpr>(&token) => h | HlMod::ControlFlow,
173 T![unsafe] => h | HlMod::Unsafe,
174 T![true] | T![false] => HlTag::BoolLiteral.into(),
175 // crate is handled just as a token if it's in an `extern crate`
176 T![crate] if parent_matches::<ast::ExternCrate>(&token) => h,
177 // self, crate, super and `Self` are handled as either a Name or NameRef already, unless they
178 // are inside unmapped token trees
179 T![self] | T![crate] | T![super] | T![Self] if parent_matches::<ast::NameRef>(&token) => {
182 T![self] if parent_matches::<ast::Name>(&token) => return None,
183 T![ref] => match token.parent().and_then(ast::IdentPat::cast) {
184 Some(ident) if sema.is_unsafe_ident_pat(&ident) => h | HlMod::Unsafe,
192 fn highlight_name_ref(
193 sema: &Semantics<RootDatabase>,
195 bindings_shadow_count: &mut FxHashMap<hir::Name, u32>,
196 binding_hash: &mut Option<u64>,
197 syntactic_name_ref_highlighting: bool,
198 name_ref: ast::NameRef,
201 if let Some(res) = highlight_method_call_by_name_ref(sema, krate, &name_ref) {
205 let name_class = match NameRefClass::classify(sema, &name_ref) {
206 Some(name_kind) => name_kind,
207 None if syntactic_name_ref_highlighting => {
208 return highlight_name_ref_by_syntax(name_ref, sema, krate)
210 // FIXME: This is required for helper attributes used by proc-macros, as those do not map down
211 // to anything when used.
212 // We can fix this for derive attributes since derive helpers are recorded, but not for
213 // general attributes.
214 None if name_ref.syntax().ancestors().any(|it| it.kind() == ATTR) => {
215 return HlTag::Symbol(SymbolKind::Attribute).into();
217 None => return HlTag::UnresolvedReference.into(),
219 let mut h = match name_class {
220 NameRefClass::Definition(def) => {
221 if let Definition::Local(local) = &def {
222 let name = local.name(db);
223 let shadow_count = bindings_shadow_count.entry(name.clone()).or_default();
224 *binding_hash = Some(calc_binding_hash(&name, *shadow_count))
227 let mut h = highlight_def(sema, krate, def);
230 Definition::Local(local) if is_consumed_lvalue(name_ref.syntax(), &local, db) => {
231 h |= HlMod::Consuming;
233 Definition::Trait(trait_) if trait_.is_unsafe(db) => {
234 if ast::Impl::for_trait_name_ref(&name_ref)
235 .map_or(false, |impl_| impl_.unsafe_token().is_some())
240 Definition::Field(field) => {
241 if let Some(parent) = name_ref.syntax().parent() {
242 if matches!(parent.kind(), FIELD_EXPR | RECORD_PAT_FIELD) {
243 if let hir::VariantDef::Union(_) = field.parent_def(db) {
249 Definition::Macro(_) => {
250 if let Some(macro_call) =
251 ide_db::syntax_helpers::node_ext::full_path_of_name_ref(&name_ref)
252 .and_then(|it| it.syntax().parent().and_then(ast::MacroCall::cast))
254 if sema.is_unsafe_macro_call(¯o_call) {
264 NameRefClass::FieldShorthand { .. } => SymbolKind::Field.into(),
267 h.tag = match name_ref.token_kind() {
268 T![Self] => HlTag::Symbol(SymbolKind::SelfType),
269 T![self] => HlTag::Symbol(SymbolKind::SelfParam),
270 T![super] | T![crate] => HlTag::Keyword,
277 sema: &Semantics<RootDatabase>,
278 bindings_shadow_count: &mut FxHashMap<hir::Name, u32>,
279 binding_hash: &mut Option<u64>,
283 let name_kind = NameClass::classify(sema, &name);
284 if let Some(NameClass::Definition(Definition::Local(local))) = &name_kind {
