crates/hir/src/source_analyzer.rs

   1 //! Lookup hir elements using positions in the source code. This is a lossy
   2 //! transformation: in general, a single source might correspond to several
   3 //! modules, functions, etc, due to macros, cfgs and `#[path=]` attributes on
   4 //! modules.
   5 //!
   6 //! So, this modules should not be used during hir construction, it exists
   7 //! purely for "IDE needs".
   8 use std::{iter::once, sync::Arc};
   9
  10 use hir_def::{
  11     body::{
  12         self,
  13         scope::{ExprScopes, ScopeId},
  14         Body, BodySourceMap,
  15     },
  16     expr::{ExprId, Pat, PatId},
  17     path::{ModPath, Path, PathKind},
  18     resolver::{resolver_for_scope, Resolver, TypeNs, ValueNs},
  19     AsMacroCall, DefWithBodyId, FieldId, FunctionId, LocalFieldId, VariantId,
  20 };
  21 use hir_expand::{hygiene::Hygiene, name::AsName, HirFileId, InFile};
  22 use hir_ty::{
  23     diagnostics::{record_literal_missing_fields, record_pattern_missing_fields},
  24     InferenceResult, Interner, Substitution, TyExt, TyLoweringContext,
  25 };
  26 use syntax::{
  27     ast::{self, AstNode},
  28     SyntaxNode, TextRange, TextSize,
  29 };
  30
  31 use crate::{
  32     db::HirDatabase, semantics::PathResolution, Adt, BuiltinType, Const, Field, Function, Local,
  33     MacroDef, ModuleDef, Static, Struct, Trait, Type, TypeAlias, TypeParam, Variant,
  34 };
  35 use base_db::CrateId;
  36
  37 /// `SourceAnalyzer` is a convenience wrapper which exposes HIR API in terms of
  38 /// original source files. It should not be used inside the HIR itself.
  39 #[derive(Debug)]
  40 pub(crate) struct SourceAnalyzer {
  41     pub(crate) file_id: HirFileId,
  42     pub(crate) resolver: Resolver,
  43     body: Option<Arc<Body>>,
  44     body_source_map: Option<Arc<BodySourceMap>>,
  45     infer: Option<Arc<InferenceResult>>,
  46     scopes: Option<Arc<ExprScopes>>,
  47 }
  48
  49 impl SourceAnalyzer {
  50     pub(crate) fn new_for_body(
  51         db: &dyn HirDatabase,
  52         def: DefWithBodyId,
  53         node: InFile<&SyntaxNode>,
  54         offset: Option<TextSize>,
  55     ) -> SourceAnalyzer {
  56         let (body, source_map) = db.body_with_source_map(def);
  57         let scopes = db.expr_scopes(def);
  58         let scope = match offset {
  59             None => scope_for(&scopes, &source_map, node),
  60             Some(offset) => scope_for_offset(db, &scopes, &source_map, node.with_value(offset)),
  61         };
  62         let resolver = resolver_for_scope(db.upcast(), def, scope);
  63         SourceAnalyzer {
  64             resolver,
  65             body: Some(body),
  66             body_source_map: Some(source_map),
  67             infer: Some(db.infer(def)),
  68             scopes: Some(scopes),
  69             file_id: node.file_id,
  70         }
  71     }
  72
  73     pub(crate) fn new_for_resolver(
  74         resolver: Resolver,
  75         node: InFile<&SyntaxNode>,
  76     ) -> SourceAnalyzer {
  77         SourceAnalyzer {
  78             resolver,
  79             body: None,
  80             body_source_map: None,
  81             infer: None,
  82             scopes: None,
  83             file_id: node.file_id,
  84         }
  85     }
  86
  87     fn expr_id(&self, db: &dyn HirDatabase, expr: &ast::Expr) -> Option<ExprId> {
  88         let src = match expr {
  89             ast::Expr::MacroCall(call) => {
  90                 self.expand_expr(db, InFile::new(self.file_id, call.clone()))?
