2 files changed, 48 insertions, 0 deletions

diff --git a/src/corelib/itemmodels/qsortfilterproxymodel.cpp b/src/corelib/itemmodels/qsortfilterproxymodel.cpp
index 15798d5293..5ae4fc0417 100644
--- a/src/corelib/itemmodels/qsortfilterproxymodel.cpp
+++ b/src/corelib/itemmodels/qsortfilterproxymodel.cpp
@@ -272,6 +272,7 @@ public:
     QModelIndexPairList store_persistent_indexes();
     void update_persistent_indexes(const QModelIndexPairList &source_indexes);
 
+    void filter_about_to_be_changed(const QModelIndex &source_parent = QModelIndex());
     void filter_changed(const QModelIndex &source_parent = QModelIndex());
     QSet<int> handle_filter_changed(
         QVector<int> &source_to_proxy, QVector<int> &proxy_to_source,
@@ -1045,6 +1046,19 @@ void QSortFilterProxyModelPrivate::update_persistent_indexes(
     q->changePersistentIndexList(from, to);
 }
 
+/*!
+  \internal
+
+  Updates the source_index mapping in case it's invalid and we
+  need it because we have a valid filter
+*/
+void QSortFilterProxyModelPrivate::filter_about_to_be_changed(const QModelIndex &source_parent)
+{
+  if (!filter_regexp.pattern().isEmpty() &&
+        source_index_mapping.constFind(source_parent) == source_index_mapping.constEnd())
+    create_mapping(source_parent);
+}
+
 
 /*!
   \internal
@@ -2304,6 +2318,7 @@ QRegExp QSortFilterProxyModel::filterRegExp() const
 void QSortFilterProxyModel::setFilterRegExp(const QRegExp &regExp)
 {
     Q_D(QSortFilterProxyModel);
+    d->filter_about_to_be_changed();
     d->filter_regexp = regExp;
     d->filter_changed();
 }
@@ -2325,6 +2340,7 @@ int QSortFilterProxyModel::filterKeyColumn() const
 void QSortFilterProxyModel::setFilterKeyColumn(int column)
 {
     Q_D(QSortFilterProxyModel);
+    d->filter_about_to_be_changed();
     d->filter_column = column;
     d->filter_changed();
 }
@@ -2350,6 +2366,7 @@ void QSortFilterProxyModel::setFilterCaseSensitivity(Qt::CaseSensitivity cs)
     Q_D(QSortFilterProxyModel);
     if (cs == d->filter_regexp.caseSensitivity())
         return;
+    d->filter_about_to_be_changed();
     d->filter_regexp.setCaseSensitivity(cs);
     d->filter_changed();
 }
@@ -2415,6 +2432,7 @@ void QSortFilterProxyModel::setSortLocaleAware(bool on)
 void QSortFilterProxyModel::setFilterRegExp(const QString &pattern)
 {
     Q_D(QSortFilterProxyModel);
+    d->filter_about_to_be_changed();
     d->filter_regexp.setPatternSyntax(QRegExp::RegExp);
     d->filter_regexp.setPattern(pattern);
     d->filter_changed();
@@ -2429,6 +2447,7 @@ void QSortFilterProxyModel::setFilterRegExp(const QString &pattern)
 void QSortFilterProxyModel::setFilterWildcard(const QString &pattern)
 {
     Q_D(QSortFilterProxyModel);
+    d->filter_about_to_be_changed();
     d->filter_regexp.setPatternSyntax(QRegExp::Wildcard);
     d->filter_regexp.setPattern(pattern);
     d->filter_changed();
@@ -2443,6 +2462,7 @@ void QSortFilterProxyModel::setFilterWildcard(const QString &pattern)
 void QSortFilterProxyModel::setFilterFixedString(const QString &pattern)
 {
     Q_D(QSortFilterProxyModel);
+    d->filter_about_to_be_changed();
     d->filter_regexp.setPatternSyntax(QRegExp::FixedString);
     d->filter_regexp.setPattern(pattern);
     d->filter_changed();
@@ -2522,6 +2542,7 @@ void QSortFilterProxyModel::setFilterRole(int role)
     Q_D(QSortFilterProxyModel);
     if (d->filter_role == role)
         return;
+    d->filter_about_to_be_changed();
     d->filter_role = role;
     d->filter_changed();
 }
diff --git a/tests/auto/corelib/itemmodels/qsortfilterproxymodel/tst_qsortfilterproxymodel.cpp b/tests/auto/corelib/itemmodels/qsortfilterproxymodel/tst_qsortfilterproxymodel.cpp
index 01c10886c5..bd9e858091 100644
--- a/tests/auto/corelib/itemmodels/qsortfilterproxymodel/tst_qsortfilterproxymodel.cpp
+++ b/tests/auto/corelib/itemmodels/qsortfilterproxymodel/tst_qsortfilterproxymodel.cpp
@@ -87,6 +87,7 @@ private slots:
     void filter_qtbug30662();
 
     void changeSourceLayout();
+    void changeSourceLayoutFilteredOut();
     void removeSourceRows_data();
     void removeSourceRows();
     void insertSourceRows_data();
@@ -1533,6 +1534,32 @@ void tst_QSortFilterProxyModel::changeSourceLayout()
     }
 }
 
+void tst_QSortFilterProxyModel::changeSourceLayoutFilteredOut()
+{
+    QStandardItemModel model(2, 1);
+    model.setData(model.index(0, 0), QString("b"));
+    model.setData(model.index(1, 0), QString("a"));
+    QSortFilterProxyModel proxy;
+    proxy.setSourceModel(&model);
+
+    int beforeSortFilter = proxy.rowCount();
+
+    QSignalSpy removeSpy(&proxy, &QSortFilterProxyModel::rowsRemoved);
+    // Filter everything out
+    proxy.setFilterRegExp(QRegExp("c"));
+    QCOMPARE(removeSpy.count(), 1);
+    QCOMPARE(0, proxy.rowCount());
+
+    // change layout of source model
+    model.sort(0, Qt::AscendingOrder);
+
+    QSignalSpy insertSpy(&proxy, &QSortFilterProxyModel::rowsInserted);
+    // Remove filter; we expect an insert
+    proxy.setFilterRegExp(QRegExp(""));
+    QCOMPARE(insertSpy.count(), 1);
+    QCOMPARE(beforeSortFilter, proxy.rowCount());
+}
+
 void tst_QSortFilterProxyModel::removeSourceRows_data()
 {
     QTest::addColumn<QStringList>("sourceItems");