| //===--- FindSymbols.cpp ------------------------------------*- C++-*------===// | 
 | // | 
 | // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. | 
 | // See https://llvm.org/LICENSE.txt for license information. | 
 | // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception | 
 | // | 
 | //===----------------------------------------------------------------------===// | 
 | #include "FindSymbols.h" | 
 |  | 
 | #include "AST.h" | 
 | #include "FuzzyMatch.h" | 
 | #include "ParsedAST.h" | 
 | #include "Quality.h" | 
 | #include "SourceCode.h" | 
 | #include "index/Index.h" | 
 | #include "support/Logger.h" | 
 | #include "clang/AST/DeclTemplate.h" | 
 | #include "clang/Index/IndexSymbol.h" | 
 | #include "llvm/ADT/ArrayRef.h" | 
 | #include "llvm/ADT/STLExtras.h" | 
 | #include "llvm/ADT/SmallVector.h" | 
 | #include "llvm/ADT/StringRef.h" | 
 | #include <limits> | 
 | #include <optional> | 
 | #include <tuple> | 
 |  | 
 | #define DEBUG_TYPE "FindSymbols" | 
 |  | 
 | namespace clang { | 
 | namespace clangd { | 
 |  | 
 | namespace { | 
 | using ScoredSymbolInfo = std::pair<float, SymbolInformation>; | 
 | struct ScoredSymbolGreater { | 
 |   bool operator()(const ScoredSymbolInfo &L, const ScoredSymbolInfo &R) { | 
 |     if (L.first != R.first) | 
 |       return L.first > R.first; | 
 |     return L.second.name < R.second.name; // Earlier name is better. | 
 |   } | 
 | }; | 
 |  | 
 | // Returns true if \p Query can be found as a sub-sequence inside \p Scope. | 
 | bool approximateScopeMatch(llvm::StringRef Scope, llvm::StringRef Query) { | 
 |   assert(Scope.empty() || Scope.ends_with("::")); | 
 |   assert(Query.empty() || Query.ends_with("::")); | 
 |   while (!Scope.empty() && !Query.empty()) { | 
 |     auto Colons = Scope.find("::"); | 
 |     assert(Colons != llvm::StringRef::npos); | 
 |  | 
 |     llvm::StringRef LeadingSpecifier = Scope.slice(0, Colons + 2); | 
 |     Scope = Scope.slice(Colons + 2, llvm::StringRef::npos); | 
 |     Query.consume_front(LeadingSpecifier); | 
 |   } | 
 |   return Query.empty(); | 
 | } | 
 |  | 
 | } // namespace | 
 |  | 
 | llvm::Expected<Location> indexToLSPLocation(const SymbolLocation &Loc, | 
 |                                             llvm::StringRef TUPath) { | 
 |   auto Path = URI::resolve(Loc.FileURI, TUPath); | 
 |   if (!Path) | 
 |     return error("Could not resolve path for file '{0}': {1}", Loc.FileURI, | 
 |                  Path.takeError()); | 
 |   Location L; | 
 |   L.uri = URIForFile::canonicalize(*Path, TUPath); | 
 |   Position Start, End; | 
 |   Start.line = Loc.Start.line(); | 
 |   Start.character = Loc.Start.column(); | 
 |   End.line = Loc.End.line(); | 
 |   End.character = Loc.End.column(); | 
 |   L.range = {Start, End}; | 
 |   return L; | 
 | } | 
 |  | 
 | llvm::Expected<Location> symbolToLocation(const Symbol &Sym, | 
 |                                           llvm::StringRef TUPath) { | 
 |   // Prefer the definition over e.g. a function declaration in a header | 
 |   return indexToLSPLocation( | 
 |       Sym.Definition ? Sym.Definition : Sym.CanonicalDeclaration, TUPath); | 
 | } | 
 |  | 
 | llvm::Expected<std::vector<SymbolInformation>> | 
 | getWorkspaceSymbols(llvm::StringRef Query, int Limit, | 
 |                     const SymbolIndex *const Index, llvm::StringRef HintPath) { | 
 |   std::vector<SymbolInformation> Result; | 
 |   if (!Index) | 
 |     return Result; | 
 |  | 
 |   // Lookup for qualified names are performed as: | 
 |   // - Exact namespaces are boosted by the index. | 
 |   // - Approximate matches are (sub-scope match) included via AnyScope logic. | 
