1mod render;
2
3#[cfg(test)]
4mod tests;
5
6use std::{iter, ops::Not};
7
8use either::Either;
9use hir::{
10 DisplayTarget, GenericDef, GenericSubstitution, HasCrate, HasSource, LangItem, Semantics,
11 db::DefDatabase,
12};
13use ide_db::{
14 FileRange, FxIndexSet, MiniCore, Ranker, RootDatabase,
15 defs::{Definition, IdentClass, NameRefClass, OperatorClass},
16 famous_defs::FamousDefs,
17 helpers::pick_best_token,
18 ra_fixture::UpmapFromRaFixture,
19};
20use itertools::{Itertools, multizip};
21use macros::UpmapFromRaFixture;
22use span::{Edition, TextRange};
23use syntax::{
24 AstNode, AstToken,
25 SyntaxKind::{self, *},
26 SyntaxNode, T, ast,
27};
28
29use crate::{
30 Analysis, FileId, FilePosition, NavigationTarget, RangeInfo, Runnable, TryToNav,
31 doc_links::token_as_doc_comment,
32 markdown_remove::remove_markdown,
33 markup::Markup,
34 navigation_target::UpmappingResult,
35 runnables::{runnable_fn, runnable_mod},
36};
37
38#[derive(Clone, Debug)]
39pub struct HoverConfig<'a> {
40 pub links_in_hover: bool,
41 pub memory_layout: Option<MemoryLayoutHoverConfig>,
42 pub documentation: bool,
43 pub keywords: bool,
44 pub format: HoverDocFormat,
45 pub max_trait_assoc_items_count: Option<usize>,
46 pub max_fields_count: Option<usize>,
47 pub max_enum_variants_count: Option<usize>,
48 pub max_subst_ty_len: SubstTyLen,
49 pub show_drop_glue: bool,
50 pub minicore: MiniCore<'a>,
51}
52
53#[derive(Clone, Debug, PartialEq, Eq)]
54pub enum SubstTyLen {
55 Unlimited,
56 LimitTo(usize),
57 Hide,
58}
59
60#[derive(Copy, Clone, Debug, PartialEq, Eq)]
61pub struct MemoryLayoutHoverConfig {
62 pub size: Option<MemoryLayoutHoverRenderKind>,
63 pub offset: Option<MemoryLayoutHoverRenderKind>,
64 pub alignment: Option<MemoryLayoutHoverRenderKind>,
65 pub padding: Option<MemoryLayoutHoverRenderKind>,
66 pub niches: bool,
67}
68
69#[derive(Copy, Clone, Debug, PartialEq, Eq)]
70pub enum MemoryLayoutHoverRenderKind {
71 Decimal,
72 Hexadecimal,
73 Both,
74}
75
76#[derive(Clone, Debug, PartialEq, Eq)]
77pub enum HoverDocFormat {
78 Markdown,
79 PlainText,
80}
81
82#[derive(Debug, Clone, Hash, PartialEq, Eq, UpmapFromRaFixture)]
83pub enum HoverAction {
84 Runnable(Runnable),
85 Implementation(FilePosition),
86 Reference(FilePosition),
87 GoToType(Vec<HoverGotoTypeData>),
88}
89
90impl HoverAction {
91 fn goto_type_from_targets(
92 sema: &Semantics<'_, RootDatabase>,
93 targets: Vec<hir::ModuleDef>,
94 edition: Edition,
95 ) -> Option<Self> {
96 let db = sema.db;
97 let targets = targets
98 .into_iter()
99 .filter_map(|it| {
100 Some(HoverGotoTypeData {
101 mod_path: render::path(
102 db,
103 it.module(db)?,
104 it.name(db).map(|name| name.display(db, edition).to_string()),
105 edition,
106 ),
107 nav: it.try_to_nav(sema)?.call_site(),
108 })
109 })
110 .collect::<Vec<_>>();
111 targets.is_empty().not().then_some(HoverAction::GoToType(targets))
112 }
113}
114
115#[derive(Debug, Clone, Eq, PartialEq, Hash, UpmapFromRaFixture)]
116pub struct HoverGotoTypeData {
117 pub mod_path: String,
118 pub nav: NavigationTarget,
119}