  91             }
  92             _ => InFile::new(self.file_id, expr.clone()),
  93         };
  94         let sm = self.body_source_map.as_ref()?;
  95         sm.node_expr(src.as_ref())
  96     }
  97
  98     fn pat_id(&self, pat: &ast::Pat) -> Option<PatId> {
  99         // FIXME: macros, see `expr_id`
 100         let src = InFile { file_id: self.file_id, value: pat };
 101         self.body_source_map.as_ref()?.node_pat(src)
 102     }
 103
 104     fn expand_expr(
 105         &self,
 106         db: &dyn HirDatabase,
 107         expr: InFile<ast::MacroCall>,
 108     ) -> Option<InFile<ast::Expr>> {
 109         let macro_file = self.body_source_map.as_ref()?.node_macro_file(expr.as_ref())?;
 110         let expanded = db.parse_or_expand(macro_file)?;
 111
 112         let res = match ast::MacroCall::cast(expanded.clone()) {
 113             Some(call) => self.expand_expr(db, InFile::new(macro_file, call))?,
 114             _ => InFile::new(macro_file, ast::Expr::cast(expanded)?),
 115         };
 116         Some(res)
 117     }
 118
 119     pub(crate) fn type_of_expr(&self, db: &dyn HirDatabase, expr: &ast::Expr) -> Option<Type> {
 120         let expr_id = self.expr_id(db, expr)?;
 121         let ty = self.infer.as_ref()?[expr_id].clone();
 122         Type::new_with_resolver(db, &self.resolver, ty)
 123     }
 124
 125     pub(crate) fn type_of_pat(&self, db: &dyn HirDatabase, pat: &ast::Pat) -> Option<Type> {
 126         let pat_id = self.pat_id(pat)?;
 127         let ty = self.infer.as_ref()?[pat_id].clone();
 128         Type::new_with_resolver(db, &self.resolver, ty)
 129     }
 130
 131     pub(crate) fn type_of_self(
 132         &self,
 133         db: &dyn HirDatabase,
 134         param: &ast::SelfParam,
 135     ) -> Option<Type> {
 136         let src = InFile { file_id: self.file_id, value: param };
 137         let pat_id = self.body_source_map.as_ref()?.node_self_param(src)?;
 138         let ty = self.infer.as_ref()?[pat_id].clone();
 139         Type::new_with_resolver(db, &self.resolver, ty)
 140     }
 141
 142     pub(crate) fn resolve_method_call(
 143         &self,
 144         db: &dyn HirDatabase,
 145         call: &ast::MethodCallExpr,
 146     ) -> Option<(FunctionId, Substitution)> {
 147         let expr_id = self.expr_id(db, &call.clone().into())?;
 148         self.infer.as_ref()?.method_resolution(expr_id)
 149     }
 150
 151     pub(crate) fn resolve_field(
 152         &self,
 153         db: &dyn HirDatabase,
 154         field: &ast::FieldExpr,
 155     ) -> Option<Field> {
 156         let expr_id = self.expr_id(db, &field.clone().into())?;
 157         self.infer.as_ref()?.field_resolution(expr_id).map(|it| it.into())
 158     }
 159
 160     pub(crate) fn resolve_record_field(
 161         &self,
 162         db: &dyn HirDatabase,
 163         field: &ast::RecordExprField,
 164     ) -> Option<(Field, Option<Local>, Type)> {
 165         let record_expr = ast::RecordExpr::cast(field.syntax().parent().and_then(|p| p.parent())?)?;
 166         let expr = ast::Expr::from(record_expr);
 167         let expr_id = self.body_source_map.as_ref()?.node_expr(InFile::new(self.file_id, &expr))?;
 168
 169         let local_name = field.field_name()?.as_name();
 170         let local = if field.name_ref().is_some() {
 171             None
 172         } else {
 173             let path = ModPath::from_segments(PathKind::Plain, once(local_name.clone()));
 174             match self.resolver.resolve_path_in_value_ns_fully(db.upcast(), &path) {
 175                 Some(ValueNs::LocalBinding(pat_id)) => {
 176                     Some(Local { pat_id, parent: self.resolver.body_owner()? })
 177                 }
 178                 _ => None,
 179             }
 180         };
 181         let (_, subst) = self.infer.as_ref()?.type_of_expr.get(expr_id)?.as_adt()?;
 182         let variant = self.infer.as_ref()?.variant_resolution_for_expr(expr_id)?;
 183         let variant_data = variant.variant_data(db.upcast());
 184         let field = FieldId { parent: variant, local_id: variant_data.field(&local_name)? };
 185         let field_ty =
 186             db.field_types(variant).get(field.local_id)?.clone().substitute(&Interner, subst);
