From d0aa81ee104107db1ce41a9bf0f91d4cb144f7de Mon Sep 17 00:00:00 2001
From: Friedemann Kleint <Friedemann.Kleint@digia.com>
Date: Fri, 26 Oct 2012 10:44:00 +0200
Subject: [PATCH] Fix a crash in QFileDialog when selecting an invalid name
 filter.

When nameDetailsVisible is set to false and an invalid/empty
string is passed to selectNameFilter(), the regexp used to
strip the filter off the suffixes returns empty and a crash
occurs.

Change-Id: I926ea49514ff25a103977d8121fca1cf83d647f5
Reviewed-by: Miikka Heikkinen <miikka.heikkinen@digia.com>
Reviewed-by: Sean Harmer <sean.harmer@kdab.com>
---
 src/widgets/dialogs/qfiledialog.cpp           | 12 +++--
 .../dialogs/qfiledialog/tst_qfiledialog.cpp   | 47 ++++++++++++++++++-
 2 files changed, 53 insertions(+), 6 deletions(-)

diff --git a/src/widgets/dialogs/qfiledialog.cpp b/src/widgets/dialogs/qfiledialog.cpp
index d9d318765d..2ff0d03c35 100644
--- a/src/widgets/dialogs/qfiledialog.cpp
+++ b/src/widgets/dialogs/qfiledialog.cpp
@@ -1201,9 +1201,11 @@ void QFileDialog::selectNameFilter(const QString &filter)
         d->selectNameFilter_sys(filter);
         return;
     }
-    int i;
+    int i = -1;
     if (testOption(HideNameFilterDetails)) {
-        i = d->qFileDialogUi->fileTypeCombo->findText(qt_strip_filters(qt_make_filter_list(filter)).first());
+        const QStringList filters = qt_strip_filters(qt_make_filter_list(filter));
+        if (!filters.isEmpty())
+            i = d->qFileDialogUi->fileTypeCombo->findText(filters.first());
     } else {
         i = d->qFileDialogUi->fileTypeCombo->findText(filter);
     }
@@ -1770,7 +1772,7 @@ QString QFileDialog::getOpenFileName(QWidget *parent,
 
     // create a qt dialog
     QFileDialog dialog(args);
-    if (selectedFilter)
+    if (selectedFilter && !selectedFilter->isEmpty())
         dialog.selectNameFilter(*selectedFilter);
     if (dialog.exec() == QDialog::Accepted) {
         if (selectedFilter)
@@ -1855,7 +1857,7 @@ QStringList QFileDialog::getOpenFileNames(QWidget *parent,
 
     // create a qt dialog
     QFileDialog dialog(args);
-    if (selectedFilter)
+    if (selectedFilter && !selectedFilter->isEmpty())
         dialog.selectNameFilter(*selectedFilter);
     if (dialog.exec() == QDialog::Accepted) {
         if (selectedFilter)
@@ -1942,7 +1944,7 @@ QString QFileDialog::getSaveFileName(QWidget *parent,
     // create a qt dialog
     QFileDialog dialog(args);
     dialog.setAcceptMode(AcceptSave);
-    if (selectedFilter)
+    if (selectedFilter && !selectedFilter->isEmpty())
         dialog.selectNameFilter(*selectedFilter);
     if (dialog.exec() == QDialog::Accepted) {
         if (selectedFilter)
diff --git a/tests/auto/widgets/dialogs/qfiledialog/tst_qfiledialog.cpp b/tests/auto/widgets/dialogs/qfiledialog/tst_qfiledialog.cpp
index 32610fda18..8ce0742854 100644
--- a/tests/auto/widgets/dialogs/qfiledialog/tst_qfiledialog.cpp
+++ b/tests/auto/widgets/dialogs/qfiledialog/tst_qfiledialog.cpp
@@ -130,7 +130,9 @@ private slots:
     void selectFilter();
     void viewMode();
     void proxymodel();
+    void setNameFilter_data();
     void setNameFilter();
+    void setEmptyNameFilter();
     void focus();
     void caption();
     void historyBack();
@@ -1003,13 +1005,56 @@ void tst_QFiledialog::proxymodel()
     QCOMPARE(fd.proxyModel(), (QAbstractProxyModel*)0);
 }
 
-void tst_QFiledialog::setNameFilter()
+void tst_QFiledialog::setEmptyNameFilter()
 {
     QNonNativeFileDialog fd;
     fd.setNameFilter(QString());
     fd.setNameFilters(QStringList());
 }
 
+void tst_QFiledialog::setNameFilter_data()
+{
+    QTest::addColumn<bool>("nameFilterDetailsVisible");
+    QTest::addColumn<QStringList>("filters");
+    QTest::addColumn<QString>("selectFilter");
+    QTest::addColumn<QString>("expectedSelectedFilter");
+
+    QTest::newRow("namedetailsvisible-empty") << true << QStringList() << QString() << QString();
+    QTest::newRow("namedetailsinvisible-empty") << false << QStringList() << QString() << QString();
+
+    const QString anyFileNoDetails = QLatin1String("Any files");
+    const QString anyFile = anyFileNoDetails + QLatin1String(" (*)");
+    const QString imageFilesNoDetails = QLatin1String("Image files");
+    const QString imageFiles = imageFilesNoDetails + QLatin1String(" (*.png *.xpm *.jpg)");
+    const QString textFileNoDetails = QLatin1String("Text files");
+    const QString textFile = textFileNoDetails + QLatin1String(" (*.txt)");
+
+    QStringList filters;
+    filters << anyFile << imageFiles << textFile;
+
+    QTest::newRow("namedetailsvisible-images") << true << filters << imageFiles << imageFiles;
+    QTest::newRow("namedetailsinvisible-images") << false << filters << imageFiles << imageFilesNoDetails;
+
+    const QString invalid = "foo";
+    QTest::newRow("namedetailsvisible-invalid") << true << filters << invalid << anyFile;
+    // Potential crash when trying to convert the invalid filter into a list and stripping it, resulting in an empty list.
+    QTest::newRow("namedetailsinvisible-invalid") << false << filters << invalid << anyFileNoDetails;
+}
+
+void tst_QFiledialog::setNameFilter()
+{
+    QFETCH(bool, nameFilterDetailsVisible);
+    QFETCH(QStringList, filters);
+    QFETCH(QString, selectFilter);
+    QFETCH(QString, expectedSelectedFilter);
+
+    QNonNativeFileDialog fd;
+    fd.setNameFilters(filters);
+    fd.setNameFilterDetailsVisible(nameFilterDetailsVisible);
+    fd.selectNameFilter(selectFilter);
+    QCOMPARE(fd.selectedNameFilter(), expectedSelectedFilter);
+}
+
 void tst_QFiledialog::focus()
 {
     QNonNativeFileDialog fd;