CppEditor: Fix race condition for highlighting of local usages

Starting a renaming action involves looking up local usages. In this
case, a different code path than normal updates the editor's extra
selections, in order to make sure that the occurrence to be edited is
rendered in a special way. We must therefore prevent the normal handler
from taking action, as it would overwrite abovementioned special
selection.

Change-Id: Ia811b49b3023a0a366a43a69cc01e6b2b370acb5
Reviewed-by: David Schulz <david.schulz@qt.io>

src/plugins/cppeditor/cppeditorwidget.cpp

@@ -805,6 +805,11 @@ bool CppEditorWidget::isSemanticInfoValid() const
     return isSemanticInfoValidExceptLocalUses() && d->m_lastSemanticInfo.localUsesUpdated;
 }
 
+bool CppEditorWidget::isRenaming() const
+{
+    return d->m_localRenaming.isActive();
+}
+
 SemanticInfo CppEditorWidget::semanticInfo() const
 {
     return d->m_lastSemanticInfo;

src/plugins/cppeditor/cppeditorwidget.h

@@ -60,6 +60,7 @@ public:
 
     bool isSemanticInfoValidExceptLocalUses() const;
     bool isSemanticInfoValid() const;
+    bool isRenaming() const;
 
     QSharedPointer<FunctionDeclDefLink> declDefLink() const;
     void applyDeclDefLinkChanges(bool jumpToMatch);

src/plugins/cppeditor/cppuseselectionsupdater.cpp

@@ -41,7 +41,7 @@ enum { updateUseSelectionsInternalInMs = 500 };
 namespace CppEditor {
 namespace Internal {
 
-CppUseSelectionsUpdater::CppUseSelectionsUpdater(TextEditor::TextEditorWidget *editorWidget)
+CppUseSelectionsUpdater::CppUseSelectionsUpdater(CppEditorWidget *editorWidget)
     : m_editorWidget(editorWidget)
 {
     m_timer.setSingleShot(true);
@@ -157,6 +157,10 @@ void CppUseSelectionsUpdater::onFindUsesFinished()
         emit finished(CppTools::SemanticInfo::LocalUseMap(), false);
         return;
     }
+    if (m_editorWidget->isRenaming()) {
+        emit finished({}, false);
+        return;
+    }
 
     processResults(m_runnerWatcher->result());
 

src/plugins/cppeditor/cppuseselectionsupdater.h

@@ -32,18 +32,18 @@
 #include <QTextEdit>
 #include <QTimer>
 
-namespace TextEditor { class TextEditorWidget; }
-
 namespace CppEditor {
 namespace Internal {
 
+class CppEditorWidget;
+
 class CppUseSelectionsUpdater : public QObject
 {
     Q_OBJECT
     Q_DISABLE_COPY(CppUseSelectionsUpdater)
 
 public:
-    explicit CppUseSelectionsUpdater(TextEditor::TextEditorWidget *editorWidget);
+    explicit CppUseSelectionsUpdater(CppEditorWidget *editorWidget);
     ~CppUseSelectionsUpdater() override;
 
     void scheduleUpdate();
@@ -73,7 +73,7 @@ private:
     void updateUnusedSelections(const CursorInfo::Ranges &selections);
 
 private:
-    TextEditor::TextEditorWidget *m_editorWidget;
+    CppEditorWidget * const m_editorWidget;
 
     QTimer m_timer;