ClangCodeModel: Implement following a symbol to its type

Making use of LSP's "Go To Type Definition".
Just the backend for now, UI to follow.

Change-Id: Id73b2cf701eab03913477f6d4d3093e257e80dbd
Reviewed-by: David Schulz <david.schulz@qt.io>
Reviewed-by: Qt CI Bot <qt_ci_bot@qt-project.org>

src/plugins/clangcodemodel/clangdclient.cpp

@@ -822,6 +822,7 @@ void ClangdClient::followSymbol(TextDocument *document,
         CppEditor::CppEditorWidget *editorWidget,
         const Utils::LinkHandler &callback,
         bool resolveTarget,
+        FollowTo followTo,
         bool openInSplit
         )
 {
@@ -839,7 +840,7 @@ void ClangdClient::followSymbol(TextDocument *document,
     qCDebug(clangdLog) << "follow symbol requested" << document->filePath()
                        << adjustedCursor.blockNumber() << adjustedCursor.positionInBlock();
     d->followSymbol = new ClangdFollowSymbol(this, adjustedCursor, editorWidget, document, callback,
-                                             openInSplit);
+                                             followTo, openInSplit);
     connect(d->followSymbol, &ClangdFollowSymbol::done, this, [this] {
         d->followSymbol->deleteLater();
         d->followSymbol = nullptr;

src/plugins/clangcodemodel/clangdclient.h

@@ -34,6 +34,8 @@ Q_DECLARE_LOGGING_CATEGORY(clangdLogAst);
 
 void setupClangdConfigFile();
 
+enum class FollowTo { SymbolDef, SymbolType };
+
 class ClangdClient : public LanguageClient::Client
 {
     Q_OBJECT
@@ -55,6 +57,7 @@ public:
             CppEditor::CppEditorWidget *editorWidget,
             const Utils::LinkHandler &callback,
             bool resolveTarget,
+            FollowTo followTo,
             bool openInSplit);
 
     void switchDeclDef(TextEditor::TextDocument *document,

src/plugins/clangcodemodel/clangdfollowsymbol.cpp

@@ -83,6 +83,7 @@ public:
           docRevision(editorWidget ? editorWidget->textDocument()->document()->revision() : -1),
           openInSplit(openInSplit) {}
 
+    void goToTypeDefinition();
     void handleGotoDefinitionResult();
     void sendGotoImplementationRequest(const Utils::Link &link);
     void handleGotoImplementationResult(const GotoImplementationRequest::Response &response);
@@ -118,7 +119,7 @@ public:
 
 ClangdFollowSymbol::ClangdFollowSymbol(ClangdClient *client, const QTextCursor &cursor,
         CppEditorWidget *editorWidget, TextDocument *document, const LinkHandler &callback,
-        bool openInSplit)
+        FollowTo followTo, bool openInSplit)
     : QObject(client),
       d(new Private(this, client, cursor, editorWidget, document->filePath(), callback,
                     openInSplit))
@@ -133,6 +134,11 @@ ClangdFollowSymbol::ClangdFollowSymbol(ClangdClient *client, const QTextCursor &
     d->focusChangedConnection = connect(qApp, &QApplication::focusChanged,
                                         this, [this] { emitDone(); }, Qt::QueuedConnection);
 
+    if (followTo == FollowTo::SymbolType) {
+        d->goToTypeDefinition();
+        return;
+    }
+
     // Step 1: Follow the symbol via "Go to Definition". At the same time, request the
     //         AST node corresponding to the cursor position, so we can find out whether
     //         we have to look for overrides.
@@ -353,6 +359,30 @@ ClangdFollowSymbol::VirtualFunctionAssistProvider::createProcessor(const AssistI
             = new VirtualFunctionAssistProcessor(m_followSymbol);
 }
 