 |   // - Non-matching namespaces (no sub-scope match) are post-filtered. | 
 |   auto Names = splitQualifiedName(Query); | 
 |  | 
 |   FuzzyFindRequest Req; | 
 |   Req.Query = std::string(Names.second); | 
 |  | 
 |   // FuzzyFind doesn't want leading :: qualifier. | 
 |   auto HasLeadingColons = Names.first.consume_front("::"); | 
 |   // Limit the query to specific namespace if it is fully-qualified. | 
 |   Req.AnyScope = !HasLeadingColons; | 
 |   // Boost symbols from desired namespace. | 
 |   if (HasLeadingColons || !Names.first.empty()) | 
 |     Req.Scopes = {std::string(Names.first)}; | 
 |   if (Limit) { | 
 |     Req.Limit = Limit; | 
 |     // If we are boosting a specific scope allow more results to be retrieved, | 
 |     // since some symbols from preferred namespaces might not make the cut. | 
 |     if (Req.AnyScope && !Req.Scopes.empty()) | 
 |       *Req.Limit *= 5; | 
 |   } | 
 |   TopN<ScoredSymbolInfo, ScoredSymbolGreater> Top( | 
 |       Req.Limit ? *Req.Limit : std::numeric_limits<size_t>::max()); | 
 |   FuzzyMatcher Filter(Req.Query); | 
 |  | 
 |   Index->fuzzyFind(Req, [HintPath, &Top, &Filter, AnyScope = Req.AnyScope, | 
 |                          ReqScope = Names.first](const Symbol &Sym) { | 
 |     llvm::StringRef Scope = Sym.Scope; | 
 |     // Fuzzyfind might return symbols from irrelevant namespaces if query was | 
 |     // not fully-qualified, drop those. | 
 |     if (AnyScope && !approximateScopeMatch(Scope, ReqScope)) | 
 |       return; | 
 |  | 
 |     auto Loc = symbolToLocation(Sym, HintPath); | 
 |     if (!Loc) { | 
 |       log("Workspace symbols: {0}", Loc.takeError()); | 
 |       return; | 
 |     } | 
 |  | 
 |     SymbolQualitySignals Quality; | 
 |     Quality.merge(Sym); | 
 |     SymbolRelevanceSignals Relevance; | 
 |     Relevance.Name = Sym.Name; | 
 |     Relevance.Query = SymbolRelevanceSignals::Generic; | 
 |     // If symbol and request scopes do not match exactly, apply a penalty. | 
 |     Relevance.InBaseClass = AnyScope && Scope != ReqScope; | 
 |     if (auto NameMatch = Filter.match(Sym.Name)) | 
 |       Relevance.NameMatch = *NameMatch; | 
 |     else { | 
 |       log("Workspace symbol: {0} didn't match query {1}", Sym.Name, | 
 |           Filter.pattern()); | 
 |       return; | 
 |     } | 
 |     Relevance.merge(Sym); | 
 |     auto QualScore = Quality.evaluateHeuristics(); | 
 |     auto RelScore = Relevance.evaluateHeuristics(); | 
 |     auto Score = evaluateSymbolAndRelevance(QualScore, RelScore); | 
 |     dlog("FindSymbols: {0}{1} = {2}\n{3}{4}\n", Sym.Scope, Sym.Name, Score, | 
 |          Quality, Relevance); | 
 |  | 
 |     SymbolInformation Info; | 
 |     Info.name = (Sym.Name + Sym.TemplateSpecializationArgs).str(); | 
 |     Info.kind = indexSymbolKindToSymbolKind(Sym.SymInfo.Kind); | 
 |     Info.location = *Loc; | 
 |     Scope.consume_back("::"); | 
 |     Info.containerName = Scope.str(); | 
 |  | 
 |     // Exposed score excludes fuzzy-match component, for client-side re-ranking. | 
 |     Info.score = Relevance.NameMatch > std::numeric_limits<float>::epsilon() | 
 |                      ? Score / Relevance.NameMatch | 
 |                      : QualScore; | 
 |     Top.push({Score, std::move(Info)}); | 
 |   }); | 
 |   for (auto &R : std::move(Top).items()) | 
 |     Result.push_back(std::move(R.second)); | 
 |   return Result; | 
 | } | 
 |  | 
 | namespace { | 
 | std::string getSymbolName(ASTContext &Ctx, const NamedDecl &ND) { | 
 |   // Print `MyClass(Category)` instead of `Category` and `MyClass()` instead | 
