1 //! Computes color for a single element.
3 use hir::{AsAssocItem, HasVisibility, Semantics};
5 defs::{Definition, IdentClass, NameClass, NameRefClass},
6 famous_defs::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,
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)?,
50 pub(super) fn name_like(
51 sema: &Semantics<RootDatabase>,
52 krate: Option<hir::Crate>,
53 bindings_shadow_count: &mut FxHashMap<hir::Name, u32>,
54 syntactic_name_ref_highlighting: bool,
55 name_like: ast::NameLike,
56 ) -> Option<(Highlight, Option<u64>)> {
57 let mut binding_hash = None;
58 let highlight = match name_like {
59 ast::NameLike::NameRef(name_ref) => highlight_name_ref(
62 bindings_shadow_count,
64 syntactic_name_ref_highlighting,
67 ast::NameLike::Name(name) => {
68 highlight_name(sema, bindings_shadow_count, &mut binding_hash, krate, name)
70 ast::NameLike::Lifetime(lifetime) => match IdentClass::classify_lifetime(sema, &lifetime) {
71 Some(IdentClass::NameClass(NameClass::Definition(def))) => {
72 highlight_def(sema, krate, def) | HlMod::Definition
74 Some(IdentClass::NameRefClass(NameRefClass::Definition(def))) => {
75 highlight_def(sema, krate, def)
77 // FIXME: Fallback for 'static and '_, as we do not resolve these yet
78 _ => SymbolKind::LifetimeParam.into(),
81 Some((highlight, binding_hash))
84 fn punctuation(sema: &Semantics<RootDatabase>, token: SyntaxToken, kind: SyntaxKind) -> Highlight {
85 let parent = token.parent();
86 let parent_kind = parent.as_ref().map_or(EOF, SyntaxNode::kind);
87 match (kind, parent_kind) {
88 (T![?], _) => HlTag::Operator(HlOperator::Other) | HlMod::ControlFlow,
89 (T![&], BIN_EXPR) => HlOperator::Bitwise.into(),
91 let h = HlTag::Operator(HlOperator::Other).into();
92 let is_unsafe = parent
93 .and_then(ast::RefExpr::cast)
94 .map(|ref_expr| sema.is_unsafe_ref_expr(&ref_expr));
95 if let Some(true) = is_unsafe {
101 (T![::] | T![->] | T![=>] | T![..] | T![=] | T![@] | T![.], _) => HlOperator::Other.into(),
102 (T![!], MACRO_CALL) => HlPunct::MacroBang.into(),
103 (T![!], NEVER_TYPE) => HlTag::BuiltinType.into(),
104 (T![!], PREFIX_EXPR) => HlOperator::Logical.into(),
105 (T![*], PTR_TYPE) => HlTag::Keyword.into(),
106 (T![*], PREFIX_EXPR) => {
107 let is_raw_ptr = (|| {
108 let prefix_expr = parent.and_then(ast::PrefixExpr::cast)?;
109 let expr = prefix_expr.expr()?;
110 sema.type_of_expr(&expr)?.original.is_raw_ptr().then(|| ())
112 if let Some(()) = is_raw_ptr {
113 HlTag::Operator(HlOperator::Other) | HlMod::Unsafe
115 HlOperator::Other.into()
118 (T![-], PREFIX_EXPR) => {
119 let prefix_expr = parent.and_then(ast::PrefixExpr::cast).and_then(|e| e.expr());
121 Some(ast::Expr::Literal(_)) => HlTag::NumericLiteral,
122 _ => HlTag::Operator(HlOperator::Other),
126 (T![+] | T![-] | T![*] | T![/] | T![%], BIN_EXPR) => HlOperator::Arithmetic.into(),
127 (T![+=] | T![-=] | T![*=] | T![/=] | T![%=], BIN_EXPR) => {
128 Highlight::from(HlOperator::Arithmetic) | HlMod::Mutable
130 (T![|] | T![&] | T![!] | T![^] | T![>>] | T![<<], BIN_EXPR) => HlOperator::Bitwise.into(),
131 (T![|=] | T![&=] | T![^=] | T![>>=] | T![<<=], BIN_EXPR) => {
132 Highlight::from(HlOperator::Bitwise) | HlMod::Mutable
134 (T![&&] | T![||], BIN_EXPR) => HlOperator::Logical.into(),
135 (T![>] | T![<] | T![==] | T![>=] | T![<=] | T![!=], BIN_EXPR) => {
136 HlOperator::Comparison.into()
138 (_, PREFIX_EXPR | BIN_EXPR | RANGE_EXPR | RANGE_PAT | REST_PAT) => HlOperator::Other.into(),
139 (_, ATTR) => HlTag::AttributeBracket.into(),
