TextEditor: add convenience function to clear all extra highlights

Change-Id: Id3a3c45041a23ba100447d926ed6ab829abbc92b
Reviewed-by: Nikolai Kosjar <nikolai.kosjar@qt.io>

src/plugins/cppeditor/cppeditordocument.cpp

@@ -176,14 +176,8 @@ QByteArray CppEditorDocument::contentsText() const
 
 void CppEditorDocument::applyFontSettings()
 {
-    if (TextEditor::SyntaxHighlighter *highlighter = syntaxHighlighter()) {
-        // Clear all additional formats since they may have changed
-        QTextBlock b = document()->firstBlock();
-        while (b.isValid()) {
-            highlighter->clearExtraFormats(b);
-            b = b.next();
-        }
-    }
+    if (TextEditor::SyntaxHighlighter *highlighter = syntaxHighlighter())
+        highlighter->clearAllExtraFormats(); // Clear all additional formats since they may have changed
     TextDocument::applyFontSettings(); // rehighlights and updates additional formats
     if (m_processor)
         m_processor->semanticRehighlight();

src/plugins/texteditor/syntaxhighlighter.cpp

@@ -721,6 +721,15 @@ void SyntaxHighlighter::clearExtraFormats(const QTextBlock &block)
     d->inReformatBlocks = wasInReformatBlocks;
 }
 
+void SyntaxHighlighter::clearAllExtraFormats()
+{
+    QTextBlock b = document()->firstBlock();
+    while (b.isValid()) {
+        clearExtraFormats(b);
+        b = b.next();
+    }
+}
+
 /* Generate at least n different colors for highlighting, excluding background
  * color. */
 

src/plugins/texteditor/syntaxhighlighter.h

@@ -65,6 +65,7 @@ public:
 
     void setExtraFormats(const QTextBlock &block, QVector<QTextLayout::FormatRange> &&formats);
     void clearExtraFormats(const QTextBlock &block);
+    void clearAllExtraFormats();
 
     static QList<QColor> generateColors(int n, const QColor &background);