ClangCodeModel: Fix issue pane management for clangd diagnostics

We basically forgot to implement this. A task in the issues pane was
created for every text mark, but there was no code to deal with handling
editor switches, resulting in seemingly random behavior.

Fixes: QTCREATORBUG-27260
Change-Id: Ifcc1e04db4c37dde7e80f0e1646dc7c557cd7481
Reviewed-by: Qt CI Bot <qt_ci_bot@qt-project.org>
Reviewed-by: <github-actions-qt-creator@cristianadam.eu>
Reviewed-by: David Schulz <david.schulz@qt.io>

src/plugins/clangcodemodel/clangdclient.cpp

@@ -1285,6 +1285,7 @@ public:
 
     QHash<TextDocument *, HighlightingData> highlightingData;
     QHash<Utils::FilePath, CppEditor::BaseEditorDocumentParser::Configuration> parserConfigs;
+    QHash<Utils::FilePath, Tasks> issuePaneEntries;
 
     VersionedDataCache<const TextDocument *, AstNode> astCache;
     VersionedDataCache<Utils::FilePath, AstNode> externalAstCache;
@@ -1717,13 +1718,30 @@ const LanguageClient::Client::CustomInspectorTabs ClangdClient::createCustomInsp
 
 class ClangdDiagnosticManager : public LanguageClient::DiagnosticManager
 {
-public:
     using LanguageClient::DiagnosticManager::DiagnosticManager;
 
+    ClangdClient *getClient() const { return qobject_cast<ClangdClient *>(client()); }
+
+    bool isCurrentDocument(const Utils::FilePath &filePath) const
+    {
+        const IDocument * const doc = EditorManager::currentDocument();
+        return doc && doc->filePath() == filePath;
+    }
+
+    void showDiagnostics(const DocumentUri &uri, int version) override
+    {
+        const Utils::FilePath filePath = uri.toFilePath();
+        getClient()->clearTasks(filePath);
+        DiagnosticManager::showDiagnostics(uri, version);
+        if (isCurrentDocument(filePath))
+            getClient()->switchIssuePaneEntries(filePath);
+    }
+
     void hideDiagnostics(const Utils::FilePath &filePath) override
     {
         DiagnosticManager::hideDiagnostics(filePath);
-        TaskHub::clearTasks(Constants::TASK_CATEGORY_DIAGNOSTICS);
+        if (isCurrentDocument(filePath))
+            TaskHub::clearTasks(Constants::TASK_CATEGORY_DIAGNOSTICS);
     }
 
     QList<Diagnostic> filteredDiagnostics(const QList<Diagnostic> &diagnostics) const override
@@ -1739,7 +1757,7 @@ public:
                              const Diagnostic &diagnostic,
                              bool isProjectFile) const override
     {
-        return new ClangdTextMark(filePath, diagnostic, isProjectFile, client());
+        return new ClangdTextMark(filePath, diagnostic, isProjectFile, getClient());
     }
 };
 
@@ -1937,6 +1955,24 @@ void ClangdClient::updateParserConfig(const Utils::FilePath &filePath,
     sendContent(DidChangeConfigurationNotification(configChangeParams));
 }
 
+void ClangdClient::switchIssuePaneEntries(const Utils::FilePath &filePath)
+{
+    TaskHub::clearTasks(Constants::TASK_CATEGORY_DIAGNOSTICS);
+    const Tasks tasks = d->issuePaneEntries.value(filePath);
+    for (const Task &t : tasks)
+        TaskHub::addTask(t);
+}
+
+void ClangdClient::addTask(const ProjectExplorer::Task &task)
+{
+    d->issuePaneEntries[task.file] << task;
+}
+
+void ClangdClient::clearTasks(const Utils::FilePath &filePath)
+{
+    d->issuePaneEntries[filePath].clear();
+}
+
 void ClangdClient::Private::handleFindUsagesResult(quint64 key, const QList<Location> &locations)
 {
     const auto refData = runningFindUsages.find(key);

src/plugins/clangcodemodel/clangdclient.h

@@ -37,7 +37,10 @@
 namespace Core { class SearchResultItem; }
 namespace CppEditor { class CppEditorWidget; }
 namespace LanguageServerProtocol { class Range; }
-namespace ProjectExplorer { class Project; }
+namespace ProjectExplorer {
+class Project;
+class Task;
+}
 namespace TextEditor { class BaseTextEditor; }
 
