4 files changed, 35 insertions, 22 deletions

diff --git a/src/plugins/texteditor/refactoringchanges.cpp b/src/plugins/texteditor/refactoringchanges.cpp
index 01c61f10f8..9e91463349 100644
--- a/src/plugins/texteditor/refactoringchanges.cpp
+++ b/src/plugins/texteditor/refactoringchanges.cpp
@@ -132,7 +132,7 @@ TextEditorWidget *RefactoringChanges::openEditor(const QString &fileName, bool a
     IEditor *editor = EditorManager::openEditorAt(fileName, line, column, Id(), flags);
 
     if (editor)
-        return qobject_cast<TextEditorWidget *>(editor->widget());
+        return TextEditorWidget::fromEditor(editor);
     else
         return nullptr;
 }
@@ -163,7 +163,7 @@ RefactoringFile::RefactoringFile(const QString &fileName, const QSharedPointer<R
 {
     QList<IEditor *> editors = DocumentModel::editorsForFilePath(fileName);
     if (!editors.isEmpty()) {
-        auto editorWidget = qobject_cast<TextEditorWidget *>(editors.first()->widget());
+        auto editorWidget = TextEditorWidget::fromEditor(editors.first());
         if (editorWidget && !editorWidget->isReadOnly())
             m_editor = editorWidget;
     }
diff --git a/src/plugins/texteditor/texteditor.cpp b/src/plugins/texteditor/texteditor.cpp
index 7e92bc24eb..635acd6e66 100644
--- a/src/plugins/texteditor/texteditor.cpp
+++ b/src/plugins/texteditor/texteditor.cpp
@@ -1461,8 +1461,14 @@ TextDocumentPtr TextEditorWidget::textDocumentPtr() const
 
 TextEditorWidget *TextEditorWidget::currentTextEditorWidget()
 {
-    auto editor = qobject_cast<BaseTextEditor *>(EditorManager::currentEditor());
-    return editor ? editor->editorWidget() : nullptr;
+    return fromEditor(EditorManager::currentEditor());
+}
+
+TextEditorWidget *TextEditorWidget::fromEditor(const IEditor *editor)
+{
+    if (editor)
+        return Aggregation::query<TextEditorWidget>(editor->widget());
+    return nullptr;
 }
 
 void TextEditorWidgetPrivate::editorContentsChange(int position, int charsRemoved, int charsAdded)
@@ -8370,8 +8376,9 @@ QVector<BaseTextEditor *> BaseTextEditor::textEditorsForDocument(TextDocument *t
 
 TextEditorWidget *BaseTextEditor::editorWidget() const
 {
-    QTC_ASSERT(qobject_cast<TextEditorWidget *>(m_widget.data()), return nullptr);
-    return static_cast<TextEditorWidget *>(m_widget.data());
+    auto textEditorWidget = TextEditorWidget::fromEditor(this);
+    QTC_CHECK(textEditorWidget);
+    return textEditorWidget;
 }
 
 void BaseTextEditor::setTextCursor(const QTextCursor &cursor)
@@ -8649,10 +8656,12 @@ void TextEditorFactory::setParenthesesMatchingEnabled(bool on)
 
 BaseTextEditor *TextEditorFactoryPrivate::createEditorHelper(const TextDocumentPtr &document)
 {
-    TextEditorWidget *widget = m_widgetCreator();
-    widget->setMarksVisible(m_marksVisible);
-    widget->setParenthesesMatchingEnabled(m_paranthesesMatchinEnabled);
-    widget->setCodeFoldingSupported(m_codeFoldingSupported);
+    QWidget *widget = m_widgetCreator();
+    TextEditorWidget *textEditorWidget = Aggregation::query<TextEditorWidget>(widget);
+    QTC_ASSERT(textEditorWidget, return nullptr);
+    textEditorWidget->setMarksVisible(m_marksVisible);
+    textEditorWidget->setParenthesesMatchingEnabled(m_paranthesesMatchinEnabled);
+    textEditorWidget->setCodeFoldingSupported(m_codeFoldingSupported);
 