 187         Some((field.into(), local, Type::new_with_resolver(db, &self.resolver, field_ty)?))
 188     }
 189
 190     pub(crate) fn resolve_record_pat_field(
 191         &self,
 192         db: &dyn HirDatabase,
 193         field: &ast::RecordPatField,
 194     ) -> Option<Field> {
 195         let field_name = field.field_name()?.as_name();
 196         let record_pat = ast::RecordPat::cast(field.syntax().parent().and_then(|p| p.parent())?)?;
 197         let pat_id = self.pat_id(&record_pat.into())?;
 198         let variant = self.infer.as_ref()?.variant_resolution_for_pat(pat_id)?;
 199         let variant_data = variant.variant_data(db.upcast());
 200         let field = FieldId { parent: variant, local_id: variant_data.field(&field_name)? };
 201         Some(field.into())
 202     }
 203
 204     pub(crate) fn resolve_macro_call(
 205         &self,
 206         db: &dyn HirDatabase,
 207         macro_call: InFile<&ast::MacroCall>,
 208     ) -> Option<MacroDef> {
 209         let ctx = body::LowerCtx::new(db.upcast(), macro_call.file_id);
 210         let path = macro_call.value.path().and_then(|ast| Path::from_src(ast, &ctx))?;
 211         self.resolver.resolve_path_as_macro(db.upcast(), path.mod_path()).map(|it| it.into())
 212     }
 213
 214     pub(crate) fn resolve_bind_pat_to_const(
 215         &self,
 216         db: &dyn HirDatabase,
 217         pat: &ast::IdentPat,
 218     ) -> Option<ModuleDef> {
 219         let pat_id = self.pat_id(&pat.clone().into())?;
 220         let body = self.body.as_ref()?;
 221         let path = match &body[pat_id] {
 222             Pat::Path(path) => path,
 223             _ => return None,
 224         };
 225         let res = resolve_hir_path(db, &self.resolver, path)?;
 226         match res {
 227             PathResolution::Def(def) => Some(def),
 228             _ => None,
 229         }
 230     }
 231
 232     pub(crate) fn resolve_path(
 233         &self,
 234         db: &dyn HirDatabase,
 235         path: &ast::Path,
 236     ) -> Option<PathResolution> {
 237         let parent = || path.syntax().parent();
 238         let mut prefer_value_ns = false;
 239         if let Some(path_expr) = parent().and_then(ast::PathExpr::cast) {
 240             let expr_id = self.expr_id(db, &path_expr.into())?;
 241             let infer = self.infer.as_ref()?;
 242             if let Some(assoc) = infer.assoc_resolutions_for_expr(expr_id) {
 243                 return Some(PathResolution::AssocItem(assoc.into()));
 244             }
 245             if let Some(VariantId::EnumVariantId(variant)) =
 246                 infer.variant_resolution_for_expr(expr_id)
 247             {
 248                 return Some(PathResolution::Def(ModuleDef::Variant(variant.into())));
 249             }
 250             prefer_value_ns = true;
 251         }
 252
 253         if let Some(path_pat) = parent().and_then(ast::PathPat::cast) {
 254             let pat_id = self.pat_id(&path_pat.into())?;
 255             if let Some(assoc) = self.infer.as_ref()?.assoc_resolutions_for_pat(pat_id) {
 256                 return Some(PathResolution::AssocItem(assoc.into()));
 257             }
 258             if let Some(VariantId::EnumVariantId(variant)) =
 259                 self.infer.as_ref()?.variant_resolution_for_pat(pat_id)
 260             {
 261                 return Some(PathResolution::Def(ModuleDef::Variant(variant.into())));
 262             }
 263         }
 264
 265         if let Some(rec_lit) = parent().and_then(ast::RecordExpr::cast) {
 266             let expr_id = self.expr_id(db, &rec_lit.into())?;