285 let name = local.name(sema.db);
286 let shadow_count = bindings_shadow_count.entry(name.clone()).or_default();
288 *binding_hash = Some(calc_binding_hash(&name, *shadow_count))
291 Some(NameClass::Definition(def)) => {
292 let mut h = highlight_def(sema, krate, def) | HlMod::Definition;
293 if let Definition::Trait(trait_) = &def {
294 if trait_.is_unsafe(sema.db) {
300 Some(NameClass::ConstReference(def)) => highlight_def(sema, krate, def),
301 Some(NameClass::PatFieldShorthand { field_ref, .. }) => {
302 let mut h = HlTag::Symbol(SymbolKind::Field).into();
303 if let hir::VariantDef::Union(_) = field_ref.parent_def(sema.db) {
308 None => highlight_name_by_syntax(name) | HlMod::Definition,
312 fn calc_binding_hash(name: &hir::Name, shadow_count: u32) -> u64 {
313 fn hash<T: std::hash::Hash + std::fmt::Debug>(x: T) -> u64 {
314 use std::{collections::hash_map::DefaultHasher, hash::Hasher};
316 let mut hasher = DefaultHasher::new();
321 hash((name, shadow_count))
324 fn highlight_def(sema: &Semantics<RootDatabase>, krate: hir::Crate, def: Definition) -> Highlight {
326 let mut h = match def {
327 Definition::Macro(m) => Highlight::new(HlTag::Symbol(m.kind(sema.db).into())),
328 Definition::Field(_) => Highlight::new(HlTag::Symbol(SymbolKind::Field)),
329 Definition::Module(module) => {
330 let mut h = Highlight::new(HlTag::Symbol(SymbolKind::Module));
331 if module.parent(db).is_none() {
332 h |= HlMod::CrateRoot
336 Definition::Function(func) => {
337 let mut h = Highlight::new(HlTag::Symbol(SymbolKind::Function));
338 if let Some(item) = func.as_assoc_item(db) {
339 h |= HlMod::Associated;
340 match func.self_param(db) {
341 Some(sp) => match sp.access(db) {
342 hir::Access::Exclusive => {
344 h |= HlMod::Reference;
346 hir::Access::Shared => h |= HlMod::Reference,
347 hir::Access::Owned => h |= HlMod::Consuming,
349 None => h |= HlMod::Static,
352 match item.container(db) {
353 hir::AssocItemContainer::Impl(i) => {
354 if i.trait_(db).is_some() {
358 hir::AssocItemContainer::Trait(_t) => {
364 if func.is_unsafe_to_call(db) {
367 if func.is_async(db) {
373 Definition::Adt(adt) => {
375 hir::Adt::Struct(_) => HlTag::Symbol(SymbolKind::Struct),
376 hir::Adt::Enum(_) => HlTag::Symbol(SymbolKind::Enum),
377 hir::Adt::Union(_) => HlTag::Symbol(SymbolKind::Union),
382 Definition::Variant(_) => Highlight::new(HlTag::Symbol(SymbolKind::Variant)),
383 Definition::Const(konst) => {
384 let mut h = Highlight::new(HlTag::Symbol(SymbolKind::Const));
386 if let Some(item) = konst.as_assoc_item(db) {
387 h |= HlMod::Associated;
388 match item.container(db) {
389 hir::AssocItemContainer::Impl(i) => {
390 if i.trait_(db).is_some() {
394 hir::AssocItemContainer::Trait(_t) => {
402 Definition::Trait(_) => Highlight::new(HlTag::Symbol(SymbolKind::Trait)),
403 Definition::TypeAlias(type_) => {
404 let mut h = Highlight::new(HlTag::Symbol(SymbolKind::TypeAlias));
406 if let Some(item) = type_.as_assoc_item(db) {
407 h |= HlMod::Associated;
408 match item.container(db) {
409 hir::AssocItemContainer::Impl(i) => {
410 if i.trait_(db).is_some() {
414 hir::AssocItemContainer::Trait(_t) => {
422 Definition::BuiltinType(_) => Highlight::new(HlTag::BuiltinType),
