Improve detection of file extension string

src/base/utils/fs.cpp

@@ -55,6 +55,7 @@
 #include <QDirIterator>
 #include <QFile>
 #include <QFileInfo>
+#include <QMimeDatabase>
 #include <QStorageInfo>
 #include <QRegularExpression>
 
@@ -76,9 +77,14 @@ QString Utils::Fs::toUniformPath(const QString &path)
  */
 QString Utils::Fs::fileExtension(const QString &filename)
 {
-    const QString ext = QString(filename).remove(QB_EXT);
-    const int pointIndex = ext.lastIndexOf('.');
-    return (pointIndex >= 0) ? ext.mid(pointIndex + 1) : QString();
+    const QString name = filename.endsWith(QB_EXT)
+#if (QT_VERSION >= QT_VERSION_CHECK(5, 10, 0))
+        ? filename.chopped(QB_EXT.length())
+#else
+        ? filename.left(filename.length() - QB_EXT.length())
+#endif
+        : filename;
+    return QMimeDatabase().suffixForFileName(name);
 }
 
 QString Utils::Fs::fileName(const QString &filePath)

src/gui/autoexpandabledialog.cpp

@@ -28,6 +28,7 @@
 
 #include "autoexpandabledialog.h"
 
+#include "base/utils/fs.h"
 #include "ui_autoexpandabledialog.h"
 #include "utils.h"
 
@@ -57,12 +58,9 @@ QString AutoExpandableDialog::getText(QWidget *parent, const QString &title, con
     d.m_ui->textEdit->selectAll();
     if (excludeExtension)
     {
-        int lastDotIndex = text.lastIndexOf('.');
-        if ((lastDotIndex > 3) && (text.mid(lastDotIndex - 4, 4).toLower() == ".tar"))
-            lastDotIndex -= 4;
-        // Select file name without extension, except dot files like .gitignore
-        if (lastDotIndex > 0)
-            d.m_ui->textEdit->setSelection(0, lastDotIndex);
+        const QString extension = Utils::Fs::fileExtension(text);
+        if (!extension.isEmpty())
+            d.m_ui->textEdit->setSelection(0, (text.length() - extension.length() - 1));
     }
 
     bool res = d.exec();