Add textutil

src/CMakeLists.txt

@@ -190,6 +190,8 @@ target_sources(akregatorpart PRIVATE
     crashwidget/crashwidget.cpp
 
     utils/filtercolumnsproxymodel.cpp
+    utils/textutil.cpp
+    utils/textutil.h
 
     command/deletesubscriptioncommand.cpp
     command/createfeedcommand.cpp

src/utils/textutil.cpp

+/*
+   SPDX-FileCopyrightText: 2022 Laurent Montel <montel@kde.org>
+
+   SPDX-License-Identifier: GPL-2.0-or-later
+*/
+
+#include "textutil.h"
+
+// code from kitinerary/src/lib/stringutil.cpp
+QChar TextUtil::normalize(QChar c)
+{
+    // case folding
+    const auto n = c.toCaseFolded();
+
+    // if the character has a canonical decomposition use that and skip the
+    // combining diacritic markers following it
+    // see https://en.wikipedia.org/wiki/Unicode_equivalence
+    // see https://en.wikipedia.org/wiki/Combining_character
+    if (n.decompositionTag() == QChar::Canonical) {
+        return n.decomposition().at(0);
+    }
+
+    return n;
+}
+
+QString TextUtil::normalize(QStringView str)
+{
+    QString out;
+    out.reserve(str.size());
+    for (const auto c : str) {
+        out.push_back(normalize(c));
+    }
+    return out;
+}

src/utils/textutil.h

+/*
+   SPDX-FileCopyrightText: 2022 Laurent Montel <montel@kde.org>
+
+   SPDX-License-Identifier: GPL-2.0-or-later
+*/
+
+#pragma once
+#include <QString>
+
+namespace TextUtil
+{
+Q_REQUIRED_RESULT QString normalize(QStringView str);
+Q_REQUIRED_RESULT QChar normalize(QChar c);
+};