140 (kind, _) => match kind {
141 T!['['] | T![']'] => HlPunct::Bracket,
142 T!['{'] | T!['}'] => HlPunct::Brace,
143 T!['('] | T![')'] => HlPunct::Parenthesis,
144 T![<] | T![>] => HlPunct::Angle,
145 T![,] => HlPunct::Comma,
146 T![:] => HlPunct::Colon,
147 T![;] => HlPunct::Semi,
148 T![.] => HlPunct::Dot,
156 sema: &Semantics<RootDatabase>,
159 ) -> Option<Highlight> {
160 let h = Highlight::new(HlTag::Keyword);
162 T![await] => h | HlMod::Async | HlMod::ControlFlow,
163 T![async] => h | HlMod::Async,
173 | T![yield] => h | HlMod::ControlFlow,
174 T![for] if parent_matches::<ast::ForExpr>(&token) => h | HlMod::ControlFlow,
175 T![unsafe] => h | HlMod::Unsafe,
176 T![true] | T![false] => HlTag::BoolLiteral.into(),
177 // crate is handled just as a token if it's in an `extern crate`
178 T![crate] if parent_matches::<ast::ExternCrate>(&token) => h,
179 // self, crate, super and `Self` are handled as either a Name or NameRef already, unless they
180 // are inside unmapped token trees
181 T![self] | T![crate] | T![super] | T![Self] if parent_matches::<ast::NameRef>(&token) => {
184 T![self] if parent_matches::<ast::Name>(&token) => return None,
185 T![ref] => match token.parent().and_then(ast::IdentPat::cast) {
186 Some(ident) if sema.is_unsafe_ident_pat(&ident) => h | HlMod::Unsafe,
194 fn highlight_name_ref(
195 sema: &Semantics<RootDatabase>,
196 krate: Option<hir::Crate>,
197 bindings_shadow_count: &mut FxHashMap<hir::Name, u32>,
198 binding_hash: &mut Option<u64>,
199 syntactic_name_ref_highlighting: bool,
200 name_ref: ast::NameRef,
203 if let Some(res) = highlight_method_call_by_name_ref(sema, krate, &name_ref) {
207 let name_class = match NameRefClass::classify(sema, &name_ref) {
208 Some(name_kind) => name_kind,
209 None if syntactic_name_ref_highlighting => {
210 return highlight_name_ref_by_syntax(name_ref, sema, krate)
212 // FIXME: This is required for helper attributes used by proc-macros, as those do not map down
213 // to anything when used.
214 // We can fix this for derive attributes since derive helpers are recorded, but not for
215 // general attributes.
216 None if name_ref.syntax().ancestors().any(|it| it.kind() == ATTR) => {
217 return HlTag::Symbol(SymbolKind::Attribute).into();
219 None => return HlTag::UnresolvedReference.into(),
221 let mut h = match name_class {
222 NameRefClass::Definition(def) => {
223 if let Definition::Local(local) = &def {
224 let name = local.name(db);
225 let shadow_count = bindings_shadow_count.entry(name.clone()).or_default();
226 *binding_hash = Some(calc_binding_hash(&name, *shadow_count))
229 let mut h = highlight_def(sema, krate, def);
232 Definition::Local(local) if is_consumed_lvalue(name_ref.syntax(), &local, db) => {
233 h |= HlMod::Consuming;
235 Definition::Trait(trait_) if trait_.is_unsafe(db) => {
236 if ast::Impl::for_trait_name_ref(&name_ref)
237 .map_or(false, |impl_| impl_.unsafe_token().is_some())
242 Definition::Field(field) => {
243 if let Some(parent) = name_ref.syntax().parent() {
244 if matches!(parent.kind(), FIELD_EXPR | RECORD_PAT_FIELD) {
245 if let hir::VariantDef::Union(_) = field.parent_def(db) {
251 Definition::Macro(_) => {
252 if let Some(macro_call) =
253 ide_db::syntax_helpers::node_ext::full_path_of_name_ref(&name_ref)
254 .and_then(|it| it.syntax().parent().and_then(ast::MacroCall::cast))
256 if sema.is_unsafe_macro_call(¯o_call) {
266 NameRefClass::FieldShorthand { .. } => SymbolKind::Field.into(),
269 h.tag = match name_ref.token_kind() {