120
121#[derive(Clone, Debug, Default, Hash, PartialEq, Eq, UpmapFromRaFixture)]
123pub struct HoverResult {
124 pub markup: Markup,
125 pub actions: Vec<HoverAction>,
126}
127
128pub(crate) fn hover(
135 db: &RootDatabase,
136 frange @ FileRange { file_id, range }: FileRange,
137 config: &HoverConfig<'_>,
138) -> Option<RangeInfo<HoverResult>> {
139 let sema = &hir::Semantics::new(db);
140 let file = sema.parse_guess_edition(file_id).syntax().clone();
141 let edition =
142 sema.attach_first_edition(file_id).map(|it| it.edition(db)).unwrap_or(Edition::CURRENT);
143 let display_target = sema.first_crate(file_id)?.to_display_target(db);
144 let mut res = if range.is_empty() {
145 hover_offset(
146 sema,
147 FilePosition { file_id, offset: range.start() },
148 file,
149 config,
150 edition,
151 display_target,
152 )
153 } else {
154 hover_ranged(sema, frange, file, config, edition, display_target)
155 }?;
156
157 if let HoverDocFormat::PlainText = config.format {
158 res.info.markup = remove_markdown(res.info.markup.as_str()).into();
159 }
160 Some(res)
161}
162
163#[allow(clippy::field_reassign_with_default)]
164fn hover_offset(
165 sema: &Semantics<'_, RootDatabase>,
166 FilePosition { file_id, offset }: FilePosition,
167 file: SyntaxNode,
168 config: &HoverConfig<'_>,
169 edition: Edition,
170 display_target: DisplayTarget,
171) -> Option<RangeInfo<HoverResult>> {
172 let original_token = pick_best_token(file.token_at_offset(offset), |kind| match kind {
173 IDENT
174 | INT_NUMBER
175 | LIFETIME_IDENT
176 | T![self]
177 | T![super]
178 | T![crate]
179 | T![Self]
180 | T![_] => 4,
181 T!['['] | T![']'] | T![?] | T![*] | T![-] | T![!] | T![|] => 3,
183 kind if kind.is_keyword(edition) => 2,
184 T!['('] | T![')'] => 2,
185 kind if kind.is_trivia() => 0,
186 _ => 1,
187 })?;
188
189 if let Some(doc_comment) = token_as_doc_comment(&original_token) {
190 cov_mark::hit!(no_highlight_on_comment_hover);
191 return doc_comment.get_definition_with_descend_at(sema, offset, |def, node, range| {
192 let res = hover_for_definition(
193 sema,
194 file_id,
195 def,
196 None,
197 &node,
198 None,
199 false,
200 config,
201 edition,
202 display_target,
203 );
204 Some(RangeInfo::new(range, res))
205 });
206 }
207
208 if let Some((range, _, _, resolution)) =
209 sema.check_for_format_args_template(original_token.clone(), offset)
210 {
211 let res = hover_for_definition(
212 sema,
213 file_id,
214 Definition::from(resolution?),
215 None,
216 &original_token.parent()?,
217 None,
218 false,
219 config,
220 edition,
221 display_target,
222 );
223 return Some(RangeInfo::new(range, res));
224 }
225
226 if let Some(literal) = ast::String::cast(original_token.clone())
227 && let Some((analysis, fixture_analysis)) =
228 Analysis::from_ra_fixture(sema, literal.clone(), &literal, config.minicore)
229 {
230 let (virtual_file_id, virtual_offset) = fixture_analysis.map_offset_down(offset)?;
231 return analysis
232 .hover(
233 config,
234 FileRange { file_id: virtual_file_id, range: TextRange::empty(virtual_offset) },
235 )
236 .ok()??
