qt6-declarative/0001-Revert-QQmlDelegateModel-fix-delegates-not-being-cre.patch

From 3330731d0cb221477ab3d856db032126403ae6a0 Mon Sep 17 00:00:00 2001
From: Mitch Curtis <mitch.curtis@qt.io>
Date: Tue, 24 Sep 2024 08:18:14 +0800
Subject: [PATCH 1/2] Revert "QQmlDelegateModel: fix delegates not being
 created in certain cases"

This reverts commit 6561344dd2d1ba69abe6edec4fe340b256da9e13. It needs
to be fixed in a different way.

Fixes: QTBUG-127340
Pick-to: 6.7 6.5
Change-Id: I8503b22a5257e0fb5ee11a1bdf83d3dcab4a600a
Reviewed-by: Richard Moe Gustavsen <richard.gustavsen@qt.io>
(cherry picked from commit 281f620ceea03e7a222d796ae0cca917a9778368)
Reviewed-by: Qt Cherry-pick Bot <cherrypick_bot@qt-project.org>
---
 src/qmlmodels/qqmldelegatemodel.cpp           |  61 +++-----
 src/qmlmodels/qqmldelegatemodel_p_p.h         |   2 -
 .../auto/qml/qqmldelegatemodel/CMakeLists.txt |   1 -
 .../auto/qml/qqmldelegatemodel/data/reset.qml |  28 ----
 .../data/resetInQAIMConstructor.qml           |  28 ----
 .../tst_qqmldelegatemodel.cpp                 | 135 ++----------------
 6 files changed, 29 insertions(+), 226 deletions(-)
 delete mode 100644 tests/auto/qml/qqmldelegatemodel/data/reset.qml
 delete mode 100644 tests/auto/qml/qqmldelegatemodel/data/resetInQAIMConstructor.qml

diff --git a/src/qmlmodels/qqmldelegatemodel.cpp b/src/qmlmodels/qqmldelegatemodel.cpp
index 9af58d7a22..7cfa662aa6 100644
--- a/src/qmlmodels/qqmldelegatemodel.cpp
+++ b/src/qmlmodels/qqmldelegatemodel.cpp
@@ -172,7 +172,6 @@ QQmlDelegateModelPrivate::QQmlDelegateModelPrivate(QQmlContext *ctxt)
     , m_transaction(false)
     , m_incubatorCleanupScheduled(false)
     , m_waitingToFetchMore(false)
-    , m_maybeResetRoleNames(false)
     , m_cacheItems(nullptr)
     , m_items(nullptr)
     , m_persistedItems(nullptr)
@@ -366,7 +365,6 @@ void QQmlDelegateModelPrivate::connectToAbstractItemModel()
     QObject::connect(aim, &QAbstractItemModel::dataChanged, q, &QQmlDelegateModel::_q_dataChanged);
     QObject::connect(aim, &QAbstractItemModel::rowsMoved, q, &QQmlDelegateModel::_q_rowsMoved);
     QObject::connect(aim, &QAbstractItemModel::modelAboutToBeReset, q, &QQmlDelegateModel::_q_modelAboutToBeReset);
-    QObject::connect(aim, &QAbstractItemModel::modelReset, q, &QQmlDelegateModel::handleModelReset);
     QObject::connect(aim, &QAbstractItemModel::layoutChanged, q, &QQmlDelegateModel::_q_layoutChanged);
 }
 
@@ -387,7 +385,6 @@ void QQmlDelegateModelPrivate::disconnectFromAbstractItemModel()
     QObject::disconnect(aim, &QAbstractItemModel::dataChanged, q, &QQmlDelegateModel::_q_dataChanged);
     QObject::disconnect(aim, &QAbstractItemModel::rowsMoved, q, &QQmlDelegateModel::_q_rowsMoved);
     QObject::disconnect(aim, &QAbstractItemModel::modelAboutToBeReset, q, &QQmlDelegateModel::_q_modelAboutToBeReset);
-    QObject::disconnect(aim, &QAbstractItemModel::modelReset, q, &QQmlDelegateModel::handleModelReset);
     QObject::disconnect(aim, &QAbstractItemModel::layoutChanged, q, &QQmlDelegateModel::_q_layoutChanged);
 }
 
