Clang: Use built-in follow symbol for virtual methods

ClangCodeModel currently does not provide a list of overrides.
Therefore it makes sense to use ClangCodeModel result for
virtual method only if built-in code model does not find anything.

Task-number: QTCREATORBUG-20584
Change-Id: I5b4fac7974f990e741d3438ab61827670a8ce8d8
Reviewed-by: Nikolai Kosjar <nikolai.kosjar@qt.io>

src/libs/clangsupport/followsymbolmessage.cpp

@@ -33,7 +33,7 @@ QDebug operator<<(QDebug debug, const FollowSymbolResult &result)
 {
     debug.nospace() << "FollowSymbolResult("
                     << result.range
-                    << ", " << result.isPureDeclarationForUsage;
+                    << ", " << result.isResultOnlyForFallBack;
 
     debug.nospace() << ")";
 

src/libs/clangsupport/followsymbolmessage.h

@@ -40,15 +40,15 @@ public:
     FollowSymbolResult(SourceRangeContainer range)
         : range(std::move(range))
     {}
-    FollowSymbolResult(SourceRangeContainer range, bool isPureDeclarationForUsage)
+    FollowSymbolResult(SourceRangeContainer range, bool isResultOnlyForFallBack)
         : range(std::move(range))
-        , isPureDeclarationForUsage(isPureDeclarationForUsage)
+        , isResultOnlyForFallBack(isResultOnlyForFallBack)
     {}
 
     friend QDataStream &operator<<(QDataStream &out, const FollowSymbolResult &container)
     {
         out << container.range;
-        out << container.isPureDeclarationForUsage;
+        out << container.isResultOnlyForFallBack;
 
         return out;
     }
@@ -56,7 +56,7 @@ public:
     friend QDataStream &operator>>(QDataStream &in, FollowSymbolResult &container)
     {
         in >> container.range;
-        in >> container.isPureDeclarationForUsage;
+        in >> container.isResultOnlyForFallBack;
 
         return in;
     }
@@ -64,11 +64,11 @@ public:
     friend bool operator==(const FollowSymbolResult &first, const FollowSymbolResult &second)
     {
         return first.range == second.range
-                && first.isPureDeclarationForUsage == second.isPureDeclarationForUsage;
+                && first.isResultOnlyForFallBack == second.isResultOnlyForFallBack;
     }
 
     SourceRangeContainer range;
-    bool isPureDeclarationForUsage = false;
+    bool isResultOnlyForFallBack = false;
 };
 
 class FollowSymbolMessage

src/plugins/clangcodemodel/clangbackendreceiver.cpp

@@ -265,7 +265,7 @@ CppTools::SymbolInfo toSymbolInfo(const FollowSymbolMessage &message)
     result.endColumn = static_cast<int>(end.column);
     result.fileName = start.filePath;
 
-    result.isPureDeclarationForUsage = message.result.isPureDeclarationForUsage;
+    result.isResultOnlyForFallBack = message.result.isResultOnlyForFallBack;
 
     return result;
 }

src/plugins/clangcodemodel/clangfollowsymbol.cpp

@@ -145,7 +145,7 @@ static ::Utils::ProcessLinkCallback extendedCallback(::Utils::ProcessLinkCallbac
 {
     // If globalFollowSymbol finds nothing follow to the declaration.
     return [original_callback = std::move(callback), result](const ::Utils::Link &link) {
-        if (!link.hasValidTarget() && result.isPureDeclarationForUsage) {
+        if (link.linkTextStart < 0 && result.isResultOnlyForFallBack) {
             return original_callback(::Utils::Link(result.fileName, result.startLine,
                                           result.startColumn - 1));
         }
@@ -198,7 +198,7 @@ void ClangFollowSymbol::findLink(const CppTools::CursorInEditor &data,
             return callback(Utils::Link());
         CppTools::SymbolInfo result = m_watcher->result();
         // We did not fail but the result is empty
-        if (result.fileName.isEmpty() || result.isPureDeclarationForUsage) {
+        if (result.fileName.isEmpty() || result.isResultOnlyForFallBack) {
             const CppTools::RefactoringEngineInterface &refactoringEngine
                     = *CppTools::CppModelManager::instance();
             refactoringEngine.globalFollowSymbol(data,

src/plugins/cpptools/cppsymbolinfo.h

@@ -39,7 +39,7 @@ public:
     int endLine = 0;
     int endColumn = 0;
     QString fileName;
-    bool isPureDeclarationForUsage = false;
+    bool isResultOnlyForFallBack = false;
 };
 
 } // namespace CppTools

src/tools/clangbackend/source/clangfollowsymbol.cpp

@@ -152,14 +152,15 @@ FollowSymbolResult FollowSymbol::followSymbol(CXTranslationUnit tu,
     if (!cursor.isDeclaration()) {
         // This is the symbol usage
         // We want to return definition
-        FollowSymbolResult result;
         cursor = cursor.referenced();
         if (cursor.isNull())
             return SourceRangeContainer();
-        if (!cursor.isDefinition()) {
+
-            // We can't find definition in this TU
+        FollowSymbolResult result;
-            result.isPureDeclarationForUsage = true;
+        // We can't find definition in this TU or it's a virtual method call
-        }
+        if (!cursor.isDefinition() || cursor.isVirtualMethod())
+            result.isResultOnlyForFallBack = true;
+
         result.range = extractMatchingTokenRange(cursor, tokenSpelling);
         return result;
     }

tests/unit/unittest/gtest-creator-printing.cpp

@@ -241,7 +241,7 @@ std::ostream &operator<<(std::ostream &os, const FollowSymbolResult &result)
 {
     os << "("
        << result.range
-       << ", " << result.isPureDeclarationForUsage
+       << ", " << result.isResultOnlyForFallBack
        << ")";
 
     return os;