237 .upmap_from_ra_fixture(&fixture_analysis, virtual_file_id, file_id)
238 .ok();
239 }
240
241 let mut descended = sema.descend_into_macros(original_token.clone());
244
245 let ranker = Ranker::from_token(&original_token);
246
247 descended.sort_by_cached_key(|tok| !ranker.rank_token(tok));
248
249 let mut res = vec![];
250 for token in descended {
251 let is_same_kind = token.kind() == ranker.kind;
252 let lint_hover = (|| {
253 let attr = token.parent_ancestors().find_map(ast::Attr::cast)?;
255 render::try_for_lint(&attr, &token)
256 })();
257 if let Some(lint_hover) = lint_hover {
258 res.push(lint_hover);
259 continue;
260 }
261 let definitions = (|| {
262 Some(
263 'a: {
264 let node = token.parent()?;
265
266 if let Some(name) = ast::NameRef::cast(node.clone())
268 && let Some(path_seg) =
269 name.syntax().parent().and_then(ast::PathSegment::cast)
270 && let Some(macro_call) = path_seg
271 .parent_path()
272 .syntax()
273 .parent()
274 .and_then(ast::MacroCall::cast)
275 && let Some(macro_) = sema.resolve_macro_call(¯o_call) {
276 break 'a vec![(
277 (Definition::Macro(macro_), None),
278 sema.resolve_macro_call_arm(¯o_call),
279 false,
280 node,
281 )];
282 }
283
284 match IdentClass::classify_node(sema, &node)? {
285 IdentClass::Operator(OperatorClass::Await(_)) => return None,
288
289 IdentClass::NameRefClass(NameRefClass::ExternCrateShorthand {
290 decl,
291 ..
292 }) => {
293 vec![((Definition::ExternCrateDecl(decl), None), None, false, node)]
294 }
295
296 class => {
297 let render_extras = matches!(class, IdentClass::NameClass(_))
298 || ast::NameRef::cast(node.clone()).is_some_and(|name_ref| name_ref.token_kind() == SyntaxKind::SELF_TYPE_KW);
300 multizip((
301 class.definitions(),
302 iter::repeat(None),
303 iter::repeat(render_extras),
304 iter::repeat(node),
305 ))
306 .collect::<Vec<_>>()
307 }
308 }
309 }
310 .into_iter()
311 .unique_by(|&((def, _), _, _, _)| def)
312 .map(|((def, subst), macro_arm, hovered_definition, node)| {
313 hover_for_definition(
314 sema,
315 file_id,
316 def,
317 subst,
318 &node,
319 macro_arm,
320 hovered_definition,
321 config,
322 edition,
323 display_target,
324 )
325 })
326 .collect::<Vec<_>>(),
327 )
328 })();
329 if let Some(definitions) = definitions {
330 res.extend(definitions);
331 continue;
332 }
333 let keywords = || render::keyword(sema, config, &token, edition, display_target);
334 let underscore = || {
335 if !is_same_kind {
336 return None;
337 }
338 render::underscore(sema, config, &token, edition, display_target)
339 };
340 let rest_pat = || {
341 if !is_same_kind || token.kind() != DOT2 {
342 return None;
343 }
344
345 let rest_pat = token.parent().and_then(ast::RestPat::cast)?;
346 let record_pat_field_list =
347 rest_pat.syntax().parent().and_then(ast::RecordPatFieldList::cast)?;
348
349 let record_pat =
350 record_pat_field_list.syntax().parent().and_then(ast::RecordPat::cast)?;
351
352 Some(render::struct_rest_pat(sema, config, &record_pat, edition, display_target))
353 };
354 let call = || {
355 if !is_same_kind || token.kind() != T!['('] && token.kind() != T![')'] {
356 return None;
357 }
358 let arg_list = token.parent().and_then(ast::ArgList::cast)?.syntax().parent()?;
359 let call_expr = syntax::match_ast! {
360 match arg_list {
361 ast::CallExpr(expr) => expr.into(),
362 ast::MethodCallExpr(expr) => expr.into(),
363 _ => return None,
364 }
365 };
366 render::type_info_of(sema, config, &Either::Left(call_expr), edition, display_target)
367 };
368 let closure = || {
369 if !is_same_kind || token.kind() != T![|] {
370 return None;
371 }