 |   // of `anonymous`. | 
 |   if (const auto *Container = dyn_cast<ObjCContainerDecl>(&ND)) | 
 |     return printObjCContainer(*Container); | 
 |   // Differentiate between class and instance methods: print `-foo` instead of | 
 |   // `foo` and `+sharedInstance` instead of `sharedInstance`. | 
 |   if (const auto *Method = dyn_cast<ObjCMethodDecl>(&ND)) { | 
 |     std::string Name; | 
 |     llvm::raw_string_ostream OS(Name); | 
 |  | 
 |     OS << (Method->isInstanceMethod() ? '-' : '+'); | 
 |     Method->getSelector().print(OS); | 
 |  | 
 |     OS.flush(); | 
 |     return Name; | 
 |   } | 
 |   return printName(Ctx, ND); | 
 | } | 
 |  | 
 | std::string getSymbolDetail(ASTContext &Ctx, const NamedDecl &ND) { | 
 |   PrintingPolicy P(Ctx.getPrintingPolicy()); | 
 |   P.SuppressScope = true; | 
 |   P.SuppressUnwrittenScope = true; | 
 |   P.AnonymousTagLocations = false; | 
 |   P.PolishForDeclaration = true; | 
 |   std::string Detail; | 
 |   llvm::raw_string_ostream OS(Detail); | 
 |   if (ND.getDescribedTemplateParams()) { | 
 |     OS << "template "; | 
 |   } | 
 |   if (const auto *VD = dyn_cast<ValueDecl>(&ND)) { | 
 |     // FIXME: better printing for dependent type | 
 |     if (isa<CXXConstructorDecl>(VD)) { | 
 |       std::string ConstructorType = VD->getType().getAsString(P); | 
 |       // Print constructor type as "(int)" instead of "void (int)". | 
 |       llvm::StringRef WithoutVoid = ConstructorType; | 
 |       WithoutVoid.consume_front("void "); | 
 |       OS << WithoutVoid; | 
 |     } else if (!isa<CXXDestructorDecl>(VD)) { | 
 |       VD->getType().print(OS, P); | 
 |     } | 
 |   } else if (const auto *TD = dyn_cast<TagDecl>(&ND)) { | 
 |     OS << TD->getKindName(); | 
 |   } else if (isa<TypedefNameDecl>(&ND)) { | 
 |     OS << "type alias"; | 
 |   } else if (isa<ConceptDecl>(&ND)) { | 
 |     OS << "concept"; | 
 |   } | 
 |   return std::move(OS.str()); | 
 | } | 
 |  | 
 | std::optional<DocumentSymbol> declToSym(ASTContext &Ctx, const NamedDecl &ND) { | 
 |   auto &SM = Ctx.getSourceManager(); | 
 |  | 
 |   SourceLocation BeginLoc = SM.getFileLoc(ND.getBeginLoc()); | 
 |   SourceLocation EndLoc = SM.getFileLoc(ND.getEndLoc()); | 
 |   const auto SymbolRange = | 
 |       toHalfOpenFileRange(SM, Ctx.getLangOpts(), {BeginLoc, EndLoc}); | 
 |   if (!SymbolRange) | 
 |     return std::nullopt; | 
 |  | 
 |   index::SymbolInfo SymInfo = index::getSymbolInfo(&ND); | 
 |   // FIXME: This is not classifying constructors, destructors and operators | 
 |   // correctly. | 
 |   SymbolKind SK = indexSymbolKindToSymbolKind(SymInfo.Kind); | 
 |  | 
 |   DocumentSymbol SI; | 
 |   SI.name = getSymbolName(Ctx, ND); | 
 |   SI.kind = SK; | 
 |   SI.deprecated = ND.isDeprecated(); | 
 |   SI.range = Range{sourceLocToPosition(SM, SymbolRange->getBegin()), | 
 |                    sourceLocToPosition(SM, SymbolRange->getEnd())}; | 
 |   SI.detail = getSymbolDetail(Ctx, ND); | 
 |  | 
 |   SourceLocation NameLoc = ND.getLocation(); | 
 |   SourceLocation FallbackNameLoc; | 
 |   if (NameLoc.isMacroID()) { | 
 |     if (isSpelledInSource(NameLoc, SM)) { | 
 |       // Prefer the spelling loc, but save the expansion loc as a fallback. | 
 |       FallbackNameLoc = SM.getExpansionLoc(NameLoc); | 
 |       NameLoc = SM.getSpellingLoc(NameLoc); | 
 |     } else { | 
 |       NameLoc = SM.getExpansionLoc(NameLoc); | 
 |     } | 
 |   } | 
 |   auto ComputeSelectionRange = [&](SourceLocation L) -> Range { | 
 |     Position NameBegin = sourceLocToPosition(SM, L); | 
 |     Position NameEnd = sourceLocToPosition( | 
