Fix case sensitivity handling QSFPM

This patch fixes the breaking of case sensitivity handling. The removal
of QRegExp killed the wrong code paths which leads to inconsistencies
when changing the regular expression throuh methods like
setFilterWildCard or setFilterFixedString. Changing the case sensitivity
also nukes the original options that were set on the regular expression
if it was set through setFilterRegularExpression.

[ChangeLog][QtCore][QSortFilterProxyModel] Case sensitivity as well as
regular expression options handling have been fixed. The original value
is properly kept when using setFilterWildCard and setFilterFixedString.
The regular expression options are now also properly kept when changing
the case senstitivity through setFilterCaseSensitivity.

Fixes: QTBUG-92260
Change-Id: Ifb4732306f0c7d79ad0b18d3f5437c4523bb40e5
Reviewed-by: Igor Kushnir <igorkuo@gmail.com>
Reviewed-by: Giuseppe D'Angelo <giuseppe.dangelo@kdab.com>
(cherry picked from commit bcbbbdb2d640c059c19e9337c7418b83b1b7e4ea)
Reviewed-by: Qt Cherry-pick Bot <cherrypick_bot@qt-project.org>

2 files changed, 110 insertions, 24 deletions

diff --git a/src/corelib/itemmodels/qsortfilterproxymodel.cpp b/src/corelib/itemmodels/qsortfilterproxymodel.cpp
index 7c804d52e8..21b485b398 100644
--- a/src/corelib/itemmodels/qsortfilterproxymodel.cpp
+++ b/src/corelib/itemmodels/qsortfilterproxymodel.cpp
@@ -173,7 +173,7 @@ public:
 
     int filter_column;
     int filter_role;
-    QRegularExpression filter_data;
+    QRegularExpression filter_regularexpression;
     QModelIndex last_top_source;
 
     bool filter_recursive;
@@ -193,6 +193,17 @@ public:
 
     void remove_from_mapping(const QModelIndex &source_parent);
 
+    /*!
+     * Legacy: changing the pattern through a string does not change the
+     * case sensitivity.
+     */
+    void set_filter_pattern(const QString &pattern)
+    {
+        filter_regularexpression.setPattern(pattern);
+        filter_regularexpression.setPatternOptions(filter_regularexpression.patternOptions()
+                                                   & QRegularExpression::CaseInsensitiveOption);
+    }
+
     inline QHash<QModelIndex, Mapping *>::const_iterator index_to_iterator(
         const QModelIndex &proxy_index) const
     {
@@ -1168,9 +1179,10 @@ void QSortFilterProxyModelPrivate::update_persistent_indexes(
 */
 void QSortFilterProxyModelPrivate::filter_about_to_be_changed(const QModelIndex &source_parent)
 {
-  if (!filter_data.pattern().isEmpty() &&
-        source_index_mapping.constFind(source_parent) == source_index_mapping.constEnd())
-    create_mapping(source_parent);
+    if (!filter_regularexpression.pattern().isEmpty()
+        && source_index_mapping.constFind(source_parent) == source_index_mapping.constEnd()) {
+        create_mapping(source_parent);
+    }
 }
 
 
@@ -2493,8 +2505,8 @@ Qt::SortOrder QSortFilterProxyModel::sortOrder() const
     \property QSortFilterProxyModel::filterRegularExpression
     \brief the QRegularExpression used to filter the contents of the source model
 
-    Setting this property overwrites the current
-    \l{QSortFilterProxyModel::filterCaseSensitivity}{filterCaseSensitivity}.
+    Setting this property through the QRegularExpression overload overwrites the
+    current \l{QSortFilterProxyModel::filterCaseSensitivity}{filterCaseSensitivity}.
     By default, the QRegularExpression is an empty string matching all contents.
 
     If no QRegularExpression or an empty string is set, everything in the source
@@ -2505,14 +2517,14 @@ Qt::SortOrder QSortFilterProxyModel::sortOrder() const
 QRegularExpression QSortFilterProxyModel::filterRegularExpression() const
 {
     Q_D(const QSortFilterProxyModel);
-    return d->filter_data;
+    return d->filter_regularexpression;
 }
 
 void QSortFilterProxyModel::setFilterRegularExpression(const QRegularExpression &regularExpression)
 {
     Q_D(QSortFilterProxyModel);
     d->filter_about_to_be_changed();
-    d->filter_data = regularExpression;
+    d->filter_regularexpression = regularExpression;
     d->filter_changed(QSortFilterProxyModelPrivate::Direction::Rows);
 }
 #endif
@@ -2559,20 +2571,21 @@ void QSortFilterProxyModel::setFilterKeyColumn(int column)
 Qt::CaseSensitivity QSortFilterProxyModel::filterCaseSensitivity() const
 {
     Q_D(const QSortFilterProxyModel);
-    return d->filter_data.patternOptions() & QRegularExpression::CaseInsensitiveOption ?
-                Qt::CaseInsensitive : Qt::CaseSensitive;
+    return d->filter_regularexpression.patternOptions() & QRegularExpression::CaseInsensitiveOption
+            ? Qt::CaseInsensitive
+            : Qt::CaseSensitive;
 }
 