270 T![Self] => HlTag::Symbol(SymbolKind::SelfType),
271 T![self] => HlTag::Symbol(SymbolKind::SelfParam),
272 T![super] | T![crate] => HlTag::Keyword,
279 sema: &Semantics<RootDatabase>,
280 bindings_shadow_count: &mut FxHashMap<hir::Name, u32>,
281 binding_hash: &mut Option<u64>,
282 krate: Option<hir::Crate>,
285 let name_kind = NameClass::classify(sema, &name);
286 if let Some(NameClass::Definition(Definition::Local(local))) = &name_kind {
287 let name = local.name(sema.db);
288 let shadow_count = bindings_shadow_count.entry(name.clone()).or_default();
290 *binding_hash = Some(calc_binding_hash(&name, *shadow_count))
293 Some(NameClass::Definition(def)) => {
294 let mut h = highlight_def(sema, krate, def) | HlMod::Definition;
295 if let Definition::Trait(trait_) = &def {
296 if trait_.is_unsafe(sema.db) {
302 Some(NameClass::ConstReference(def)) => highlight_def(sema, krate, def),
303 Some(NameClass::PatFieldShorthand { field_ref, .. }) => {
304 let mut h = HlTag::Symbol(SymbolKind::Field).into();
305 if let hir::VariantDef::Union(_) = field_ref.parent_def(sema.db) {
310 None => highlight_name_by_syntax(name) | HlMod::Definition,
314 fn calc_binding_hash(name: &hir::Name, shadow_count: u32) -> u64 {
315 fn hash<T: std::hash::Hash + std::fmt::Debug>(x: T) -> u64 {
316 use std::{collections::hash_map::DefaultHasher, hash::Hasher};
318 let mut hasher = DefaultHasher::new();
323 hash((name, shadow_count))
327 sema: &Semantics<RootDatabase>,
328 krate: Option<hir::Crate>,
332 let mut h = match def {
333 Definition::Macro(m) => Highlight::new(HlTag::Symbol(m.kind(sema.db).into())),
334 Definition::Field(_) => Highlight::new(HlTag::Symbol(SymbolKind::Field)),
335 Definition::Module(module) => {
336 let mut h = Highlight::new(HlTag::Symbol(SymbolKind::Module));
337 if module.parent(db).is_none() {
338 h |= HlMod::CrateRoot
342 Definition::Function(func) => {
343 let mut h = Highlight::new(HlTag::Symbol(SymbolKind::Function));
344 if let Some(item) = func.as_assoc_item(db) {
345 h |= HlMod::Associated;
346 match func.self_param(db) {
347 Some(sp) => match sp.access(db) {
348 hir::Access::Exclusive => {
350 h |= HlMod::Reference;
352 hir::Access::Shared => h |= HlMod::Reference,
353 hir::Access::Owned => h |= HlMod::Consuming,
355 None => h |= HlMod::Static,
358 match item.container(db) {
359 hir::AssocItemContainer::Impl(i) => {
360 if i.trait_(db).is_some() {
364 hir::AssocItemContainer::Trait(_t) => {
370 if func.is_unsafe(db) {
373 if func.is_async(db) {
379 Definition::Adt(adt) => {
381 hir::Adt::Struct(_) => HlTag::Symbol(SymbolKind::Struct),
382 hir::Adt::Enum(_) => HlTag::Symbol(SymbolKind::Enum),
383 hir::Adt::Union(_) => HlTag::Symbol(SymbolKind::Union),
388 Definition::Variant(_) => Highlight::new(HlTag::Symbol(SymbolKind::Variant)),
389 Definition::Const(konst) => {
390 let mut h = Highlight::new(HlTag::Symbol(SymbolKind::Const));
392 if let Some(item) = konst.as_assoc_item(db) {
393 h |= HlMod::Associated;
394 match item.container(db) {
395 hir::AssocItemContainer::Impl(i) => {
396 if i.trait_(db).is_some() {
400 hir::AssocItemContainer::Trait(_t) => {
408 Definition::Trait(_) => Highlight::new(HlTag::Symbol(SymbolKind::Trait)),
409 Definition::TypeAlias(type_) => {
410 let mut h = Highlight::new(HlTag::Symbol(SymbolKind::TypeAlias));
412 if let Some(item) = type_.as_assoc_item(db) {
413 h |= HlMod::Associated;
414 match item.container(db) {
415 hir::AssocItemContainer::Impl(i) => {
416 if i.trait_(db).is_some() {