+void ClangdFollowSymbol::Private::goToTypeDefinition()
+{
+    GotoTypeDefinitionRequest req(TextDocumentPositionParams(TextDocumentIdentifier{uri},
+                                                             Position(cursor)));
+    req.setResponseCallback([sentinel = QPointer(q), this, reqId = req.id()]
+                            (const GotoTypeDefinitionRequest::Response &response) {
+        qCDebug(clangdLog) << "received go to type definition reply";
+        if (!sentinel)
+            return;
+        Link link;
+        if (const std::optional<GotoResult> &result = response.result()) {
+            if (const auto ploc = std::get_if<Location>(&*result)) {
+                link = {ploc->toLink()};
+            } else if (const auto plloc = std::get_if<QList<Location>>(&*result)) {
+                if (!plloc->empty())
+                    link = plloc->first().toLink();
+            }
+        }
+        q->emitDone(link);
+    });
+    client->sendMessage(req, ClangdClient::SendDocUpdates::Ignore);
+    qCDebug(clangdLog) << "sending go to type definition request";
+}
+
 void ClangdFollowSymbol::Private::handleGotoDefinitionResult()
 {
     QTC_ASSERT(defLink.hasValidTarget(), return);

src/plugins/clangcodemodel/clangdfollowsymbol.h

@@ -17,6 +17,7 @@ QT_END_NAMESPACE
 namespace ClangCodeModel::Internal {
 class ClangdAstNode;
 class ClangdClient;
+enum class FollowTo;
 
 class ClangdFollowSymbol : public QObject
 {
@@ -25,7 +26,7 @@ public:
     ClangdFollowSymbol(ClangdClient *client, const QTextCursor &cursor,
                        CppEditor::CppEditorWidget *editorWidget,
                        TextEditor::TextDocument *document, const Utils::LinkHandler &callback,
-                       bool openInSplit);
+                       FollowTo followTo, bool openInSplit);
     ~ClangdFollowSymbol();
     void clear();
 

src/plugins/clangcodemodel/clangdswitchdecldef.cpp

@@ -169,7 +169,7 @@ void ClangdSwitchDeclDef::Private::handleDeclDefSwitchReplies()
     const QTextCursor funcNameCursor = cursorForFunctionName(*functionNode);
     if (!funcNameCursor.isNull()) {
         client->followSymbol(document.data(), funcNameCursor, editorWidget, callback,
-                             true, false);
+                             true, FollowTo::SymbolDef, false);
     }
     q->emitDone();
 }

src/plugins/clangcodemodel/clangmodelmanagersupport.cpp

@@ -262,7 +262,7 @@ void ClangModelManagerSupport::followSymbol(const CppEditor::CursorInEditor &dat
     if (ClangdClient * const client = clientForFile(data.filePath());
             client && client->isFullyIndexed()) {
         client->followSymbol(data.textDocument(), data.cursor(), data.editorWidget(),
-                             processLinkCallback, resolveTarget, inNextSplit);
+                             processLinkCallback, resolveTarget, FollowTo::SymbolDef, inNextSplit);
         return;
     }
 

src/plugins/clangcodemodel/test/clangdtests.cpp

@@ -313,38 +313,50 @@ void ClangdTestFollowSymbol::test_data()
     QTest::addColumn<QString>("targetFile");
     QTest::addColumn<int>("targetLine");
     QTest::addColumn<int>("targetColumn");
+    QTest::addColumn<bool>("goToType");
 