@@ -1898,28 +1895,25 @@ void QQmlDelegateModel::_q_modelAboutToBeReset()
     Q_D(QQmlDelegateModel);
     if (!d->m_adaptorModel.adaptsAim())
         return;
-
-    /*
-        roleNames are generally guaranteed to be stable (given that QAIM has no
-        change signal for them), except that resetting the model is allowed to
-        invalidate them (QTBUG-32132). DelegateModel must take this into account by
-        snapshotting the current roleNames before the model is reset.
-        Afterwards, if we detect that roleNames has changed, we throw the
-        current model set up away and rebuild everything from scratch – it is
-        unlikely that a more efficient implementation would be worth it.
-
-        If we detect no changes, we simply use the existing logic to handle the
-        model reset.
-
-        This (role name resetting) logic relies on the fact that
-        modelAboutToBeReset must be followed by a modelReset signal before any
-        further modelAboutToBeReset can occur. However, it's possible for user
-        code to begin the reset before connectToAbstractItemModel is called
-        (QTBUG-125053), in which case we don't attempt to reset the role names.
-    */
-    Q_ASSERT(!d->m_maybeResetRoleNames);
-    d->m_maybeResetRoleNames = true;
-    d->m_roleNamesBeforeReset = d->m_adaptorModel.aim()->roleNames();
+    auto aim = d->m_adaptorModel.aim();
+    auto oldRoleNames = aim->roleNames();
+    // this relies on the fact that modelAboutToBeReset must be followed
+    // by a modelReset signal before any further modelAboutToBeReset can occur
+    QObject::connect(aim, &QAbstractItemModel::modelReset, this, [this, d, oldRoleNames, aim](){
+        if (!d->m_adaptorModel.adaptsAim() || d->m_adaptorModel.aim() != aim)
+            return;
+        if (oldRoleNames == aim->roleNames()) {
+            // if the rolenames stayed the same (most common case), then we don't have
+            // to throw away all the setup that we did
+            handleModelReset();
+        } else {
+            // If they did change, we give up and just start from scratch via setMode
+            setModel(QVariant::fromValue(model()));
+            // but we still have to call handleModelReset, otherwise views will
+            // not refresh
+            handleModelReset();
+        }
+    }, Qt::SingleShotConnection);
 }
 
 void QQmlDelegateModel::handleModelReset()
@@ -1929,23 +1923,6 @@ void QQmlDelegateModel::handleModelReset()
         return;
 
     int oldCount = d->m_count;
-
-    if (d->m_maybeResetRoleNames) {
-        auto aim = d->m_adaptorModel.aim();
-        if (!d->m_adaptorModel.adaptsAim() || d->m_adaptorModel.aim() != aim)
-            return;
-
-        // If the role names stayed the same (most common case), then we don't have
-        // to throw away all the setup that we did.
-        // If they did change, we give up and just start from scratch via setModel.
-        // We do this before handling the reset to ensure that views refresh.
-        if (aim->roleNames() != d->m_roleNamesBeforeReset)
-            setModel(QVariant::fromValue(model()));
-
-        d->m_maybeResetRoleNames = false;
-        d->m_roleNamesBeforeReset.clear();
-    }
-
     d->m_adaptorModel.rootIndex = QModelIndex();
 
     if (d->m_complete) {
diff --git a/src/qmlmodels/qqmldelegatemodel_p_p.h b/src/qmlmodels/qqmldelegatemodel_p_p.h
index bae8fc8a23..3c7ab9281d 100644
--- a/src/qmlmodels/qqmldelegatemodel_p_p.h
+++ b/src/qmlmodels/qqmldelegatemodel_p_p.h
@@ -334,7 +334,6 @@ public:
     QQmlReusableDelegateModelItemsPool m_reusableItemsPool;
     QList<QQDMIncubationTask *> m_finishedIncubating;
     QList<QByteArray> m_watchedRoles;
-    QHash<int, QByteArray> m_roleNamesBeforeReset;
 
     QString m_filterGroup;
 
@@ -348,7 +347,6 @@ public:
     bool m_transaction : 1;
     bool m_incubatorCleanupScheduled : 1;
     bool m_waitingToFetchMore : 1;
-    bool m_maybeResetRoleNames : 1;
 