423 Definition::Static(s) => {
424 let mut h = Highlight::new(HlTag::Symbol(SymbolKind::Static));
433 Definition::SelfType(_) => Highlight::new(HlTag::Symbol(SymbolKind::Impl)),
434 Definition::GenericParam(it) => match it {
435 hir::GenericParam::TypeParam(_) => Highlight::new(HlTag::Symbol(SymbolKind::TypeParam)),
436 hir::GenericParam::ConstParam(_) => {
437 Highlight::new(HlTag::Symbol(SymbolKind::ConstParam))
439 hir::GenericParam::LifetimeParam(_) => {
440 Highlight::new(HlTag::Symbol(SymbolKind::LifetimeParam))
443 Definition::Local(local) => {
444 let tag = if local.is_self(db) {
445 HlTag::Symbol(SymbolKind::SelfParam)
446 } else if local.is_param(db) {
447 HlTag::Symbol(SymbolKind::ValueParam)
449 HlTag::Symbol(SymbolKind::Local)
451 let mut h = Highlight::new(tag);
452 let ty = local.ty(db);
453 if local.is_mut(db) || ty.is_mutable_reference() {
456 if local.is_ref(db) || ty.is_reference() {
457 h |= HlMod::Reference;
459 if ty.as_callable(db).is_some() || ty.impls_fnonce(db) {
460 h |= HlMod::Callable;
464 Definition::Label(_) => Highlight::new(HlTag::Symbol(SymbolKind::Label)),
465 Definition::BuiltinAttr(_) => Highlight::new(HlTag::Symbol(SymbolKind::BuiltinAttr)),
466 Definition::ToolModule(_) => Highlight::new(HlTag::Symbol(SymbolKind::ToolModule)),
469 let def_crate = def.krate(db);
470 let is_from_other_crate = def_crate != Some(krate);
471 let is_from_builtin_crate = def_crate.map_or(false, |def_crate| def_crate.is_builtin(db));
472 let is_builtin_type = matches!(def, Definition::BuiltinType(_));
473 let is_public = def.visibility(db) == Some(hir::Visibility::Public);
475 match (is_from_other_crate, is_builtin_type, is_public) {
476 (true, false, _) => h |= HlMod::Library,
477 (false, _, true) => h |= HlMod::Public,
481 if is_from_builtin_crate {
482 h |= HlMod::DefaultLibrary;
488 fn highlight_method_call_by_name_ref(
489 sema: &Semantics<RootDatabase>,
491 name_ref: &ast::NameRef,
492 ) -> Option<Highlight> {
493 let mc = name_ref.syntax().parent().and_then(ast::MethodCallExpr::cast)?;
494 highlight_method_call(sema, krate, &mc)
497 fn highlight_method_call(
498 sema: &Semantics<RootDatabase>,
500 method_call: &ast::MethodCallExpr,
501 ) -> Option<Highlight> {
502 let func = sema.resolve_method_call(method_call)?;
504 let mut h = SymbolKind::Function.into();
505 h |= HlMod::Associated;
507 if func.is_unsafe_to_call(sema.db) || sema.is_unsafe_method_call(method_call) {
510 if func.is_async(sema.db) {
513 if func.as_assoc_item(sema.db).and_then(|it| it.containing_trait(sema.db)).is_some() {
517 let def_crate = func.module(sema.db).krate();
518 let is_from_other_crate = def_crate != krate;
519 let is_from_builtin_crate = def_crate.is_builtin(sema.db);
520 let is_public = func.visibility(sema.db) == hir::Visibility::Public;
522 if is_from_other_crate {
524 } else if is_public {
528 if is_from_builtin_crate {
529 h |= HlMod::DefaultLibrary;
532 if let Some(self_param) = func.self_param(sema.db) {
533 match self_param.access(sema.db) {
534 hir::Access::Shared => h |= HlMod::Reference,
535 hir::Access::Exclusive => {
537 h |= HlMod::Reference;
539 hir::Access::Owned => {
540 if let Some(receiver_ty) =
541 method_call.receiver().and_then(|it| sema.type_of_expr(&it))