420 hir::AssocItemContainer::Trait(_t) => {
428 Definition::BuiltinType(_) => Highlight::new(HlTag::BuiltinType),
429 Definition::Static(s) => {
430 let mut h = Highlight::new(HlTag::Symbol(SymbolKind::Static));
439 Definition::SelfType(_) => Highlight::new(HlTag::Symbol(SymbolKind::Impl)),
440 Definition::GenericParam(it) => match it {
441 hir::GenericParam::TypeParam(_) => Highlight::new(HlTag::Symbol(SymbolKind::TypeParam)),
442 hir::GenericParam::ConstParam(_) => {
443 Highlight::new(HlTag::Symbol(SymbolKind::ConstParam))
445 hir::GenericParam::LifetimeParam(_) => {
446 Highlight::new(HlTag::Symbol(SymbolKind::LifetimeParam))
449 Definition::Local(local) => {
450 let tag = if local.is_self(db) {
451 HlTag::Symbol(SymbolKind::SelfParam)
452 } else if local.is_param(db) {
453 HlTag::Symbol(SymbolKind::ValueParam)
455 HlTag::Symbol(SymbolKind::Local)
457 let mut h = Highlight::new(tag);
458 let ty = local.ty(db);
459 if local.is_mut(db) || ty.is_mutable_reference() {
462 if local.is_ref(db) || ty.is_reference() {
463 h |= HlMod::Reference;
465 if ty.as_callable(db).is_some() || ty.impls_fnonce(db) {
466 h |= HlMod::Callable;
470 Definition::Label(_) => Highlight::new(HlTag::Symbol(SymbolKind::Label)),
471 Definition::BuiltinAttr(_) => Highlight::new(HlTag::Symbol(SymbolKind::BuiltinAttr)),
472 Definition::ToolModule(_) => Highlight::new(HlTag::Symbol(SymbolKind::ToolModule)),
475 let famous_defs = FamousDefs(sema, krate);
476 let def_crate = def.module(db).map(hir::Module::krate).or_else(|| match def {
477 Definition::Module(module) => Some(module.krate()),
480 let is_from_other_crate = def_crate != krate;
481 let is_from_builtin_crate =
482 def_crate.map_or(false, |def_crate| famous_defs.builtin_crates().any(|it| def_crate == it));
483 let is_builtin_type = matches!(def, Definition::BuiltinType(_));
484 let is_public = def.visibility(db) == Some(hir::Visibility::Public);
486 match (is_from_other_crate, is_builtin_type, is_public) {
487 (true, false, _) => h |= HlMod::Library,
488 (false, _, true) => h |= HlMod::Public,
492 if is_from_builtin_crate {
493 h |= HlMod::DefaultLibrary;
499 fn highlight_method_call_by_name_ref(
500 sema: &Semantics<RootDatabase>,
501 krate: Option<hir::Crate>,
502 name_ref: &ast::NameRef,
503 ) -> Option<Highlight> {
504 let mc = name_ref.syntax().parent().and_then(ast::MethodCallExpr::cast)?;
505 highlight_method_call(sema, krate, &mc)
508 fn highlight_method_call(
509 sema: &Semantics<RootDatabase>,
510 krate: Option<hir::Crate>,
511 method_call: &ast::MethodCallExpr,
512 ) -> Option<Highlight> {
513 let func = sema.resolve_method_call(method_call)?;
515 let mut h = SymbolKind::Function.into();
516 h |= HlMod::Associated;
518 if func.is_unsafe(sema.db) || sema.is_unsafe_method_call(method_call) {
521 if func.is_async(sema.db) {
524 if func.as_assoc_item(sema.db).and_then(|it| it.containing_trait(sema.db)).is_some() {
528 let famous_defs = FamousDefs(sema, krate);
529 let def_crate = func.module(sema.db).krate();
530 let is_from_other_crate = Some(def_crate) != krate;
531 let is_from_builtin_crate = famous_defs.builtin_crates().any(|it| def_crate == it);
532 let is_public = func.visibility(sema.db) == hir::Visibility::Public;
534 if is_from_other_crate {
536 } else if is_public {
540 if is_from_builtin_crate {
541 h |= HlMod::DefaultLibrary;
544 if let Some(self_param) = func.self_param(sema.db) {
545 match self_param.access(sema.db) {
546 hir::Access::Shared => h |= HlMod::Reference,