     union {
         struct {
diff --git a/tests/auto/qml/qqmldelegatemodel/CMakeLists.txt b/tests/auto/qml/qqmldelegatemodel/CMakeLists.txt
index 966f5229df..8d8a90e0a7 100644
--- a/tests/auto/qml/qqmldelegatemodel/CMakeLists.txt
+++ b/tests/auto/qml/qqmldelegatemodel/CMakeLists.txt
@@ -29,7 +29,6 @@ qt_internal_add_test(tst_qqmldelegatemodel
         Qt::QmlModelsPrivate
         Qt::QmlPrivate
         Qt::Quick
-        Qt::QuickPrivate
         Qt::QuickTestUtilsPrivate
     TESTDATA ${test_data}
 )
diff --git a/tests/auto/qml/qqmldelegatemodel/data/reset.qml b/tests/auto/qml/qqmldelegatemodel/data/reset.qml
deleted file mode 100644
index 0fcd5e8afa..0000000000
--- a/tests/auto/qml/qqmldelegatemodel/data/reset.qml
+++ /dev/null
@@ -1,28 +0,0 @@
-import QtQuick
-import Test
-
-Window {
-    id: root
-    width: 200
-    height: 200
-
-    property alias listView: listView
-
-    ResettableModel {
-        id: resetModel
-    }
-
-    ListView {
-        id: listView
-        anchors.fill: parent
-        model: resetModel
-
-        delegate: Rectangle {
-            implicitWidth: 100
-            implicitHeight: 50
-            color: "olivedrab"
-
-            required property string display
-        }
-    }
-}
diff --git a/tests/auto/qml/qqmldelegatemodel/data/resetInQAIMConstructor.qml b/tests/auto/qml/qqmldelegatemodel/data/resetInQAIMConstructor.qml
deleted file mode 100644
index cb1f226737..0000000000
--- a/tests/auto/qml/qqmldelegatemodel/data/resetInQAIMConstructor.qml
+++ /dev/null
@@ -1,28 +0,0 @@
-import QtQuick
-import Test
-
-Window {
-    id: root
-    width: 200
-    height: 200
-
-    property alias listView: listView
-
-    ResetInConstructorModel {
-        id: resetInConstructorModel
-    }
-
-    ListView {
-        id: listView
-        anchors.fill: parent
-        model: resetInConstructorModel
-
-        delegate: Rectangle {
-            implicitWidth: 100
-            implicitHeight: 50
-            color: "olivedrab"
-
-            required property string display
-        }
-    }
-}
diff --git a/tests/auto/qml/qqmldelegatemodel/tst_qqmldelegatemodel.cpp b/tests/auto/qml/qqmldelegatemodel/tst_qqmldelegatemodel.cpp
index d9f8b7aeba..2cacda5513 100644
--- a/tests/auto/qml/qqmldelegatemodel/tst_qqmldelegatemodel.cpp
+++ b/tests/auto/qml/qqmldelegatemodel/tst_qqmldelegatemodel.cpp
@@ -4,7 +4,6 @@
 #include <QtTest/qtest.h>
 #include <QtCore/qjsonobject.h>
 #include <QtCore/QConcatenateTablesProxyModel>
-#include <QtCore/qtimer.h>
 #include <QtGui/QStandardItemModel>
 #include <QtQml/qqmlcomponent.h>
 #include <QtQml/qqmlapplicationengine.h>
@@ -12,17 +11,11 @@
 #include <QtQmlModels/private/qqmllistmodel_p.h>
 #include <QtQuick/qquickview.h>
 #include <QtQuick/qquickitem.h>
-#include <QtQuick/private/qquickitemview_p_p.h>
-#include <QtQuick/private/qquicklistview_p.h>
-#include <QtQuickTest/quicktest.h>
 #include <QtQuickTestUtils/private/qmlutils_p.h>
-#include <QtQuickTestUtils/private/visualtestutils_p.h>
 #include <QtTest/QSignalSpy>
 
 #include <forward_list>
 
-using namespace QQuickVisualTestUtils;
-
 class tst_QQmlDelegateModel : public QQmlDataTest
 {
     Q_OBJECT
@@ -32,8 +25,6 @@ public:
 
 private slots:
     void resettingRolesRespected();
-    void resetInQAIMConstructor();
-    void reset();
     void valueWithoutCallingObjectFirst_data();
     void valueWithoutCallingObjectFirst();
     void qtbug_86017();
@@ -53,9 +44,16 @@ private slots:
     void viewUpdatedOnDelegateChoiceAffectingRoleChange();
 };
 
-class BaseAbstractItemModel : public QAbstractItemModel
+class AbstractItemModel : public QAbstractItemModel
 {
+    Q_OBJECT
 public:
+    AbstractItemModel()
+    {
+        for (int i = 0; i < 3; ++i)
+            mValues.append(QString::fromLatin1("Item %1").arg(i));
+    }
+
     QModelIndex index(int row, int column, const QModelIndex &parent = QModelIndex()) const override
     {
         if (parent.isValid())
@@ -93,21 +91,10 @@ public:
         return mValues.at(index.row());
     }
 
-protected:
+private:
     QVector<QString> mValues;
 };
 