543 if !receiver_ty.adjusted().is_copy(sema.db) {
544 h |= HlMod::Consuming
553 fn highlight_name_by_syntax(name: ast::Name) -> Highlight {
554 let default = HlTag::UnresolvedReference;
556 let parent = match name.syntax().parent() {
558 _ => return default.into(),
561 let tag = match parent.kind() {
562 STRUCT => SymbolKind::Struct,
563 ENUM => SymbolKind::Enum,
564 VARIANT => SymbolKind::Variant,
565 UNION => SymbolKind::Union,
566 TRAIT => SymbolKind::Trait,
567 TYPE_ALIAS => SymbolKind::TypeAlias,
568 TYPE_PARAM => SymbolKind::TypeParam,
569 RECORD_FIELD => SymbolKind::Field,
570 MODULE => SymbolKind::Module,
571 FN => SymbolKind::Function,
572 CONST => SymbolKind::Const,
573 STATIC => SymbolKind::Static,
574 IDENT_PAT => SymbolKind::Local,
575 _ => return default.into(),
581 fn highlight_name_ref_by_syntax(
583 sema: &Semantics<RootDatabase>,
586 let default = HlTag::UnresolvedReference;
588 let parent = match name.syntax().parent() {
590 _ => return default.into(),
593 match parent.kind() {
594 METHOD_CALL_EXPR => ast::MethodCallExpr::cast(parent)
595 .and_then(|it| highlight_method_call(sema, krate, &it))
596 .unwrap_or_else(|| SymbolKind::Function.into()),
598 let h = HlTag::Symbol(SymbolKind::Field);
599 let is_union = ast::FieldExpr::cast(parent)
600 .and_then(|field_expr| sema.resolve_field(&field_expr))
601 .map_or(false, |field| {
602 matches!(field.parent_def(sema.db), hir::VariantDef::Union(_))
611 let name_based_fallback = || {
612 if name.text().chars().next().unwrap_or_default().is_uppercase() {
613 SymbolKind::Struct.into()
615 SymbolKind::Module.into()
618 let path = match parent.parent().and_then(ast::Path::cast) {
620 _ => return name_based_fallback(),
622 let expr = match path.syntax().parent() {
623 Some(parent) => match_ast! {
625 ast::PathExpr(path) => path,
626 ast::MacroCall(_) => return SymbolKind::Macro.into(),
627 _ => return name_based_fallback(),
630 // within path, decide whether it is module or adt by checking for uppercase name
631 None => return name_based_fallback(),
633 let parent = match expr.syntax().parent() {
635 None => return default.into(),
638 match parent.kind() {
639 CALL_EXPR => SymbolKind::Function.into(),
640 _ => if name.text().chars().next().unwrap_or_default().is_uppercase() {
652 fn is_consumed_lvalue(node: &SyntaxNode, local: &hir::Local, db: &RootDatabase) -> bool {
653 // When lvalues are passed as arguments and they're not Copy, then mark them as Consuming.
654 parents_match(node.clone().into(), &[PATH_SEGMENT, PATH, PATH_EXPR, ARG_LIST])
655 && !local.ty(db).is_copy(db)
658 /// Returns true if the parent nodes of `node` all match the `SyntaxKind`s in `kinds` exactly.
659 fn parents_match(mut node: NodeOrToken<SyntaxNode, SyntaxToken>, mut kinds: &[SyntaxKind]) -> bool {
660 while let (Some(parent), [kind, rest @ ..]) = (&node.parent(), kinds) {
661 if parent.kind() != *kind {
665 // FIXME: Would be nice to get parent out of the match, but binding by-move and by-value
666 // in the same pattern is unstable: rust-lang/rust#68354.
667 node = node.parent().unwrap().into();
671 // Only true if we matched all expected kinds
675 fn parent_matches<N: AstNode>(token: &SyntaxToken) -> bool {
676 token.parent().map_or(false, |it| N::can_cast(it.kind()))