 |         SM, Lexer::getLocForEndOfToken(L, 0, SM, Ctx.getLangOpts())); | 
 |     return Range{NameBegin, NameEnd}; | 
 |   }; | 
 |  | 
 |   SI.selectionRange = ComputeSelectionRange(NameLoc); | 
 |   if (!SI.range.contains(SI.selectionRange) && FallbackNameLoc.isValid()) { | 
 |     // 'selectionRange' must be contained in 'range'. In cases where clang | 
 |     // reports unrelated ranges, we first try falling back to the expansion | 
 |     // loc for the selection range. | 
 |     SI.selectionRange = ComputeSelectionRange(FallbackNameLoc); | 
 |   } | 
 |   if (!SI.range.contains(SI.selectionRange)) { | 
 |     // If the containment relationship still doesn't hold, throw away | 
 |     // 'range' and use 'selectionRange' for both. | 
 |     SI.range = SI.selectionRange; | 
 |   } | 
 |   return SI; | 
 | } | 
 |  | 
 | /// A helper class to build an outline for the parse AST. It traverses the AST | 
 | /// directly instead of using RecursiveASTVisitor (RAV) for three main reasons: | 
 | ///    - there is no way to keep RAV from traversing subtrees we are not | 
 | ///      interested in. E.g. not traversing function locals or implicit template | 
 | ///      instantiations. | 
 | ///    - it's easier to combine results of recursive passes, | 
 | ///    - visiting decls is actually simple, so we don't hit the complicated | 
 | ///      cases that RAV mostly helps with (types, expressions, etc.) | 
 | class DocumentOutline { | 
 |   // A DocumentSymbol we're constructing. | 
 |   // We use this instead of DocumentSymbol directly so that we can keep track | 
 |   // of the nodes we insert for macros. | 
 |   class SymBuilder { | 
 |     std::vector<SymBuilder> Children; | 
 |     DocumentSymbol Symbol; // Symbol.children is empty, use Children instead. | 
 |     // Macro expansions that this node or its parents are associated with. | 
 |     // (Thus we will never create further children for these expansions). | 
 |     llvm::SmallVector<SourceLocation> EnclosingMacroLoc; | 
 |  | 
 |   public: | 
 |     DocumentSymbol build() && { | 
 |       for (SymBuilder &C : Children) { | 
 |         Symbol.children.push_back(std::move(C).build()); | 
 |         // Expand range to ensure children nest properly, which editors expect. | 
 |         // This can fix some edge-cases in the AST, but is vital for macros. | 
 |         // A macro expansion "contains" AST node if it covers the node's primary | 
 |         // location, but it may not span the node's whole range. | 
 |         Symbol.range.start = | 
 |             std::min(Symbol.range.start, Symbol.children.back().range.start); | 
 |         Symbol.range.end = | 
 |             std::max(Symbol.range.end, Symbol.children.back().range.end); | 
 |       } | 
 |       return std::move(Symbol); | 
 |     } | 
 |  | 
 |     // Add a symbol as a child of the current one. | 
 |     SymBuilder &addChild(DocumentSymbol S) { | 
 |       Children.emplace_back(); | 
 |       Children.back().EnclosingMacroLoc = EnclosingMacroLoc; | 
 |       Children.back().Symbol = std::move(S); | 
 |       return Children.back(); | 
 |     } | 
 |  | 
 |     // Get an appropriate container for children of this symbol that were | 
 |     // expanded from a macro (whose spelled name is Tok). | 
 |     // | 
 |     // This may return: | 
 |     //  - a macro symbol child of this (either new or previously created) | 
 |     //  - this scope itself, if it *is* the macro symbol or is nested within it | 
 |     SymBuilder &inMacro(const syntax::Token &Tok, const SourceManager &SM, | 
 |                         std::optional<syntax::TokenBuffer::Expansion> Exp) { | 