372 let c = token.parent().and_then(|x| x.parent()).and_then(ast::ClosureExpr::cast)?;
373 render::closure_expr(sema, config, c, edition, display_target)
374 };
375 let literal = || {
376 render::literal(sema, original_token.clone(), display_target)
377 .map(|markup| HoverResult { markup, actions: vec![] })
378 };
379 if let Some(result) = keywords()
380 .or_else(underscore)
381 .or_else(rest_pat)
382 .or_else(call)
383 .or_else(closure)
384 .or_else(literal)
385 {
386 res.push(result)
387 }
388 }
389
390 res.into_iter()
391 .unique()
392 .reduce(|mut acc: HoverResult, HoverResult { markup, actions }| {
393 acc.actions.extend(actions);
394 acc.markup = Markup::from(format!("{}\n\n---\n{markup}", acc.markup));
395 acc
396 })
397 .map(|mut res: HoverResult| {
398 res.actions = dedupe_or_merge_hover_actions(res.actions);
399 RangeInfo::new(original_token.text_range(), res)
400 })
401}
402
403fn hover_ranged(
404 sema: &Semantics<'_, RootDatabase>,
405 FileRange { file_id, range }: FileRange,
406 file: SyntaxNode,
407 config: &HoverConfig<'_>,
408 edition: Edition,
409 display_target: DisplayTarget,
410) -> Option<RangeInfo<HoverResult>> {
411 let expr_or_pat = file
413 .covering_element(range)
414 .ancestors()
415 .take_while(|it| ast::MacroCall::can_cast(it.kind()) || !ast::Item::can_cast(it.kind()))
416 .find_map(Either::<ast::Expr, ast::Pat>::cast)?;
417 let res = match &expr_or_pat {
418 Either::Left(ast::Expr::TryExpr(try_expr)) => {
419 render::try_expr(sema, config, try_expr, edition, display_target)
420 }
421 Either::Left(ast::Expr::PrefixExpr(prefix_expr))
422 if prefix_expr.op_kind() == Some(ast::UnaryOp::Deref) =>
423 {
424 render::deref_expr(sema, config, prefix_expr, edition, display_target)
425 }
426 Either::Left(ast::Expr::Literal(literal)) => {
427 if let Some(literal) = ast::String::cast(literal.token())
428 && let Some((analysis, fixture_analysis)) =
429 Analysis::from_ra_fixture(sema, literal.clone(), &literal, config.minicore)
430 {
431 let (virtual_file_id, virtual_range) = fixture_analysis.map_range_down(range)?;
432 return analysis
433 .hover(config, FileRange { file_id: virtual_file_id, range: virtual_range })
434 .ok()??
435 .upmap_from_ra_fixture(&fixture_analysis, virtual_file_id, file_id)
436 .ok();
437 }
438 None
439 }
440 _ => None,
441 };
442 let res =
443 res.or_else(|| render::type_info_of(sema, config, &expr_or_pat, edition, display_target));
444 res.map(|it| {
445 let range = match expr_or_pat {
446 Either::Left(it) => it.syntax().text_range(),
447 Either::Right(it) => it.syntax().text_range(),
448 };
449 RangeInfo::new(range, it)
450 })
451}
452
453pub(crate) fn hover_for_definition(
455 sema: &Semantics<'_, RootDatabase>,
456 file_id: FileId,
457 def: Definition,
458 subst: Option<GenericSubstitution<'_>>,
459 scope_node: &SyntaxNode,
460 macro_arm: Option<u32>,
461 render_extras: bool,
462 config: &HoverConfig<'_>,
463 edition: Edition,
464 display_target: DisplayTarget,
465) -> HoverResult {
466 let famous_defs = match &def {
467 Definition::BuiltinType(_) => sema.scope(scope_node).map(|it| FamousDefs(sema, it.krate())),
468 _ => None,
469 };
470
471 let db = sema.db;
472 let def_ty = match def {
473 Definition::Local(it) => Some(it.ty(db)),
474 Definition::GenericParam(hir::GenericParam::ConstParam(it)) => Some(it.ty(db)),
475 Definition::GenericParam(hir::GenericParam::TypeParam(it)) => Some(it.ty(db)),
476 Definition::Field(field) => Some(field.ty(db).to_type(db)),
477 Definition::TupleField(it) => Some(it.ty(db)),
478 Definition::Function(it) => Some(it.ty(db)),
479 Definition::Adt(it) => Some(it.ty(db)),
480 Definition::Const(it) => Some(it.ty(db)),