     BaseTextEditor *editor = m_editorCreator();
     editor->setDuplicateSupported(m_duplicatedSupported);
@@ -8663,25 +8672,25 @@ BaseTextEditor *TextEditorFactoryPrivate::createEditorHelper(const TextDocumentP
 
     // Needs to go before setTextDocument as this copies the current settings.
     if (m_autoCompleterCreator)
-        widget->setAutoCompleter(m_autoCompleterCreator());
+        textEditorWidget->setAutoCompleter(m_autoCompleterCreator());
 
-    widget->setTextDocument(document);
-    widget->autoCompleter()->setTabSettings(document->tabSettings());
-    widget->d->m_hoverHandlers = m_hoverHandlers;
+    textEditorWidget->setTextDocument(document);
+    textEditorWidget->autoCompleter()->setTabSettings(document->tabSettings());
+    textEditorWidget->d->m_hoverHandlers = m_hoverHandlers;
 
-    widget->d->m_codeAssistant.configure(widget);
-    widget->d->m_commentDefinition = m_commentDefinition;
+    textEditorWidget->d->m_codeAssistant.configure(textEditorWidget);
+    textEditorWidget->d->m_commentDefinition = m_commentDefinition;
 
-    QObject::connect(widget,
+    QObject::connect(textEditorWidget,
                      &TextEditorWidget::activateEditor,
-                     widget,
+                     textEditorWidget,
                      [editor](EditorManager::OpenEditorFlags flags) {
                          EditorManager::activateEditor(editor, flags);
                      });
 
     if (m_useGenericHighlighter)
-        widget->setupGenericHighlighter();
-    widget->finalizeInitialization();
+        textEditorWidget->setupGenericHighlighter();
+    textEditorWidget->finalizeInitialization();
     editor->finalizeInitialization();
     return editor;
 }
diff --git a/src/plugins/texteditor/texteditor.h b/src/plugins/texteditor/texteditor.h
index a2512384da..403d2f2b6f 100644
--- a/src/plugins/texteditor/texteditor.h
+++ b/src/plugins/texteditor/texteditor.h
@@ -556,6 +556,7 @@ public:
     void setContextHelpItem(const Core::HelpItem &item);
 
     static TextEditorWidget *currentTextEditorWidget();
+    static TextEditorWidget *fromEditor(const Core::IEditor *editor);
 
 protected:
     /*!
@@ -641,7 +642,8 @@ public:
 
     using EditorCreator = std::function<BaseTextEditor *()>;
     using DocumentCreator = std::function<TextDocument *()>;
-    using EditorWidgetCreator = std::function<TextEditorWidget *()>;
+    // editor widget must be castable (qobject_cast or Aggregate::query) to TextEditorWidget
+    using EditorWidgetCreator = std::function<QWidget *()>;
     using SyntaxHighLighterCreator = std::function<SyntaxHighlighter *()>;
     using IndenterCreator = std::function<Indenter *(QTextDocument *)>;
     using AutoCompleterCreator = std::function<AutoCompleter *()>;
diff --git a/src/plugins/texteditor/texteditoractionhandler.cpp b/src/plugins/texteditor/texteditoractionhandler.cpp
index 4cae664cb4..67d5898509 100644
--- a/src/plugins/texteditor/texteditoractionhandler.cpp
+++ b/src/plugins/texteditor/texteditoractionhandler.cpp
@@ -31,6 +31,8 @@
 #include "texteditorconstants.h"
 #include "texteditorplugin.h"
 
+#include <aggregation/aggregate.h>
+
 #include <coreplugin/locator/locatormanager.h>
 #include <coreplugin/icore.h>
 #include <coreplugin/editormanager/editormanager.h>
@@ -592,7 +594,7 @@ TextEditorActionHandler::TextEditorActionHandler(Core::Id editorId,
     if (resolver)
         d->m_findTextWidget = resolver;
     else
-        d->m_findTextWidget = [](Core::IEditor *editor) { return qobject_cast<TextEditorWidget *>(editor->widget()); };
+        d->m_findTextWidget = TextEditorWidget::fromEditor;
 }
 
 TextEditorActionHandler::~TextEditorActionHandler()