Clang: Process SymbolKind and SymbolTags with the indexer

We add the infrastructure to compute the SymbolKind and SymbolTags in the
indexer. Later we have to add more for templates, virtual functions etc..

Change-Id: I9203c5cfbfffed3065337292010de5fce5736453
Reviewed-by: Ivan Donchevskii <ivan.donchevskii@qt.io>

src/tools/clangrefactoringbackend/source/indexdataconsumer.cpp

@@ -28,6 +28,7 @@
 #include <clang/Basic/SourceLocation.h>
 #include <clang/Index/IndexSymbol.h>
 #include <clang/AST/Decl.h>
+#include <clang/AST/DeclVisitor.h>
 
 #include <llvm/ADT/ArrayRef.h>
 
@@ -56,6 +57,41 @@ SymbolType symbolType(clang::index::SymbolRoleSet roles)
     return SymbolType::None;
 }
 
+using SymbolKindAndTags = std::pair<SymbolKind, SymbolTags>;
+
+class IndexingDeclVisitor : public clang::ConstDeclVisitor<IndexingDeclVisitor, SymbolKindAndTags>
+{
+public:
+    SymbolKindAndTags VisitTagDecl(const clang::TagDecl *declaration)
+    {
+        SymbolKindAndTags result = {SymbolKind::Tag, {}};
+        switch (declaration->getTagKind()) {
+        case clang::TTK_Struct: result.second.push_back(SymbolTag::Struct); break;
+        case clang::TTK_Interface: result.second.push_back(SymbolTag::MsvcInterface); break;
+        case clang::TTK_Union: result.second.push_back(SymbolTag::Union); break;
+        case clang::TTK_Class: result.second.push_back(SymbolTag::Class); break;
+        case clang::TTK_Enum: result.second.push_back(SymbolTag::Enumeration); break;
+        }
+
+        return result;
+    }
+
+    SymbolKindAndTags VisitFunctionDecl(const clang::FunctionDecl*)
+    {
+        return {SymbolKind::Function, {}};
+    }
+
+    SymbolKindAndTags VisitVarDecl(const clang::VarDecl*)
+    {
+        return {SymbolKind::Variable, {}};
+    }
+};
+
+SymbolKindAndTags symbolKindAndTags(const clang::Decl *declaration)
+{
+    static IndexingDeclVisitor visitor;
+    return visitor.Visit(declaration);
+}
 }
 
 bool IndexDataConsumer::handleDeclOccurence(const clang::Decl *declaration,
@@ -78,9 +114,13 @@ bool IndexDataConsumer::handleDeclOccurence(const clang::Decl *declaration,
         if (found == m_symbolEntries.end()) {
             Utils::optional<Utils::PathString> usr = generateUSR(namedDeclaration);
             if (usr) {
+                auto  kindAndTags = symbolKindAndTags(declaration);
                 m_symbolEntries.emplace(std::piecewise_construct,
                                         std::forward_as_tuple(globalId),
-                                        std::forward_as_tuple(std::move(usr.value()), symbolName(namedDeclaration)));
+                                        std::forward_as_tuple(std::move(usr.value()),
+                                                              symbolName(namedDeclaration),
+                                                              kindAndTags.first,
+                                                              kindAndTags.second));
             }
         }