-    QTest::newRow("on namespace") << "main.cpp" << 27 << 1 << "header.h" << 28 << 11;
+    QTest::newRow("on namespace") << "main.cpp" << 27 << 1 << "header.h" << 28 << 11 << false;
-    QTest::newRow("class ref") << "main.cpp" << 27 << 9 << "header.h" << 34 << 7;
+    QTest::newRow("class ref") << "main.cpp" << 27 << 9 << "header.h" << 34 << 7 << false;
-    QTest::newRow("forward decl (same file)") << "header.h" << 32 << 7 << "header.h" << 34 << 7;
+    QTest::newRow("forward decl (same file)") << "header.h" << 32 << 7 << "header.h" << 34 << 7
-    QTest::newRow("forward decl (different file") << "header.h" << 48 << 9 << "main.cpp" << 54 << 7;
+                                              << false;
-    QTest::newRow("class definition (same file)") << "header.h" << 34 << 7 << "header.h" << 32 << 7;
+    QTest::newRow("forward decl (different file") << "header.h" << 48 << 9 << "main.cpp" << 54 << 7
+                                                  << false;
+    QTest::newRow("class definition (same file)") << "header.h" << 34 << 7 << "header.h" << 32 << 7
+                                                  << false;
     QTest::newRow("class definition (different file)") << "main.cpp" << 54 << 7
-                                                       << "header.h" << 48 << 7;
+                                                       << "header.h" << 48 << 7  << false;
-    QTest::newRow("constructor decl") << "header.h" << 36 << 5 << "main.cpp" << 27 << 14;
+    QTest::newRow("constructor decl") << "header.h" << 36 << 5 << "main.cpp" << 27 << 14 << false;
-    QTest::newRow("constructor definition") << "main.cpp" << 27 << 14 << "header.h" << 36 << 5;
+    QTest::newRow("constructor definition") << "main.cpp" << 27 << 14 << "header.h" << 36 << 5
-    QTest::newRow("member ref") << "main.cpp" << 39 << 10 << "header.h" << 38 << 18;
+                                            << false;
-    QTest::newRow("union member ref") << "main.cpp" << 91 << 20 << "main.cpp" << 86 << 13;
+    QTest::newRow("member ref") << "main.cpp" << 39 << 10 << "header.h" << 38 << 18 << false;
-    QTest::newRow("member decl") << "header.h" << 38 << 18 << "header.h" << 38 << 18;
+    QTest::newRow("union member ref") << "main.cpp" << 91 << 20 << "main.cpp" << 86 << 13 << false;
-    QTest::newRow("function ref") << "main.cpp" << 66 << 12 << "main.cpp" << 35 << 5;
+    QTest::newRow("member decl") << "header.h" << 38 << 18 << "header.h" << 38 << 18 << false;
-    QTest::newRow("member function ref") << "main.cpp" << 42 << 12 << "main.cpp" << 49 << 21;
+    QTest::newRow("function ref") << "main.cpp" << 66 << 12 << "main.cpp" << 35 << 5 << false;
-    QTest::newRow("function with no def ref") << "main.cpp" << 43 << 5 << "header.h" << 59 << 5;
+    QTest::newRow("member function ref") << "main.cpp" << 42 << 12 << "main.cpp" << 49 << 21
-    QTest::newRow("function def") << "main.cpp" << 35 << 5 << "header.h" << 52 << 5;
+                                         << false;
-    QTest::newRow("member function def") << "main.cpp" << 49 << 21 << "header.h" << 43 << 9;
+    QTest::newRow("function with no def ref") << "main.cpp" << 43 << 5 << "header.h" << 59 << 5
-    QTest::newRow("member function decl") << "header.h" << 43 << 9 << "main.cpp" << 49 << 21;
+                                              << false;
-    QTest::newRow("include") << "main.cpp" << 25 << 13 << "header.h" << 1 << 1;
+    QTest::newRow("function def") << "main.cpp" << 35 << 5 << "header.h" << 52 << 5 << false;
-    QTest::newRow("local var") << "main.cpp" << 39 << 6 << "main.cpp" << 36 << 9;
+    QTest::newRow("member function def") << "main.cpp" << 49 << 21 << "header.h" << 43 << 9
-    QTest::newRow("alias") << "main.cpp" << 36 << 5 << "main.cpp" << 33 << 7;
+                                         << false;
-    QTest::newRow("static var") << "main.cpp" << 40 << 27 << "header.h" << 30 << 7;
+    QTest::newRow("member function decl") << "header.h" << 43 << 9 << "main.cpp" << 49 << 21
+                                          << false;
+    QTest::newRow("include") << "main.cpp" << 25 << 13 << "header.h" << 1 << 1 << false;
+    QTest::newRow("local var") << "main.cpp" << 39 << 6 << "main.cpp" << 36 << 9 << false;
+    QTest::newRow("alias") << "main.cpp" << 36 << 5 << "main.cpp" << 33 << 7 << false;
+    QTest::newRow("static var") << "main.cpp" << 40 << 27 << "header.h" << 30 << 7 << false;
     QTest::newRow("member function ref (other class)") << "main.cpp" << 62 << 39
-                                                       << "cursor.cpp" << 104 << 22;
+                                                       << "cursor.cpp" << 104 << 22 << false;
-    QTest::newRow("macro ref") << "main.cpp" << 66 << 43 << "header.h" << 27 << 9;
+    QTest::newRow("macro ref") << "main.cpp" << 66 << 43 << "header.h" << 27 << 9 << false;
-    QTest::newRow("on namespace 2") << "main.cpp" << 27 << 3 << "header.h" << 28 << 11;
+    QTest::newRow("on namespace 2") << "main.cpp" << 27 << 3 << "header.h" << 28 << 11 << false;
-    QTest::newRow("after namespace") << "main.cpp" << 27 << 7 << "header.h" << 28 << 11;
+    QTest::newRow("after namespace") << "main.cpp" << 27 << 7 << "header.h" << 28 << 11 << false;
-    QTest::newRow("operator def") << "main.cpp" << 76 << 13 << "main.cpp" << 72 << 9;
+    QTest::newRow("operator def") << "main.cpp" << 76 << 13 << "main.cpp" << 72 << 9 << false;
-    QTest::newRow("operator def 2") << "main.cpp" << 80 << 15 << "main.cpp" << 73 << 10;
+    QTest::newRow("operator def 2") << "main.cpp" << 80 << 15 << "main.cpp" << 73 << 10 << false;
-    QTest::newRow("operator decl") << "main.cpp" << 72 << 12 << "main.cpp" << 76 << 10;
+    QTest::newRow("operator decl") << "main.cpp" << 72 << 12 << "main.cpp" << 76 << 10 << false;
-    QTest::newRow("operator decl 2") << "main.cpp" << 73 << 12 << "main.cpp" << 80 << 11;
+    QTest::newRow("operator decl 2") << "main.cpp" << 73 << 12 << "main.cpp" << 80 << 11 << false;
+
+    QTest::newRow("go to typedef") << "main.cpp" << 100 << 19 << "main.cpp" << 33 << 7 << true;
+    QTest::newRow("go to type") << "main.cpp" << 101 << 19 << "main.cpp" << 69 << 7 << true;
 }
 