 267             if let Some(VariantId::EnumVariantId(variant)) =
 268                 self.infer.as_ref()?.variant_resolution_for_expr(expr_id)
 269             {
 270                 return Some(PathResolution::Def(ModuleDef::Variant(variant.into())));
 271             }
 272         }
 273
 274         if let Some(pat) = parent()
 275             .and_then(ast::RecordPat::cast)
 276             .map(ast::Pat::from)
 277             .or_else(|| parent().and_then(ast::TupleStructPat::cast).map(ast::Pat::from))
 278         {
 279             let pat_id = self.pat_id(&pat)?;
 280             if let Some(VariantId::EnumVariantId(variant)) =
 281                 self.infer.as_ref()?.variant_resolution_for_pat(pat_id)
 282             {
 283                 return Some(PathResolution::Def(ModuleDef::Variant(variant.into())));
 284             }
 285         }
 286
 287         // This must be a normal source file rather than macro file.
 288         let hygiene = Hygiene::new(db.upcast(), self.file_id);
 289         let ctx = body::LowerCtx::with_hygiene(db.upcast(), &hygiene);
 290         let hir_path = Path::from_src(path.clone(), &ctx)?;
 291
 292         // Case where path is a qualifier of another path, e.g. foo::bar::Baz where we are
 293         // trying to resolve foo::bar.
 294         if let Some(outer_path) = parent().and_then(ast::Path::cast) {
 295             if let Some(qualifier) = outer_path.qualifier() {
 296                 if path == &qualifier {
 297                     return resolve_hir_path_qualifier(db, &self.resolver, &hir_path);
 298                 }
 299             }
 300         }
 301         // Case where path is a qualifier of a use tree, e.g. foo::bar::{Baz, Qux} where we are
 302         // trying to resolve foo::bar.
 303         if let Some(use_tree) = parent().and_then(ast::UseTree::cast) {
 304             if let Some(qualifier) = use_tree.path() {
 305                 if path == &qualifier && use_tree.coloncolon_token().is_some() {
 306                     return resolve_hir_path_qualifier(db, &self.resolver, &hir_path);
 307                 }
 308             }
 309         }
 310
 311         if parent().map_or(false, |it| ast::Visibility::can_cast(it.kind())) {
 312             resolve_hir_path_qualifier(db, &self.resolver, &hir_path)
 313         } else {
 314             resolve_hir_path_(db, &self.resolver, &hir_path, prefer_value_ns)
 315         }
 316     }
 317
 318     pub(crate) fn record_literal_missing_fields(
 319         &self,
 320         db: &dyn HirDatabase,
 321         literal: &ast::RecordExpr,
 322     ) -> Option<Vec<(Field, Type)>> {
 323         let krate = self.resolver.krate()?;
 324         let body = self.body.as_ref()?;
 325         let infer = self.infer.as_ref()?;
 326
 327         let expr_id = self.expr_id(db, &literal.clone().into())?;
 328         let substs = infer.type_of_expr[expr_id].as_adt()?.1;
 329
 330         let (variant, missing_fields, _exhaustive) =
 331             record_literal_missing_fields(db, infer, expr_id, &body[expr_id])?;
 332         let res = self.missing_fields(db, krate, substs, variant, missing_fields);
 333         Some(res)
 334     }
 335
 336     pub(crate) fn record_pattern_missing_fields(
 337         &self,
 338         db: &dyn HirDatabase,
 339         pattern: &ast::RecordPat,
 340     ) -> Option<Vec<(Field, Type)>> {
 341         let krate = self.resolver.krate()?;
 342         let body = self.body.as_ref()?;
 343         let infer = self.infer.as_ref()?;
 344
 345         let pat_id = self.pat_id(&pattern.clone().into())?;