 void QSortFilterProxyModel::setFilterCaseSensitivity(Qt::CaseSensitivity cs)
 {
     Q_D(QSortFilterProxyModel);
-    QRegularExpression::PatternOptions o = QRegularExpression::NoPatternOption;
-    if (cs == Qt::CaseInsensitive)
-        o = QRegularExpression::CaseInsensitiveOption;
-    if (o == d->filter_data.patternOptions())
+    QRegularExpression::PatternOptions options = d->filter_regularexpression.patternOptions();
+    options.setFlag(QRegularExpression::CaseInsensitiveOption, cs == Qt::CaseInsensitive);
+    if (d->filter_regularexpression.patternOptions() == options)
         return;
+
     d->filter_about_to_be_changed();
-    d->filter_data.setPatternOptions(o);
+    d->filter_regularexpression.setPatternOptions(options);
     d->filter_changed(QSortFilterProxyModelPrivate::Direction::Rows);
     emit filterCaseSensitivityChanged(cs);
 }
@@ -2653,15 +2666,16 @@ void QSortFilterProxyModel::setSortLocaleAware(bool on)
     This method should be preferred for new code as it will use
     QRegularExpression internally.
 
+    This method will reset the regular expression options
+    but respect case sensitivity.
+
     \sa setFilterCaseSensitivity(), setFilterWildcard(), setFilterFixedString(), filterRegularExpression()
 */
 void QSortFilterProxyModel::setFilterRegularExpression(const QString &pattern)
 {
     Q_D(QSortFilterProxyModel);
     d->filter_about_to_be_changed();
-    QRegularExpression rx(pattern,
-                          d->filter_data.patternOptions() & QRegularExpression::CaseInsensitiveOption);
-    d->filter_data.setPattern(pattern);
+    d->set_filter_pattern(pattern);
     d->filter_changed(QSortFilterProxyModelPrivate::Direction::Rows);
 }
 #endif
@@ -2670,14 +2684,17 @@ void QSortFilterProxyModel::setFilterRegularExpression(const QString &pattern)
     Sets the wildcard expression used to filter the contents
     of the source model to the given \a pattern.
 
+    This method will reset the regular expression options
+    but respect case sensitivity.
+
     \sa setFilterCaseSensitivity(), setFilterRegularExpression(), setFilterFixedString(), filterRegularExpression()
 */
 void QSortFilterProxyModel::setFilterWildcard(const QString &pattern)
 {
     Q_D(QSortFilterProxyModel);
     d->filter_about_to_be_changed();
-    QString p = QRegularExpression::wildcardToRegularExpression(pattern, QRegularExpression::UnanchoredWildcardConversion);
-    d->filter_data.setPattern(p);
+    d->set_filter_pattern(QRegularExpression::wildcardToRegularExpression(
+            pattern, QRegularExpression::UnanchoredWildcardConversion));
     d->filter_changed(QSortFilterProxyModelPrivate::Direction::Rows);
 }
 
@@ -2685,13 +2702,16 @@ void QSortFilterProxyModel::setFilterWildcard(const QString &pattern)
     Sets the fixed string used to filter the contents
     of the source model to the given \a pattern.
 
+    This method will reset the regular expression options
+    but respect case sensitivity.
+
     \sa setFilterCaseSensitivity(), setFilterRegularExpression(), setFilterWildcard(), filterRegularExpression()
 */
 void QSortFilterProxyModel::setFilterFixedString(const QString &pattern)
 {
     Q_D(QSortFilterProxyModel);
     d->filter_about_to_be_changed();
-    d->filter_data.setPattern(QRegularExpression::escape(pattern));
+    d->set_filter_pattern(QRegularExpression::escape(pattern));
     d->filter_changed(QSortFilterProxyModelPrivate::Direction::Rows);
 }
 
@@ -3003,7 +3023,7 @@ bool QSortFilterProxyModel::filterAcceptsRow(int source_row, const QModelIndex &
 {
     Q_D(const QSortFilterProxyModel);
 
-    if (d->filter_data.pattern().isEmpty())
+    if (d->filter_regularexpression.pattern().isEmpty())
         return true;
 
     int column_count = d->model->columnCount(source_parent);
@@ -3011,7 +3031,7 @@ bool QSortFilterProxyModel::filterAcceptsRow(int source_row, const QModelIndex &
         for (int column = 0; column < column_count; ++column) {
             QModelIndex source_index = d->model->index(source_row, column, source_parent);
             QString key = d->model->data(source_index, d->filter_role).toString();
-            if (d->filter_data.match(key).hasMatch())
+            if (key.contains(d->filter_regularexpression))
                 return true;
         }
         return false;
@@ -3021,7 +3041,7 @@ bool QSortFilterProxyModel::filterAcceptsRow(int source_row, const QModelIndex &
         return true;
     QModelIndex source_index = d->model->index(source_row, d->filter_column, source_parent);
     QString key = d->model->data(source_index, d->filter_role).toString();
-    return d->filter_data.match(key).hasMatch();
+    return key.contains(d->filter_regularexpression);
 }
 