-class AbstractItemModel : public BaseAbstractItemModel
-{
-    Q_OBJECT
-public:
-    AbstractItemModel()
-    {
-        for (int i = 0; i < 3; ++i)
-            mValues.append(QString::fromLatin1("Item %1").arg(i));
-    }
-};
-
 tst_QQmlDelegateModel::tst_QQmlDelegateModel()
     : QQmlDataTest(QT_QMLTEST_DATADIR)
 {
@@ -166,109 +153,7 @@ void tst_QQmlDelegateModel::resettingRolesRespected()
     QObject *root = engine.rootObjects().constFirst();
     QVERIFY(!root->property("success").toBool());
     model->change();
-    QTRY_VERIFY_WITH_TIMEOUT(root->property("success").toBool(), 100);
-}
-
-class ResetInConstructorModel : public BaseAbstractItemModel
-{
-    Q_OBJECT
-    QML_ELEMENT
-
-public:
-    ResetInConstructorModel()
-    {
-        beginResetModel();
-        QTimer::singleShot(0, this, &ResetInConstructorModel::finishReset);
-    }
-
-private:
-    void finishReset()
-    {
-        mValues.append("First");
-        endResetModel();
-    }
-};
-
-void tst_QQmlDelegateModel::resetInQAIMConstructor()
-{
-    qmlRegisterTypesAndRevisions<ResetInConstructorModel>("Test", 1);
-
-    QQuickApplicationHelper helper(this, "resetInQAIMConstructor.qml");
-    QVERIFY2(helper.ready, helper.failureMessage());
-    QQuickWindow *window = helper.window;
-    window->show();
-    QVERIFY(QTest::qWaitForWindowExposed(window));
-
-    auto *listView = window->property("listView").value<QQuickListView *>();
-    QVERIFY(listView);
-    QTRY_VERIFY_WITH_TIMEOUT(listView->itemAtIndex(0), 100);
-    QQuickItem *firstDelegateItem = listView->itemAtIndex(0);
-    QVERIFY(firstDelegateItem);
-    QCOMPARE(firstDelegateItem->property("display").toString(), "First");
-}
-
-class ResettableModel : public BaseAbstractItemModel
-{
-    Q_OBJECT
-    QML_ELEMENT
-
-public:
-    ResettableModel()
-    {
-        mValues.append("First");
-    }
-
-    void callBeginResetModel()
-    {
-        beginResetModel();
-        mValues.clear();
-    }
-
-    void appendData()
-    {
-        mValues.append(QString::fromLatin1("Item %1").arg(mValues.size()));
-    }
-
-    void callEndResetModel()
-    {
-        endResetModel();
-    }
-};
-
-// Tests that everything works as expected when calling beginResetModel/endResetModel
-// after the QAIM subclass constructor has run.
-void tst_QQmlDelegateModel::reset()
-{
-    qmlRegisterTypesAndRevisions<ResettableModel>("Test", 1);
-
-    QQuickApplicationHelper helper(this, "reset.qml");
-    QVERIFY2(helper.ready, helper.failureMessage());
-    QQuickWindow *window = helper.window;
-    window->show();
-    QVERIFY(QTest::qWaitForWindowExposed(window));
-
-    auto *listView = window->property("listView").value<QQuickListView *>();
-    QVERIFY(listView);
-    QQuickItem *firstDelegateItem = listView->itemAtIndex(0);
-    QVERIFY(firstDelegateItem);
-    QCOMPARE(firstDelegateItem->property("display").toString(), "First");
-
-    const auto delegateModel = QQuickItemViewPrivate::get(listView)->model;
-    QSignalSpy rootIndexChangedSpy(delegateModel, SIGNAL(rootIndexChanged()));
-    QVERIFY(rootIndexChangedSpy.isValid());
-
-    auto *model = listView->model().value<ResettableModel *>();
-    model->callBeginResetModel();
-    model->appendData();
-    model->callEndResetModel();
-    // This is verifies that handleModelReset isn't called
-    // more than once during this process, since it unconditionally emits rootIndexChanged.
-    QCOMPARE(rootIndexChangedSpy.count(), 1);
-
-    QTRY_VERIFY_WITH_TIMEOUT(listView->itemAtIndex(0), 100);
-    firstDelegateItem = listView->itemAtIndex(0);
-    QVERIFY(firstDelegateItem);
-    QCOMPARE(firstDelegateItem->property("display").toString(), "Item 0");
+    QTRY_VERIFY(root->property("success").toBool());
 }
 
 void tst_QQmlDelegateModel::valueWithoutCallingObjectFirst_data()
-- 
2.46.1