ClangCodeModel: Provide outline via clangd

Note that we used to encode the information about symbol visibility and
static-ness in the icons, which we can't do anymore, because clangd does
not provide this information.
On the upside, this change likely fixes a ton of bugs, as our own outline
was rather "quirky".

Change-Id: I099f11ec4e3c6f52cd461fb43080bbdde3bed5e5
Reviewed-by: David Schulz <david.schulz@qt.io>

src/plugins/clangcodemodel/clangdclient.cpp

@@ -732,6 +732,31 @@ ClangdClient::ClangdClient(Project *project, const Utils::FilePath &jsonDbDir)
     const auto hideDiagsHandler = []{ ClangDiagnosticManager::clearTaskHubIssues(); };
     setDiagnosticsHandlers(textMarkCreator, hideDiagsHandler);
 
+    static const auto symbolStringifier = [](SymbolKind kind, const QString &name,
+            const QString &detail) -> QString
+    {
+        switch (kind) {
+        case LanguageServerProtocol::SymbolKind::Constructor:
+            return name + detail;
+        case LanguageServerProtocol::SymbolKind::Method:
+        case LanguageServerProtocol::SymbolKind::Function: {
+            const int parenOffset = detail.indexOf(" (");
+            if (parenOffset == -1)
+                return name;
+            return name + detail.mid(parenOffset + 1) + " -> " + detail.mid(0, parenOffset);
+        }
+        case LanguageServerProtocol::SymbolKind::Variable:
+        case LanguageServerProtocol::SymbolKind::Field:
+        case LanguageServerProtocol::SymbolKind::Constant:
+            if (detail.isEmpty())
+                return name;
+            return name + " -> " + detail;
+        default:
+            return name;
+        }
+    };
+    setSymbolStringifier(symbolStringifier);
+
     hoverHandler()->setHelpItemProvider([this](const HoverRequest::Response &response,
                                                const DocumentUri &uri) {
         gatherHelpItemForTooltip(response, uri);

src/plugins/clangcodemodel/clangmodelmanagersupport.cpp

@@ -171,6 +171,11 @@ std::unique_ptr<CppTools::AbstractOverviewModel> ClangModelManagerSupport::creat
     return std::make_unique<OverviewModel>();
 }
 
+bool ClangModelManagerSupport::supportsOutline(const TextEditor::TextDocument *document) const
+{
+    return !clientForFile(document->filePath());
+}
+
 CppTools::BaseEditorDocumentProcessor *ClangModelManagerSupport::createEditorDocumentProcessor(
         TextEditor::TextDocument *baseTextDocument)
 {
@@ -344,7 +349,7 @@ void ClangModelManagerSupport::updateLanguageClient(ProjectExplorer::Project *pr
 }
 
 ClangdClient *ClangModelManagerSupport::clientForProject(
-        const ProjectExplorer::Project *project)
+        const ProjectExplorer::Project *project) const
 {
     const QList<Client *> clients = Utils::filtered(
                 LanguageClientManager::clientsForProject(project),
@@ -357,7 +362,7 @@ ClangdClient *ClangModelManagerSupport::clientForProject(
     return clients.empty() ? nullptr : qobject_cast<ClangdClient *>(clients.first());
 }
 
-ClangdClient *ClangModelManagerSupport::clientForFile(const Utils::FilePath &file)
+ClangdClient *ClangModelManagerSupport::clientForFile(const Utils::FilePath &file) const
 {
     return clientForProject(ProjectExplorer::SessionManager::projectForFile(file));
 }

src/plugins/clangcodemodel/clangmodelmanagersupport.h

@@ -72,6 +72,7 @@ public:
     CppTools::FollowSymbolInterface &followSymbolInterface() override;
     CppTools::RefactoringEngineInterface &refactoringEngineInterface() override;
     std::unique_ptr<CppTools::AbstractOverviewModel> createOverviewModel() override;
+    bool supportsOutline(const TextEditor::TextDocument *document) const override;
 
     BackendCommunicator &communicator();
     QString dummyUiHeaderOnDiskDirPath() const;
@@ -79,8 +80,8 @@ public:
 
     ClangProjectSettings &projectSettings(ProjectExplorer::Project *project) const;
 
-    ClangdClient *clientForProject(const ProjectExplorer::Project *project);
-    ClangdClient *clientForFile(const Utils::FilePath &file);
+    ClangdClient *clientForProject(const ProjectExplorer::Project *project) const;
+    ClangdClient *clientForFile(const Utils::FilePath &file) const;
 
     static ClangModelManagerSupport *instance();