547 hir::Access::Exclusive => {
549 h |= HlMod::Reference;
551 hir::Access::Owned => {
552 if let Some(receiver_ty) =
553 method_call.receiver().and_then(|it| sema.type_of_expr(&it))
555 if !receiver_ty.adjusted().is_copy(sema.db) {
556 h |= HlMod::Consuming
565 fn highlight_name_by_syntax(name: ast::Name) -> Highlight {
566 let default = HlTag::UnresolvedReference;
568 let parent = match name.syntax().parent() {
570 _ => return default.into(),
573 let tag = match parent.kind() {
574 STRUCT => SymbolKind::Struct,
575 ENUM => SymbolKind::Enum,
576 VARIANT => SymbolKind::Variant,
577 UNION => SymbolKind::Union,
578 TRAIT => SymbolKind::Trait,
579 TYPE_ALIAS => SymbolKind::TypeAlias,
580 TYPE_PARAM => SymbolKind::TypeParam,
581 RECORD_FIELD => SymbolKind::Field,
582 MODULE => SymbolKind::Module,
583 FN => SymbolKind::Function,
584 CONST => SymbolKind::Const,
585 STATIC => SymbolKind::Static,
586 IDENT_PAT => SymbolKind::Local,
587 _ => return default.into(),
593 fn highlight_name_ref_by_syntax(
595 sema: &Semantics<RootDatabase>,
596 krate: Option<hir::Crate>,
598 let default = HlTag::UnresolvedReference;
600 let parent = match name.syntax().parent() {
602 _ => return default.into(),
605 match parent.kind() {
606 METHOD_CALL_EXPR => ast::MethodCallExpr::cast(parent)
607 .and_then(|it| highlight_method_call(sema, krate, &it))
608 .unwrap_or_else(|| SymbolKind::Function.into()),
610 let h = HlTag::Symbol(SymbolKind::Field);
611 let is_union = ast::FieldExpr::cast(parent)
612 .and_then(|field_expr| sema.resolve_field(&field_expr))
613 .map_or(false, |field| {
614 matches!(field.parent_def(sema.db), hir::VariantDef::Union(_))
623 let name_based_fallback = || {
624 if name.text().chars().next().unwrap_or_default().is_uppercase() {
625 SymbolKind::Struct.into()
627 SymbolKind::Module.into()
630 let path = match parent.parent().and_then(ast::Path::cast) {
632 _ => return name_based_fallback(),
634 let expr = match path.syntax().parent() {
635 Some(parent) => match_ast! {
637 ast::PathExpr(path) => path,
638 ast::MacroCall(_) => return SymbolKind::Macro.into(),
639 _ => return name_based_fallback(),
642 // within path, decide whether it is module or adt by checking for uppercase name
643 None => return name_based_fallback(),
645 let parent = match expr.syntax().parent() {
647 None => return default.into(),
650 match parent.kind() {
651 CALL_EXPR => SymbolKind::Function.into(),
652 _ => if name.text().chars().next().unwrap_or_default().is_uppercase() {
664 fn is_consumed_lvalue(node: &SyntaxNode, local: &hir::Local, db: &RootDatabase) -> bool {
665 // When lvalues are passed as arguments and they're not Copy, then mark them as Consuming.
666 parents_match(node.clone().into(), &[PATH_SEGMENT, PATH, PATH_EXPR, ARG_LIST])
667 && !local.ty(db).is_copy(db)
670 /// Returns true if the parent nodes of `node` all match the `SyntaxKind`s in `kinds` exactly.
671 fn parents_match(mut node: NodeOrToken<SyntaxNode, SyntaxToken>, mut kinds: &[SyntaxKind]) -> bool {
672 while let (Some(parent), [kind, rest @ ..]) = (&node.parent(), kinds) {
673 if parent.kind() != *kind {
677 // FIXME: Would be nice to get parent out of the match, but binding by-move and by-value
678 // in the same pattern is unstable: rust-lang/rust#68354.
679 node = node.parent().unwrap().into();
683 // Only true if we matched all expected kinds
687 fn parent_matches<N: AstNode>(token: &SyntaxToken) -> bool {
688 token.parent().map_or(false, |it| N::can_cast(it.kind()))