 346         let substs = infer.type_of_pat[pat_id].as_adt()?.1;
 347
 348         let (variant, missing_fields, _exhaustive) =
 349             record_pattern_missing_fields(db, infer, pat_id, &body[pat_id])?;
 350         let res = self.missing_fields(db, krate, substs, variant, missing_fields);
 351         Some(res)
 352     }
 353
 354     fn missing_fields(
 355         &self,
 356         db: &dyn HirDatabase,
 357         krate: CrateId,
 358         substs: &Substitution,
 359         variant: VariantId,
 360         missing_fields: Vec<LocalFieldId>,
 361     ) -> Vec<(Field, Type)> {
 362         let field_types = db.field_types(variant);
 363
 364         missing_fields
 365             .into_iter()
 366             .map(|local_id| {
 367                 let field = FieldId { parent: variant, local_id };
 368                 let ty = field_types[local_id].clone().substitute(&Interner, substs);
 369                 (field.into(), Type::new_with_resolver_inner(db, krate, &self.resolver, ty))
 370             })
 371             .collect()
 372     }
 373
 374     pub(crate) fn expand(
 375         &self,
 376         db: &dyn HirDatabase,
 377         macro_call: InFile<&ast::MacroCall>,
 378     ) -> Option<HirFileId> {
 379         let krate = self.resolver.krate()?;
 380         let macro_call_id = macro_call.as_call_id(db.upcast(), krate, |path| {
 381             self.resolver.resolve_path_as_macro(db.upcast(), &path)
 382         })?;
 383         Some(macro_call_id.as_file()).filter(|it| it.expansion_level(db.upcast()) < 64)
 384     }
 385
 386     pub(crate) fn resolve_variant(
 387         &self,
 388         db: &dyn HirDatabase,
 389         record_lit: ast::RecordExpr,
 390     ) -> Option<VariantId> {
 391         let infer = self.infer.as_ref()?;
 392         let expr_id = self.expr_id(db, &record_lit.into())?;
 393         infer.variant_resolution_for_expr(expr_id)
 394     }
 395 }
 396
 397 fn scope_for(
 398     scopes: &ExprScopes,
 399     source_map: &BodySourceMap,
 400     node: InFile<&SyntaxNode>,
 401 ) -> Option<ScopeId> {
 402     node.value
 403         .ancestors()
 404         .filter_map(ast::Expr::cast)
 405         .filter_map(|it| source_map.node_expr(InFile::new(node.file_id, &it)))
 406         .find_map(|it| scopes.scope_for(it))
 407 }
 408
 409 fn scope_for_offset(
 410     db: &dyn HirDatabase,
 411     scopes: &ExprScopes,
 412     source_map: &BodySourceMap,
 413     offset: InFile<TextSize>,
 414 ) -> Option<ScopeId> {
 415     scopes
 416         .scope_by_expr()
 417         .iter()
 418         .filter_map(|(id, scope)| {
 419             let source = source_map.expr_syntax(*id).ok()?;
 420             // FIXME: correctly handle macro expansion
 421             if source.file_id != offset.file_id {
 422                 return None;
 423             }
 424             let root = source.file_syntax(db.upcast());
 425             let node = source.value.to_node(&root);
 426             Some((node.syntax().text_range(), scope))
 427         })
 428         // find containing scope
 429         .min_by_key(|(expr_range, _scope)| {
 430             (
 431                 !(expr_range.start() <= offset.value && offset.value <= expr_range.end()),
 432                 expr_range.len(),
 433             )
 434         })
 435         .map(|(expr_range, scope)| {
 436             adjust(db, scopes, source_map, expr_range, offset).unwrap_or(*scope)
 437         })
 438 }
 439
 440 // XXX: during completion, cursor might be outside of any particular
 441 // expression. Try to figure out the correct scope...
