TextEditor: schedule update document layout

When generating a lot of text marks we do not need to update the
document for every mark and every property that changes.

Change-Id: Ibba80138f6ebcbbe30a4f741979df69ad62608c1
Reviewed-by: hjk <hjk@qt.io>

src/plugins/texteditor/textdocument.cpp

@@ -970,6 +970,13 @@ void TextDocument::updateLayout() const
     documentLayout->requestUpdate();
 }
 
+void TextDocument::scheduleUpdateLayout() const
+{
+    auto documentLayout = qobject_cast<TextDocumentLayout*>(d->m_document.documentLayout());
+    QTC_ASSERT(documentLayout, return);
+    documentLayout->scheduleUpdate();
+}
+
 TextMarks TextDocument::marks() const
 {
     return d->m_marksCache;
@@ -1001,7 +1008,7 @@ bool TextDocument::addMark(TextMark *mark)
         documentLayout->hasMarks = true;
         documentLayout->maxMarkWidthFactor = newMaxWidthFactor;
         if (fullUpdate)
-            documentLayout->requestUpdate();
+            documentLayout->scheduleUpdate();
         else
             documentLayout->requestExtraAreaUpdate();
         return true;
@@ -1080,7 +1087,7 @@ void TextDocument::removeMark(TextMark *mark)
     removeMarkFromMarksCache(mark);
     emit markRemoved(mark);
     mark->setBaseTextDocument(nullptr);
-    updateLayout();
+    scheduleUpdateLayout();
 }
 
 void TextDocument::updateMark(TextMark *mark)
@@ -1092,7 +1099,7 @@ void TextDocument::updateMark(TextMark *mark)
         userData->removeMark(mark);
         userData->addMark(mark);
     }
-    updateLayout();
+    scheduleUpdateLayout();
 }
 
 void TextDocument::moveMark(TextMark *mark, int previousLine)

src/plugins/texteditor/textdocument.h

@@ -112,6 +112,7 @@ public:
     TextMarks marksAt(int line) const;
     void removeMark(TextMark *mark);
     void updateLayout() const;
+    void scheduleUpdateLayout() const;
     void updateMark(TextMark *mark);
     void moveMark(TextMark *mark, int previousLine);
     void removeMarkFromMarksCache(TextMark *mark);

src/plugins/texteditor/textdocumentlayout.cpp

@@ -638,6 +638,20 @@ void TextDocumentLayout::updateMarksBlock(const QTextBlock &block)
     }
 }
 
+void TextDocumentLayout::scheduleUpdate()
+{
+    if (m_updateScheduled)
+        return;
+    m_updateScheduled = true;
+    QMetaObject::invokeMethod(this, &TextDocumentLayout::requestUpdateNow, Qt::QueuedConnection);
+}
+
+void TextDocumentLayout::requestUpdateNow()
+{
+    m_updateScheduled = false;
+    requestUpdate();
+}
+
 QRectF TextDocumentLayout::blockBoundingRect(const QTextBlock &block) const
 {
     QRectF boundingRect = QPlainTextDocumentLayout::blockBoundingRect(block);

src/plugins/texteditor/textdocumentlayout.h

@@ -237,6 +237,11 @@ public:
     void documentReloaded(TextMarks marks, TextDocument *baseextDocument);
     void updateMarksLineNumber();
     void updateMarksBlock(const QTextBlock &block);
+    void scheduleUpdate();
+    void requestUpdateNow();
+
+private:
+    bool m_updateScheduled = false;
 
 signals:
     void updateExtraArea();

src/plugins/texteditor/textmark.cpp

@@ -242,7 +242,7 @@ void TextMark::removedFromEditor()
 void TextMark::updateMarker()
 {
     if (m_baseTextDocument)
-        m_baseTextDocument->updateLayout();
+        m_baseTextDocument->scheduleUpdateLayout();
 }
 
 void TextMark::setPriority(TextMark::Priority prioriy)