 /*!
diff --git a/tests/auto/corelib/itemmodels/qsortfilterproxymodel_regularexpression/tst_qsortfilterproxymodel_regularexpression.cpp b/tests/auto/corelib/itemmodels/qsortfilterproxymodel_regularexpression/tst_qsortfilterproxymodel_regularexpression.cpp
index adeb0cfe5a..9d7ba3ca84 100644
--- a/tests/auto/corelib/itemmodels/qsortfilterproxymodel_regularexpression/tst_qsortfilterproxymodel_regularexpression.cpp
+++ b/tests/auto/corelib/itemmodels/qsortfilterproxymodel_regularexpression/tst_qsortfilterproxymodel_regularexpression.cpp
@@ -39,6 +39,8 @@ public:
 private slots:
     void tst_invalid();
     void tst_caseSensitivity();
+    void tst_keepCaseSensitivity_QTBUG_92260();
+    void tst_keepPatternOptions_QTBUG_92260();
 };
 
 tst_QSortFilterProxyModelRegularExpression::tst_QSortFilterProxyModelRegularExpression() :
@@ -74,5 +76,69 @@ void tst_QSortFilterProxyModelRegularExpression::tst_caseSensitivity()
     QCOMPARE(proxyModel.rowCount(), 2);
 }
 
+/*!
+    This test ensures that when a string pattern is passed to setRegularEpxression,
+    the options are properly reseted but that the case sensitivity is kept as is.
+
+ */
+void tst_QSortFilterProxyModelRegularExpression::tst_keepCaseSensitivity_QTBUG_92260()
+{
+    const QLatin1String pattern("test");
+    QStringListModel model({ "test", "TesT" });
+    QSortFilterProxyModel proxyModel;
+    proxyModel.setSourceModel(&model);
+
+    QRegularExpression patternWithOptions("Dummy",
+                                          QRegularExpression::MultilineOption
+                                                  | QRegularExpression::CaseInsensitiveOption);
+
+    proxyModel.setFilterRegularExpression(patternWithOptions);
+    QCOMPARE(proxyModel.filterRegularExpression(), patternWithOptions);
+    QCOMPARE(proxyModel.filterCaseSensitivity(), Qt::CaseInsensitive);
+
+    proxyModel.setFilterRegularExpression(pattern);
+    QCOMPARE(proxyModel.filterCaseSensitivity(), Qt::CaseInsensitive);
+    QCOMPARE(proxyModel.filterRegularExpression().patternOptions(),
+             QRegularExpression::CaseInsensitiveOption);
+
+    patternWithOptions.setPatternOptions(QRegularExpression::MultilineOption);
+    proxyModel.setFilterRegularExpression(patternWithOptions);
+    QCOMPARE(proxyModel.filterCaseSensitivity(), Qt::CaseSensitive);
+    QCOMPARE(proxyModel.filterRegularExpression(), patternWithOptions);
+
+    proxyModel.setFilterRegularExpression(pattern);
+    QCOMPARE(proxyModel.filterCaseSensitivity(), Qt::CaseSensitive);
+    QCOMPARE(proxyModel.filterRegularExpression().patternOptions(),
+             QRegularExpression::NoPatternOption);
+}
+
+/*!
+    This test ensures that when the case sensitivity is changed, it does not nuke
+    the pattern options that were set before.
+ */
+void tst_QSortFilterProxyModelRegularExpression::tst_keepPatternOptions_QTBUG_92260()
+{
+    QStringListModel model({ "test", "TesT" });
+    QSortFilterProxyModel proxyModel;
+    proxyModel.setSourceModel(&model);
+
+    QRegularExpression patternWithOptions("Dummy",
+                                          QRegularExpression::MultilineOption
+                                                  | QRegularExpression::CaseInsensitiveOption);
+
+    proxyModel.setFilterRegularExpression(patternWithOptions);
+    QCOMPARE(proxyModel.filterRegularExpression(), patternWithOptions);
+
+    proxyModel.setFilterCaseSensitivity(Qt::CaseInsensitive);
+    QCOMPARE(proxyModel.filterCaseSensitivity(), Qt::CaseInsensitive);
+    QCOMPARE(proxyModel.filterRegularExpression().patternOptions(),
+             patternWithOptions.patternOptions());
+
+    proxyModel.setFilterCaseSensitivity(Qt::CaseSensitive);
+    QCOMPARE(proxyModel.filterCaseSensitivity(), Qt::CaseSensitive);
+    QCOMPARE(proxyModel.filterRegularExpression().patternOptions(),
+             QRegularExpression::MultilineOption);
+}
+
 QTEST_MAIN(tst_QSortFilterProxyModelRegularExpression)
 #include "tst_qsortfilterproxymodel_regularexpression.moc"