 |       if (llvm::is_contained(EnclosingMacroLoc, Tok.location())) | 
 |         return *this; | 
 |       // If there's an existing child for this macro, we expect it to be last. | 
 |       if (!Children.empty() && !Children.back().EnclosingMacroLoc.empty() && | 
 |           Children.back().EnclosingMacroLoc.back() == Tok.location()) | 
 |         return Children.back(); | 
 |  | 
 |       DocumentSymbol Sym; | 
 |       Sym.name = Tok.text(SM).str(); | 
 |       Sym.kind = SymbolKind::Null; // There's no suitable kind! | 
 |       Sym.range = Sym.selectionRange = | 
 |           halfOpenToRange(SM, Tok.range(SM).toCharRange(SM)); | 
 |  | 
 |       // FIXME: Exp is currently unavailable for nested expansions. | 
 |       if (Exp) { | 
 |         // Full range covers the macro args. | 
 |         Sym.range = halfOpenToRange(SM, CharSourceRange::getCharRange( | 
 |                                             Exp->Spelled.front().location(), | 
 |                                             Exp->Spelled.back().endLocation())); | 
 |         // Show macro args as detail. | 
 |         llvm::raw_string_ostream OS(Sym.detail); | 
 |         const syntax::Token *Prev = nullptr; | 
 |         for (const auto &Tok : Exp->Spelled.drop_front()) { | 
 |           // Don't dump arbitrarily long macro args. | 
 |           if (OS.tell() > 80) { | 
 |             OS << " ...)"; | 
 |             break; | 
 |           } | 
 |           if (Prev && Prev->endLocation() != Tok.location()) | 
 |             OS << ' '; | 
 |           OS << Tok.text(SM); | 
 |           Prev = &Tok; | 
 |         } | 
 |       } | 
 |       SymBuilder &Child = addChild(std::move(Sym)); | 
 |       Child.EnclosingMacroLoc.push_back(Tok.location()); | 
 |       return Child; | 
 |     } | 
 |   }; | 
 |  | 
 | public: | 
 |   DocumentOutline(ParsedAST &AST) : AST(AST) {} | 
 |  | 
 |   /// Builds the document outline for the generated AST. | 
 |   std::vector<DocumentSymbol> build() { | 
 |     SymBuilder Root; | 
 |     for (auto &TopLevel : AST.getLocalTopLevelDecls()) | 
 |       traverseDecl(TopLevel, Root); | 
 |     return std::move(std::move(Root).build().children); | 
 |   } | 
 |  | 
 | private: | 
 |   enum class VisitKind { No, OnlyDecl, OnlyChildren, DeclAndChildren }; | 
 |  | 
 |   void traverseDecl(Decl *D, SymBuilder &Parent) { | 
 |     // Skip symbols which do not originate from the main file. | 
 |     if (!isInsideMainFile(D->getLocation(), AST.getSourceManager())) | 
 |       return; | 
 |  | 
 |     if (auto *Templ = llvm::dyn_cast<TemplateDecl>(D)) { | 
 |       // TemplatedDecl might be null, e.g. concepts. | 
 |       if (auto *TD = Templ->getTemplatedDecl()) | 
 |         D = TD; | 
 |     } | 
 |  | 
 |     VisitKind Visit = shouldVisit(D); | 
 |     if (Visit == VisitKind::No) | 
 |       return; | 
 |  | 
 |     if (Visit == VisitKind::OnlyChildren) | 
 |       return traverseChildren(D, Parent); | 
 |  | 
 |     auto *ND = llvm::cast<NamedDecl>(D); | 
 |     auto Sym = declToSym(AST.getASTContext(), *ND); | 
 |     if (!Sym) | 
 |       return; | 
 |     SymBuilder &MacroParent = possibleMacroContainer(D->getLocation(), Parent); | 
 |     SymBuilder &Child = MacroParent.addChild(std::move(*Sym)); | 
 |  | 
 |     if (Visit == VisitKind::OnlyDecl) | 
 |       return; | 
 |  | 
 |     assert(Visit == VisitKind::DeclAndChildren && "Unexpected VisitKind"); | 
 |     traverseChildren(ND, Child); | 
 |   } | 
 |  | 
 |   // Determines where a decl should appear in the DocumentSymbol hierarchy. | 
 |   // | 
 |   // This is usually a direct child of the relevant AST parent. | 