 void ClangdTestFollowSymbol::test()
@@ -355,6 +367,7 @@ void ClangdTestFollowSymbol::test()
     QFETCH(QString, targetFile);
     QFETCH(int, targetLine);
     QFETCH(int, targetColumn);
+    QFETCH(bool, goToType);
 
     TextEditor::TextDocument * const doc = document(sourceFile);
     QVERIFY(doc);
@@ -371,7 +384,8 @@ void ClangdTestFollowSymbol::test()
     QTextCursor cursor(doc->document());
     const int pos = Utils::Text::positionInText(doc->document(), sourceLine, sourceColumn);
     cursor.setPosition(pos);
-    client()->followSymbol(doc, cursor, nullptr, handler, true, false);
+    client()->followSymbol(doc, cursor, nullptr, handler, true,
+                           goToType ? FollowTo::SymbolType : FollowTo::SymbolDef, false);
     timer.start(10000);
     loop.exec();
     QVERIFY(timer.isActive());

src/plugins/clangcodemodel/test/data/follow-symbol/main.cpp

@@ -92,4 +92,10 @@ struct S {
         int i = 42;
         return i;
     }
+
+    YYY getYYY() const { return YYY(); }
+    Bar getBar() const { return Bar(); }
 };
+
+static const auto yyyVar = S().getYYY();
+static const auto barVar = S().getBar();