 442 fn adjust(
 443     db: &dyn HirDatabase,
 444     scopes: &ExprScopes,
 445     source_map: &BodySourceMap,
 446     expr_range: TextRange,
 447     offset: InFile<TextSize>,
 448 ) -> Option<ScopeId> {
 449     let child_scopes = scopes
 450         .scope_by_expr()
 451         .iter()
 452         .filter_map(|(id, scope)| {
 453             let source = source_map.expr_syntax(*id).ok()?;
 454             // FIXME: correctly handle macro expansion
 455             if source.file_id != offset.file_id {
 456                 return None;
 457             }
 458             let root = source.file_syntax(db.upcast());
 459             let node = source.value.to_node(&root);
 460             Some((node.syntax().text_range(), scope))
 461         })
 462         .filter(|&(range, _)| {
 463             range.start() <= offset.value && expr_range.contains_range(range) && range != expr_range
 464         });
 465
 466     child_scopes
 467         .max_by(|&(r1, _), &(r2, _)| {
 468             if r1.contains_range(r2) {
 469                 std::cmp::Ordering::Greater
 470             } else if r2.contains_range(r1) {
 471                 std::cmp::Ordering::Less
 472             } else {
 473                 r1.start().cmp(&r2.start())
 474             }
 475         })
 476         .map(|(_ptr, scope)| *scope)
 477 }
 478
 479 #[inline]
 480 pub(crate) fn resolve_hir_path(
 481     db: &dyn HirDatabase,
 482     resolver: &Resolver,
 483     path: &Path,
 484 ) -> Option<PathResolution> {
 485     resolve_hir_path_(db, resolver, path, false)
 486 }
 487
 488 fn resolve_hir_path_(
 489     db: &dyn HirDatabase,
 490     resolver: &Resolver,
 491     path: &Path,
 492     prefer_value_ns: bool,
 493 ) -> Option<PathResolution> {
 494     let types = || {
 495         let (ty, unresolved) = match path.type_anchor() {
 496             Some(type_ref) => {
 497                 let (_, res) = TyLoweringContext::new(db, resolver).lower_ty_ext(type_ref);
 498                 res.map(|ty_ns| (ty_ns, path.segments().first()))
 499             }
 500             None => {
 501                 let (ty, remaining) =
 502                     resolver.resolve_path_in_type_ns(db.upcast(), path.mod_path())?;
 503                 match remaining {
 504                     Some(remaining) if remaining > 1 => None,
 505                     _ => Some((ty, path.segments().get(1))),
 506                 }
 507             }
 508         }?;
 509         let res = match ty {
 510             TypeNs::SelfType(it) => PathResolution::SelfType(it.into()),
 511             TypeNs::GenericParam(id) => PathResolution::TypeParam(TypeParam { id }),
 512             TypeNs::AdtSelfType(it) | TypeNs::AdtId(it) => {
 513                 PathResolution::Def(Adt::from(it).into())
 514             }
 515             TypeNs::EnumVariantId(it) => PathResolution::Def(Variant::from(it).into()),
 516             TypeNs::TypeAliasId(it) => PathResolution::Def(TypeAlias::from(it).into()),
 517             TypeNs::BuiltinType(it) => PathResolution::Def(BuiltinType::from(it).into()),
 518             TypeNs::TraitId(it) => PathResolution::Def(Trait::from(it).into()),
 519         };
 520         match unresolved {
 521             Some(unresolved) => res
 522                 .assoc_type_shorthand_candidates(db, |name, alias| {
 523                     (name == unresolved.name).then(|| alias)
 524                 })