 |   // But we may also insert nodes for macros. Given: | 
 |   //   #define DECLARE_INT(V) int v; | 
 |   //   namespace a { DECLARE_INT(x) } | 
 |   // We produce: | 
 |   //   Namespace a | 
 |   //     Macro DECLARE_INT(x) | 
 |   //       Variable x | 
 |   // | 
 |   // In the absence of macros, this method simply returns Parent. | 
 |   // Otherwise it may return a macro expansion node instead. | 
 |   // Each macro only has at most one node in the hierarchy, even if it expands | 
 |   // to multiple decls. | 
 |   SymBuilder &possibleMacroContainer(SourceLocation TargetLoc, | 
 |                                      SymBuilder &Parent) { | 
 |     const auto &SM = AST.getSourceManager(); | 
 |     // Look at the path of macro-callers from the token to the main file. | 
 |     // Note that along these paths we see the "outer" macro calls first. | 
 |     SymBuilder *CurParent = &Parent; | 
 |     for (SourceLocation Loc = TargetLoc; Loc.isMacroID(); | 
 |          Loc = SM.getImmediateMacroCallerLoc(Loc)) { | 
 |       // Find the virtual macro body that our token is being substituted into. | 
 |       FileID MacroBody; | 
 |       if (SM.isMacroArgExpansion(Loc)) { | 
 |         // Loc is part of a macro arg being substituted into a macro body. | 
 |         MacroBody = SM.getFileID(SM.getImmediateExpansionRange(Loc).getBegin()); | 
 |       } else { | 
 |         // Loc is already in the macro body. | 
 |         MacroBody = SM.getFileID(Loc); | 
 |       } | 
 |       // The macro body is being substituted for a macro expansion, whose | 
 |       // first token is the name of the macro. | 
 |       SourceLocation MacroName = | 
 |           SM.getSLocEntry(MacroBody).getExpansion().getExpansionLocStart(); | 
 |       // Only include the macro expansion in the outline if it was written | 
 |       // directly in the main file, rather than expanded from another macro. | 
 |       if (!MacroName.isValid() || !MacroName.isFileID()) | 
 |         continue; | 
 |       // All conditions satisfied, add the macro. | 
 |       if (auto *Tok = AST.getTokens().spelledTokenAt(MacroName)) | 
 |         CurParent = &CurParent->inMacro( | 
 |             *Tok, SM, AST.getTokens().expansionStartingAt(Tok)); | 
 |     } | 
 |     return *CurParent; | 
 |   } | 
 |  | 
 |   void traverseChildren(Decl *D, SymBuilder &Builder) { | 
 |     auto *Scope = llvm::dyn_cast<DeclContext>(D); | 
 |     if (!Scope) | 
 |       return; | 
 |     for (auto *C : Scope->decls()) | 
 |       traverseDecl(C, Builder); | 
 |   } | 
 |  | 
 |   VisitKind shouldVisit(Decl *D) { | 
 |     if (D->isImplicit()) | 
 |       return VisitKind::No; | 
 |  | 
 |     if (llvm::isa<LinkageSpecDecl>(D) || llvm::isa<ExportDecl>(D)) | 
 |       return VisitKind::OnlyChildren; | 
 |  | 
 |     if (!llvm::isa<NamedDecl>(D)) | 
 |       return VisitKind::No; | 
 |  | 
 |     if (auto *Func = llvm::dyn_cast<FunctionDecl>(D)) { | 
 |       // Some functions are implicit template instantiations, those should be | 
 |       // ignored. | 
 |       if (auto *Info = Func->getTemplateSpecializationInfo()) { | 
 |         if (!Info->isExplicitInstantiationOrSpecialization()) | 
 |           return VisitKind::No; | 
 |       } | 
 |       // Only visit the function itself, do not visit the children (i.e. | 
 |       // function parameters, etc.) | 
 |       return VisitKind::OnlyDecl; | 
 |     } | 
 |     // Handle template instantiations. We have three cases to consider: | 
 |     //   - explicit instantiations, e.g. 'template class std::vector<int>;' | 
 |     //     Visit the decl itself (it's present in the code), but not the | 