 namespace ClangCodeModel {
@@ -93,6 +96,9 @@ public:
 
     void updateParserConfig(const Utils::FilePath &filePath,
                             const CppEditor::BaseEditorDocumentParser::Configuration &config);
+    void switchIssuePaneEntries(const Utils::FilePath &filePath);
+    void addTask(const ProjectExplorer::Task &task);
+    void clearTasks(const Utils::FilePath &filePath);
 
 signals:
     void indexingFinished();

src/plugins/clangcodemodel/clangmodelmanagersupport.cpp

@@ -282,8 +282,10 @@ void ClangModelManagerSupport::onCurrentEditorChanged(Core::IEditor *editor)
     const ::Utils::FilePath filePath = editor->document()->filePath();
     if (auto processor = ClangEditorDocumentProcessor::get(filePath.toString())) {
         processor->semanticRehighlight();
-        if (const auto client = clientForFile(filePath))
+        if (const auto client = clientForFile(filePath)) {
             client->updateParserConfig(filePath, processor->parserConfig());
+            client->switchIssuePaneEntries(filePath);
+        }
     }
 }
 

src/plugins/clangcodemodel/clangtextmark.cpp

@@ -39,7 +39,7 @@
 #include <cppeditor/cpptoolsreuse.h>
 #include <cppeditor/cppcodemodelsettings.h>
 
-#include <projectexplorer/taskhub.h>
+#include <projectexplorer/task.h>
 
 #include <utils/fadingindicator.h>
 #include <utils/qtcassert.h>
@@ -279,7 +279,7 @@ ClangDiagnostic convertDiagnostic(const ClangdDiagnostic &src, const FilePath &f
     return target;
 }
 
-void addTask(const ClangDiagnostic &diagnostic)
+Task createTask(const ClangDiagnostic &diagnostic)
 {
     Task::TaskType taskType = Task::TaskType::Unknown;
     QIcon icon;
@@ -298,13 +298,13 @@ void addTask(const ClangDiagnostic &diagnostic)
         break;
     }
 
-    TaskHub::addTask(Task(taskType,
-                          diagnosticCategoryPrefixRemoved(diagnostic.text),
-                          FilePath::fromString(diagnostic.location.targetFilePath.toString()),
-                          diagnostic.location.targetLine,
-                          Constants::TASK_CATEGORY_DIAGNOSTICS,
-                          icon,
-                          Task::NoOptions));
+    return Task(taskType,
+                diagnosticCategoryPrefixRemoved(diagnostic.text),
+                FilePath::fromString(diagnostic.location.targetFilePath.toString()),
+                diagnostic.location.targetLine,
+                Constants::TASK_CATEGORY_DIAGNOSTICS,
+                icon,
+                Task::NoOptions);
 }
 
 } // anonymous namespace
@@ -312,7 +312,7 @@ void addTask(const ClangDiagnostic &diagnostic)
 ClangdTextMark::ClangdTextMark(const FilePath &filePath,
                                const Diagnostic &diagnostic,
                                bool isProjectFile,
-                               const Client *client)
+                               Client *client)
     : TextEditor::TextMark(filePath, int(diagnostic.range().start().line() + 1), client->id())
     , m_lspDiagnostic(diagnostic)
     , m_diagnostic(convertDiagnostic(ClangdDiagnostic(diagnostic), filePath))
@@ -330,7 +330,7 @@ ClangdTextMark::ClangdTextMark(const FilePath &filePath,
         setLineAnnotation(diagnostic.message());
         setColor(isError ? Theme::CodeModel_Error_TextMarkColor
                          : Theme::CodeModel_Warning_TextMarkColor);
-        addTask(m_diagnostic);
+        qobject_cast<ClangdClient *>(client)->addTask(createTask(m_diagnostic));
     }
 
     // Copy to clipboard action

src/plugins/clangcodemodel/clangtextmark.h

@@ -47,7 +47,7 @@ public:
     ClangdTextMark(const ::Utils::FilePath &filePath,
                    const LanguageServerProtocol::Diagnostic &diagnostic,
                    bool isProjectFile,
-                   const LanguageClient::Client *client);
+                   LanguageClient::Client *client);
 
 private:
     bool addToolTipContent(QLayout *target) const override;