481 Definition::Static(it) => Some(it.ty(db)),
482 Definition::TypeAlias(it) => Some(it.ty(db)),
483 Definition::BuiltinType(it) => Some(it.ty(db)),
484 _ => None,
485 };
486 let notable_traits = def_ty.map(|ty| notable_traits(db, &ty)).unwrap_or_default();
487 let subst_types = subst.map(|subst| subst.types(db));
488
489 let (markup, range_map) = render::definition(
490 sema.db,
491 def,
492 famous_defs.as_ref(),
493 ¬able_traits,
494 macro_arm,
495 render_extras,
496 subst_types.as_ref(),
497 config,
498 edition,
499 display_target,
500 );
501 HoverResult {
502 markup: render::process_markup(sema.db, def, &markup, range_map, config),
503 actions: [
504 show_fn_references_action(sema, def),
505 show_implementations_action(sema, def),
506 runnable_action(sema, def, file_id),
507 goto_type_action_for_def(sema, def, ¬able_traits, subst_types, edition),
508 ]
509 .into_iter()
510 .flatten()
511 .collect(),
512 }
513}
514
515fn notable_traits<'db>(
516 db: &'db RootDatabase,
517 ty: &hir::Type<'db>,
518) -> Vec<(hir::Trait, Vec<(Option<hir::Type<'db>>, hir::Name)>)> {
519 if ty.is_unknown() {
520 return Vec::new();
523 }
524
525 db.notable_traits_in_deps(ty.krate(db).into())
526 .iter()
527 .flat_map(|it| &**it)
528 .filter_map(move |&trait_| {
529 let trait_ = trait_.into();
530 ty.impls_trait(db, trait_, &[]).then(|| {
531 (
532 trait_,
533 trait_
534 .items(db)
535 .into_iter()
536 .filter_map(hir::AssocItem::as_type_alias)
537 .map(|alias| {
538 (ty.normalize_trait_assoc_type(db, &[], alias), alias.name(db))
539 })
540 .collect::<Vec<_>>(),
541 )
542 })
543 })
544 .sorted_by_cached_key(|(trait_, _)| trait_.name(db))
545 .collect::<Vec<_>>()
546}
547
548fn show_implementations_action(
549 sema: &Semantics<'_, RootDatabase>,
550 def: Definition,
551) -> Option<HoverAction> {
552 fn to_action(nav_target: NavigationTarget) -> HoverAction {
553 HoverAction::Implementation(FilePosition {
554 file_id: nav_target.file_id,
555 offset: nav_target.focus_or_full_range().start(),
556 })
557 }
558
559 let adt = match def {
560 Definition::Trait(it) => {
561 return it.try_to_nav(sema).map(UpmappingResult::call_site).map(to_action);
562 }
563 Definition::Adt(it) => Some(it),
564 Definition::SelfType(it) => it.self_ty(sema.db).as_adt(),
565 _ => None,
566 }?;
567 adt.try_to_nav(sema).map(UpmappingResult::call_site).map(to_action)
568}
569
570fn show_fn_references_action(
571 sema: &Semantics<'_, RootDatabase>,
572 def: Definition,
573) -> Option<HoverAction> {
574 match def {
575 Definition::Function(it) => {
576 it.try_to_nav(sema).map(UpmappingResult::call_site).map(|nav_target| {
577 HoverAction::Reference(FilePosition {
578 file_id: nav_target.file_id,
579 offset: nav_target.focus_or_full_range().start(),
580 })
581 })
582 }
583 _ => None,
584 }
585}
586
587fn runnable_action(
588 sema: &hir::Semantics<'_, RootDatabase>,
589 def: Definition,
590 file_id: FileId,
591) -> Option<HoverAction> {
592 match def {
593 Definition::Module(it) => runnable_mod(sema, it).map(HoverAction::Runnable),
594 Definition::Function(func) => {
595 let src = func.source(sema.db)?;
596 if src.file_id.file_id().is_none_or(|f| f.file_id(sema.db) != file_id) {
597 cov_mark::hit!(hover_macro_generated_struct_fn_doc_comment);
598 cov_mark::hit!(hover_macro_generated_struct_fn_doc_attr);
599 return None;
600 }
601
602 runnable_fn(sema, func).map(HoverAction::Runnable)
603 }
604 _ => None,
605 }
606}
607
608fn goto_type_action_for_def(
609 sema: &Semantics<'_, RootDatabase>,
610 def: Definition,
611 notable_traits: &[(hir::Trait, Vec<(Option<hir::Type<'_>>, hir::Name)>)],