 |     //     children. | 
 |     //   - implicit instantiations, i.e. not written by the user. | 
 |     //     Do not visit at all, they are not present in the code. | 
 |     //   - explicit specialization, e.g. 'template <> class vector<bool> {};' | 
 |     //     Visit both the decl and its children, both are written in the code. | 
 |     if (auto *TemplSpec = llvm::dyn_cast<ClassTemplateSpecializationDecl>(D)) { | 
 |       if (TemplSpec->isExplicitInstantiationOrSpecialization()) | 
 |         return TemplSpec->isExplicitSpecialization() | 
 |                    ? VisitKind::DeclAndChildren | 
 |                    : VisitKind::OnlyDecl; | 
 |       return VisitKind::No; | 
 |     } | 
 |     if (auto *TemplSpec = llvm::dyn_cast<VarTemplateSpecializationDecl>(D)) { | 
 |       if (TemplSpec->isExplicitInstantiationOrSpecialization()) | 
 |         return TemplSpec->isExplicitSpecialization() | 
 |                    ? VisitKind::DeclAndChildren | 
 |                    : VisitKind::OnlyDecl; | 
 |       return VisitKind::No; | 
 |     } | 
 |     // For all other cases, visit both the children and the decl. | 
 |     return VisitKind::DeclAndChildren; | 
 |   } | 
 |  | 
 |   ParsedAST &AST; | 
 | }; | 
 |  | 
 | struct PragmaMarkSymbol { | 
 |   DocumentSymbol DocSym; | 
 |   bool IsGroup; | 
 | }; | 
 |  | 
 | /// Merge in `PragmaMarkSymbols`, sorted ascending by range, into the given | 
 | /// `DocumentSymbol` tree. | 
 | void mergePragmas(DocumentSymbol &Root, ArrayRef<PragmaMarkSymbol> Pragmas) { | 
 |   while (!Pragmas.empty()) { | 
 |     // We'll figure out where the Pragmas.front() should go. | 
 |     PragmaMarkSymbol P = std::move(Pragmas.front()); | 
 |     Pragmas = Pragmas.drop_front(); | 
 |     DocumentSymbol *Cur = &Root; | 
 |     while (Cur->range.contains(P.DocSym.range)) { | 
 |       bool Swapped = false; | 
 |       for (auto &C : Cur->children) { | 
 |         // We assume at most 1 child can contain the pragma (as pragmas are on | 
 |         // a single line, and children have disjoint ranges). | 
 |         if (C.range.contains(P.DocSym.range)) { | 
 |           Cur = &C; | 
 |           Swapped = true; | 
 |           break; | 
 |         } | 
 |       } | 
 |       // Cur is the parent of P since none of the children contain P. | 
 |       if (!Swapped) | 
 |         break; | 
 |     } | 
 |     // Pragma isn't a group so we can just insert it and we are done. | 
 |     if (!P.IsGroup) { | 
 |       Cur->children.emplace_back(std::move(P.DocSym)); | 
 |       continue; | 
 |     } | 
 |     // Pragma is a group, so we need to figure out where it terminates: | 
 |     // - If the next Pragma is not contained in Cur, P owns all of its | 
 |     //   parent's children which occur after P. | 
 |     // - If the next pragma is contained in Cur but actually belongs to one | 
 |     //   of the parent's children, we temporarily skip over it and look at | 
 |     //   the next pragma to decide where we end. | 
 |     // - Otherwise nest all of its parent's children which occur after P but | 
 |     //   before the next pragma. | 
 |     bool TerminatedByNextPragma = false; | 
 |     for (auto &NextPragma : Pragmas) { | 
 |       // If we hit a pragma outside of Cur, the rest will be outside as well. | 
 |       if (!Cur->range.contains(NextPragma.DocSym.range)) | 
 |         break; | 
 |  | 
 |       // NextPragma cannot terminate P if it is nested inside a child, look for | 
 |       // the next one. | 
 |       if (llvm::any_of(Cur->children, [&NextPragma](const auto &Child) { | 