 525                 .map(TypeAlias::from)
 526                 .map(Into::into)
 527                 .map(PathResolution::Def),
 528             None => Some(res),
 529         }
 530     };
 531
 532     let body_owner = resolver.body_owner();
 533     let values = || {
 534         resolver.resolve_path_in_value_ns_fully(db.upcast(), path.mod_path()).and_then(|val| {
 535             let res = match val {
 536                 ValueNs::LocalBinding(pat_id) => {
 537                     let var = Local { parent: body_owner?, pat_id };
 538                     PathResolution::Local(var)
 539                 }
 540                 ValueNs::FunctionId(it) => PathResolution::Def(Function::from(it).into()),
 541                 ValueNs::ConstId(it) => PathResolution::Def(Const::from(it).into()),
 542                 ValueNs::StaticId(it) => PathResolution::Def(Static::from(it).into()),
 543                 ValueNs::StructId(it) => PathResolution::Def(Struct::from(it).into()),
 544                 ValueNs::EnumVariantId(it) => PathResolution::Def(Variant::from(it).into()),
 545                 ValueNs::ImplSelf(impl_id) => PathResolution::SelfType(impl_id.into()),
 546                 ValueNs::GenericParam(it) => PathResolution::ConstParam(it.into()),
 547             };
 548             Some(res)
 549         })
 550     };
 551
 552     let items = || {
 553         resolver
 554             .resolve_module_path_in_items(db.upcast(), path.mod_path())
 555             .take_types()
 556             .map(|it| PathResolution::Def(it.into()))
 557     };
 558
 559     let macros = || {
 560         resolver
 561             .resolve_path_as_macro(db.upcast(), path.mod_path())
 562             .map(|def| PathResolution::Macro(def.into()))
 563     };
 564
 565     if prefer_value_ns { values().or_else(types) } else { types().or_else(values) }
 566         .or_else(items)
 567         .or_else(macros)
 568 }
 569
 570 /// Resolves a path where we know it is a qualifier of another path.
 571 ///
 572 /// For example, if we have:
 573 /// ```
 574 /// mod my {
 575 ///     pub mod foo {
 576 ///         struct Bar;
 577 ///     }
 578 ///
 579 ///     pub fn foo() {}
 580 /// }
 581 /// ```
 582 /// then we know that `foo` in `my::foo::Bar` refers to the module, not the function.
 583 fn resolve_hir_path_qualifier(
 584     db: &dyn HirDatabase,
 585     resolver: &Resolver,
 586     path: &Path,
 587 ) -> Option<PathResolution> {
 588     let items = resolver
 589         .resolve_module_path_in_items(db.upcast(), path.mod_path())
 590         .take_types()
 591         .map(|it| PathResolution::Def(it.into()));
 592
 593     if items.is_some() {
 594         return items;
 595     }
 596
 597     resolver.resolve_path_in_type_ns_fully(db.upcast(), path.mod_path()).map(|ty| match ty {
 598         TypeNs::SelfType(it) => PathResolution::SelfType(it.into()),
 599         TypeNs::GenericParam(id) => PathResolution::TypeParam(TypeParam { id }),
 600         TypeNs::AdtSelfType(it) | TypeNs::AdtId(it) => PathResolution::Def(Adt::from(it).into()),
 601         TypeNs::EnumVariantId(it) => PathResolution::Def(Variant::from(it).into()),
 602         TypeNs::TypeAliasId(it) => PathResolution::Def(TypeAlias::from(it).into()),
 603         TypeNs::BuiltinType(it) => PathResolution::Def(BuiltinType::from(it).into()),
 604         TypeNs::TraitId(it) => PathResolution::Def(Trait::from(it).into()),
 605     })
 606 }