612 subst_types: Option<Vec<(hir::Symbol, hir::Type<'_>)>>,
613 edition: Edition,
614) -> Option<HoverAction> {
615 let db = sema.db;
616 let mut targets: Vec<hir::ModuleDef> = Vec::new();
617 let mut push_new_def = |item: hir::ModuleDef| {
618 if !targets.contains(&item) {
619 targets.push(item);
620 }
621 };
622
623 for &(trait_, ref assocs) in notable_traits {
624 push_new_def(trait_.into());
625 assocs.iter().filter_map(|(ty, _)| ty.as_ref()).for_each(|ty| {
626 walk_and_push_ty(db, ty, &mut push_new_def);
627 });
628 }
629
630 if let Ok(generic_def) = GenericDef::try_from(def) {
631 generic_def.type_or_const_params(db).into_iter().for_each(|it| {
632 walk_and_push_ty(db, &it.ty(db), &mut push_new_def);
633 });
634 }
635
636 let ty = match def {
637 Definition::Local(it) => Some(it.ty(db)),
638 Definition::Field(field) => Some(field.ty(db).to_type(db)),
639 Definition::TupleField(field) => Some(field.ty(db)),
640 Definition::Const(it) => Some(it.ty(db)),
641 Definition::Static(it) => Some(it.ty(db)),
642 Definition::Function(func) => {
643 for param in func.assoc_fn_params(db) {
644 walk_and_push_ty(db, param.ty(), &mut push_new_def);
645 }
646 Some(func.ret_type(db))
647 }
648 Definition::GenericParam(hir::GenericParam::ConstParam(it)) => Some(it.ty(db)),
649 Definition::GenericParam(hir::GenericParam::TypeParam(it)) => Some(it.ty(db)),
650 _ => None,
651 };
652 if let Some(ty) = ty {
653 walk_and_push_ty(db, &ty, &mut push_new_def);
654 }
655
656 if let Some(subst_types) = subst_types {
657 for (_, ty) in subst_types {
658 walk_and_push_ty(db, &ty, &mut push_new_def);
659 }
660 }
661
662 HoverAction::goto_type_from_targets(sema, targets, edition)
663}
664
665fn walk_and_push_ty(
666 db: &RootDatabase,
667 ty: &hir::Type<'_>,
668 push_new_def: &mut dyn FnMut(hir::ModuleDef),
669) {
670 ty.walk(db, |t| {
671 if let Some(adt) = t.as_adt() {
672 push_new_def(adt.into());
673 } else if let Some(trait_) = t.as_dyn_trait() {
674 push_new_def(trait_.into());
675 } else if let Some(traits) = t.as_impl_traits(db) {
676 traits.for_each(|it| push_new_def(it.into()));
677 } else if let Some(trait_) = t.as_associated_type_parent_trait(db) {
678 push_new_def(trait_.into());
679 } else if let Some(tp) = t.as_type_param(db) {
680 let sized_trait = LangItem::Sized.resolve_trait(db, t.krate(db).into());
681 tp.trait_bounds(db)
682 .into_iter()
683 .filter(|&it| Some(it.into()) != sized_trait)
684 .for_each(|it| push_new_def(it.into()));
685 }
686 });
687}
688
689fn dedupe_or_merge_hover_actions(actions: Vec<HoverAction>) -> Vec<HoverAction> {
690 let mut deduped_actions = Vec::with_capacity(actions.len());
691 let mut go_to_type_targets = FxIndexSet::default();
692
693 let mut seen_implementation = false;
694 let mut seen_reference = false;
695 let mut seen_runnable = false;
696 for action in actions {
697 match action {
698 HoverAction::GoToType(targets) => {
699 go_to_type_targets.extend(targets);
700 }
701 HoverAction::Implementation(..) => {
702 if !seen_implementation {
703 seen_implementation = true;
704 deduped_actions.push(action);
705 }
706 }
707 HoverAction::Reference(..) => {
708 if !seen_reference {
709 seen_reference = true;
710 deduped_actions.push(action);
711 }
712 }
713 HoverAction::Runnable(..) => {
714 if !seen_runnable {
715 seen_runnable = true;
716 deduped_actions.push(action);
717 }
718 }
719 };
720 }
721
722 if !go_to_type_targets.is_empty() {
723 deduped_actions.push(HoverAction::GoToType(
724 go_to_type_targets.into_iter().sorted_by(|a, b| a.mod_path.cmp(&b.mod_path)).collect(),
725 ));
726 }
727
728 deduped_actions
729}