From 6a873778b976b4752e874a2d87ea84e5d9e0d3c5 Mon Sep 17 00:00:00 2001
From: Ivan Solovev <ivan.solovev@qt.io>
Date: Fri, 25 Aug 2023 15:35:08 +0200
Subject: [PATCH] QAbstractProxyModel: fix binding loops

... by using valueBypassingBindings() when accessing the properties
from the setters.

This commit is mostly trivial.
Had to change the template parameters in the unit-test, because the
updated QTestPrivate::testReadWritePropertyBasics() creates an instance
of the TestedClass, and QAbstractProxyModel cannot be instantiated,
since it has pure virtual methods.

Task-number: QTBUG-116346
Pick-to: 6.6 6.5
Change-Id: I0cae29263ea9bb92c9de06891b0ba8633fb9fd72
Reviewed-by: Ulf Hermann <ulf.hermann@qt.io>
---
 src/corelib/itemmodels/qabstractproxymodel.cpp        | 11 ++++++-----
 .../qabstractproxymodel/tst_qabstractproxymodel.cpp   |  6 +++---
 2 files changed, 9 insertions(+), 8 deletions(-)

diff --git a/src/corelib/itemmodels/qabstractproxymodel.cpp b/src/corelib/itemmodels/qabstractproxymodel.cpp
index 12974b5aaa..83e8cb8db3 100644
--- a/src/corelib/itemmodels/qabstractproxymodel.cpp
+++ b/src/corelib/itemmodels/qabstractproxymodel.cpp
@@ -166,7 +166,8 @@ void QAbstractProxyModel::setSourceModel(QAbstractItemModel *sourceModel)
     d->model.removeBindingUnlessInWrapper();
     // Special case to handle nullptr models. Otherwise we will have unwanted
     // notifications.
-    if (!sourceModel && d->model == QAbstractItemModelPrivate::staticEmptyModel())
+    const QAbstractItemModel *currentModel = d->model.valueBypassingBindings();
+    if (!sourceModel && currentModel == QAbstractItemModelPrivate::staticEmptyModel())
         return;
     static const struct {
         const char *signalName;
@@ -183,16 +184,16 @@ void QAbstractProxyModel::setSourceModel(QAbstractItemModel *sourceModel)
         // clang-format on
     };
 
-    if (sourceModel != d->model) {
-        if (d->model) {
+    if (sourceModel != currentModel) {
+        if (currentModel) {
             for (const auto &c : connectionTable)
-                disconnect(d->model, c.signalName, this, c.slotName);
+                disconnect(currentModel, c.signalName, this, c.slotName);
         }
 
         if (sourceModel) {
             d->model.setValueBypassingBindings(sourceModel);
             for (const auto &c : connectionTable)
-                connect(d->model, c.signalName, this, c.slotName);
+                connect(sourceModel, c.signalName, this, c.slotName);
         } else {
             d->model.setValueBypassingBindings(QAbstractItemModelPrivate::staticEmptyModel());
         }
diff --git a/tests/auto/corelib/itemmodels/qabstractproxymodel/tst_qabstractproxymodel.cpp b/tests/auto/corelib/itemmodels/qabstractproxymodel/tst_qabstractproxymodel.cpp
index d04d148fc3..4a9606d345 100644
--- a/tests/auto/corelib/itemmodels/qabstractproxymodel/tst_qabstractproxymodel.cpp
+++ b/tests/auto/corelib/itemmodels/qabstractproxymodel/tst_qabstractproxymodel.cpp
@@ -610,7 +610,7 @@ void tst_QAbstractProxyModel::sourceModelBinding()
     SubQAbstractProxyModel proxy;
     QStandardItemModel model1;
     QStandardItemModel model2;
-    QTestPrivate::testReadWritePropertyBasics<QAbstractProxyModel, QAbstractItemModel *>(
+    QTestPrivate::testReadWritePropertyBasics<SubQAbstractProxyModel, QAbstractItemModel *>(
             proxy, &model1, &model2, "sourceModel");
     if (QTest::currentTestFailed()) {
         qDebug("Failed model - model test");
@@ -618,7 +618,7 @@ void tst_QAbstractProxyModel::sourceModelBinding()
     }
 
     proxy.setSourceModel(&model2);
-    QTestPrivate::testReadWritePropertyBasics<QAbstractProxyModel, QAbstractItemModel *>(
+    QTestPrivate::testReadWritePropertyBasics<SubQAbstractProxyModel, QAbstractItemModel *>(
             proxy, &model1, nullptr, "sourceModel");
     if (QTest::currentTestFailed()) {
         qDebug("Failed model - nullptr test");
@@ -626,7 +626,7 @@ void tst_QAbstractProxyModel::sourceModelBinding()
     }
 
     proxy.setSourceModel(&model1);
-    QTestPrivate::testReadWritePropertyBasics<QAbstractProxyModel, QAbstractItemModel *>(
+    QTestPrivate::testReadWritePropertyBasics<SubQAbstractProxyModel, QAbstractItemModel *>(
             proxy, nullptr, &model2, "sourceModel");
     if (QTest::currentTestFailed()) {
         qDebug("Failed nullptr - model test");