KStandardItemListWidget: select by number of unicode chars

Previously during rename, the number of QChar is used for selection,
which might be different from number of unicode characters.

Test plan:
- create the file zz❤️❤️.txt
- rename the file
- verify that the first 4 characters are correctly selected, which
  didn't work before the patch.

BUG: 466814

1 files changed, 3 insertions, 1 deletions

diff --git a/src/kitemviews/kstandarditemlistwidget.h b/src/kitemviews/kstandarditemlistwidget.h
index 35392b420..02f897dbe 100644
--- a/src/kitemviews/kstandarditemlistwidget.h
+++ b/src/kitemviews/kstandarditemlistwidget.h
@@ -159,6 +159,8 @@ protected:
      */
     QString roleText(const QByteArray &role, const QHash<QByteArray, QVariant> &values) const;
 
+    static int numberOfUnicodeCharactersIn(const QString &text);
+
     /**
      * Fixes:
      * Select the text without MIME-type extension
@@ -168,7 +170,7 @@ protected:
      * Inherited classes can define, if the MIME-type extension
      * should be selected or not.
      *
-     * @return Selection length (with or without MIME-type extension)
+     * @return Selection length (with or without MIME-type extension) in number of unicode characters, which might be different from number of QChars.
      */
     virtual int selectionLength(const QString &text) const;