 |             return Child.range.contains(NextPragma.DocSym.range); | 
 |           })) | 
 |         continue; | 
 |  | 
 |       // Pragma owns all the children between P and NextPragma | 
 |       auto It = llvm::partition(Cur->children, | 
 |                                 [&P, &NextPragma](const auto &S) -> bool { | 
 |                                   return !(P.DocSym.range < S.range && | 
 |                                            S.range < NextPragma.DocSym.range); | 
 |                                 }); | 
 |       P.DocSym.children.assign(make_move_iterator(It), | 
 |                                make_move_iterator(Cur->children.end())); | 
 |       Cur->children.erase(It, Cur->children.end()); | 
 |       TerminatedByNextPragma = true; | 
 |       break; | 
 |     } | 
 |     if (!TerminatedByNextPragma) { | 
 |       // P is terminated by the end of current symbol, hence it owns all the | 
 |       // children after P. | 
 |       auto It = llvm::partition(Cur->children, [&P](const auto &S) -> bool { | 
 |         return !(P.DocSym.range < S.range); | 
 |       }); | 
 |       P.DocSym.children.assign(make_move_iterator(It), | 
 |                                make_move_iterator(Cur->children.end())); | 
 |       Cur->children.erase(It, Cur->children.end()); | 
 |     } | 
 |     // Update the range for P to cover children and append to Cur. | 
 |     for (DocumentSymbol &Sym : P.DocSym.children) | 
 |       unionRanges(P.DocSym.range, Sym.range); | 
 |     Cur->children.emplace_back(std::move(P.DocSym)); | 
 |   } | 
 | } | 
 |  | 
 | PragmaMarkSymbol markToSymbol(const PragmaMark &P) { | 
 |   StringRef Name = StringRef(P.Trivia).trim(); | 
 |   bool IsGroup = false; | 
 |   // "-\s+<group name>" or "<name>" after an initial trim. The former is | 
 |   // considered a group, the latter just a mark. Like Xcode, we don't consider | 
 |   // `-Foo` to be a group (space(s) after the `-` is required). | 
 |   // | 
 |   // We need to include a name here, otherwise editors won't properly render the | 
 |   // symbol. | 
 |   StringRef MaybeGroupName = Name; | 
 |   if (MaybeGroupName.consume_front("-") && | 
 |       (MaybeGroupName.ltrim() != MaybeGroupName || MaybeGroupName.empty())) { | 
 |     Name = MaybeGroupName.empty() ? "(unnamed group)" : MaybeGroupName.ltrim(); | 
 |     IsGroup = true; | 
 |   } else if (Name.empty()) { | 
 |     Name = "(unnamed mark)"; | 
 |   } | 
 |   DocumentSymbol Sym; | 
 |   Sym.name = Name.str(); | 
 |   Sym.kind = SymbolKind::File; | 
 |   Sym.range = P.Rng; | 
 |   Sym.selectionRange = P.Rng; | 
 |   return {Sym, IsGroup}; | 
 | } | 
 |  | 
 | std::vector<DocumentSymbol> collectDocSymbols(ParsedAST &AST) { | 
 |   std::vector<DocumentSymbol> Syms = DocumentOutline(AST).build(); | 
 |  | 
 |   const auto &PragmaMarks = AST.getMarks(); | 
 |   if (PragmaMarks.empty()) | 
 |     return Syms; | 
 |  | 
 |   std::vector<PragmaMarkSymbol> Pragmas; | 
 |   Pragmas.reserve(PragmaMarks.size()); | 
 |   for (const auto &P : PragmaMarks) | 
 |     Pragmas.push_back(markToSymbol(P)); | 
 |   Range EntireFile = { | 
 |       {0, 0}, | 
 |       {std::numeric_limits<int>::max(), std::numeric_limits<int>::max()}}; | 
 |   DocumentSymbol Root; | 
 |   Root.children = std::move(Syms); | 
 |   Root.range = EntireFile; | 
 |   mergePragmas(Root, llvm::ArrayRef(Pragmas)); | 
 |   return Root.children; | 
 | } | 
 |  | 
 | } // namespace | 
 |  | 
 | llvm::Expected<std::vector<DocumentSymbol>> getDocumentSymbols(ParsedAST &AST) { | 
 |   return collectDocSymbols(AST); | 
 | } | 
 |  | 
 | } // namespace clangd | 
 | } // namespace clang |