Update test cases for change in default size policy

The size policy of items updated as part of task QTBUG-117597. This patch
adds an autotest for default size policies.

Task-number: QTBUG-117597
Change-Id: Ibc84b2d462885d1d31313040905e74e5bb072373
Reviewed-by: Jan Arve Sæther <jan-arve.saether@qt.io>
(cherry picked from commit ef30b93682d7f82d6cbe03fb32cb775c99a26910)
Reviewed-by: Qt Cherry-pick Bot <cherrypick_bot@qt-project.org>

2 files changed, 116 insertions, 5 deletions

diff --git a/tests/auto/quick/qquicklayouts/data/tst_rowlayout.qml b/tests/auto/quick/qquicklayouts/data/tst_rowlayout.qml
index a93775a6d0..99da499e08 100644
--- a/tests/auto/quick/qquicklayouts/data/tst_rowlayout.qml
+++ b/tests/auto/quick/qquicklayouts/data/tst_rowlayout.qml
@@ -3,6 +3,7 @@
 
 import QtQuick
 import QtTest
+import QtQuick.Controls
 import QtQuick.Layouts
 import "LayoutHelperLibrary.js" as LayoutHelpers
 
@@ -24,6 +25,13 @@ Item {
             return [item.x, item.y, item.width, item.height];
         }
 
+        function cleanup() {
+            if (LayoutSetup.useDefaultSizePolicy) {
+                LayoutSetup.useDefaultSizePolicy = false
+                compare(LayoutSetup.useDefaultSizePolicy, false)
+            }
+        }
+
         Component {
             id: rectangle_Component
             Rectangle {
@@ -1620,8 +1628,8 @@ Item {
             compare(rootItem.maxWidth, 66)
 
             // Should not trigger a binding loop
-            verify(!BindingLoopDetector.bindingLoopDetected, "Detected binding loop")
-            BindingLoopDetector.reset()
+            verify(!LayoutSetup.bindingLoopDetected, "Detected binding loop")
+            LayoutSetup.resetBindingLoopDetectedFlag()
         }
 
 
@@ -1661,5 +1669,105 @@ Item {
             wait(0)                         // process the scheduled delete and actually invoke the dtor
             data.func(layout)               // call a function that might ultimately access the deleted item (but shouldn't)
         }
+
+        //---------------------------
+        // Default layout size policy
+        Component {
+            id: defaultLayoutComp
+            Item {
+                id: rootItem
+                width: 110
+                height: 100
+                // Check default layout size policy
+                RowLayout {
+                    spacing: 0
+                    anchors.fill: parent
+                    // Rectangle item - SizePolicy { Horizontal: Fixed;  Vertical: Fixed }
+                    Rectangle {}
+                    // Button item - SizePolicy { Horizontal: Preferred; Vertical: Fixed }
+                    Button {}
+                    // Frame item - SizePolicy { Horizontal: Preferred; Vertical: Preferred }
+                    Frame {}
+                }
+            }
+        }
+
+        function test_defaultLayoutSize() {
+            let rootItem = createTemporaryObject(defaultLayoutComp, container)
+            waitForRendering(rootItem)
+
+            let rowLayout = rootItem.children[0]
+
+            // Test default size policy disabled by default
+            compare(LayoutSetup.useDefaultSizePolicy, false)
+
+            let defaultButtonWidth = rowLayout.children[1].width
+            let defaultFrameWidth = rowLayout.children[2].width
+
+            // Enable attached properties for items and check its size
+            {
+                rowLayout.children[0].Layout.fillWidth = true
+                rowLayout.children[0].Layout.fillHeight = true
+                rowLayout.children[1].Layout.fillWidth = true
+                rowLayout.children[1].Layout.fillHeight = true
+                rowLayout.children[2].Layout.fillWidth = true
+                rowLayout.children[2].Layout.fillHeight = true
+                waitForRendering(rowLayout)
+                let isAbovePreferred = rowLayout.width >= rowLayout.implicitWidth
+                // Removing rectangle as width & implicitWidth be zero always, which makes validation of no use
+                for (let i = 1; i < rowLayout.children.length; i++) {
+                    compare(rowLayout.children[i].width >= rowLayout.children[i].implicitWidth, isAbovePreferred)
+                    compare(rowLayout.children[i].height, rowLayout.height)
+                }
+            }
+
+            // Destroy existing object
+            rootItem.destroy()
+
+            // Enable default size policy
+            LayoutSetup.useDefaultSizePolicy = true
+            compare(LayoutSetup.useDefaultSizePolicy, true)
+            rootItem = createTemporaryObject(defaultLayoutComp, container)
+            waitForRendering(rootItem)
+            rowLayout = rootItem.children[0]
+
+            // The default size policy would stretch button and frame accordingly
+            {
+                verify(Math.abs(rowLayout.width - (rowLayout.children[0].width + rowLayout.children[1].width + rowLayout.children[2].width)) <= 1)
+                compare(rowLayout.children[1].width < rowLayout.children[2].width, rowLayout.children[1].implicitWidth < rowLayout.children[2].implicitWidth)
+                compare(rowLayout.children[1].height, rowLayout.children[1].implicitHeight)
+                compare(rowLayout.children[2].height, rowLayout.height)
+            }
+
+            // Change the width and height of the root item to see layout size change
+            // Since default size policy for button and frame are Preferred, these items should
+            // stretch
+            {
+                let szDefaultButtonWidth = rowLayout.children[1].width
+                let szDefaultFrameWidth = rowLayout.children[2].width
+
+                rootItem.width = 210
+                rootItem.height = 200
+                waitForRendering(rootItem)
+                verify(rowLayout.children[1].width > szDefaultButtonWidth)
+                compare(rowLayout.children[1].height, rowLayout.children[1].implicitHeight)
+                verify(rowLayout.children[2].width > szDefaultFrameWidth)
+                compare(rowLayout.children[2].height, rowLayout.height)
+            }
+
+            // Disable size policies through attached properties and check item size
+            {
+                rowLayout.children[1].Layout.fillWidth = false
+                rowLayout.children[2].Layout.fillWidth = false
+                rowLayout.children[2].Layout.fillHeight = false
+                waitForRendering(rowLayout)
+                compare(rowLayout.children[1].width, defaultButtonWidth)
+                compare(rowLayout.children[2].width, defaultFrameWidth)
+                for (let index = 1; index < rowLayout.children.length; index++)
+                    compare(rowLayout.children[index].height, rowLayout.children[index].implicitHeight)
+            }
+
+            rootItem.destroy()
+        }
     }
 }
diff --git a/tests/auto/quick/qquicklayouts/tst_qquicklayouts.cpp b/tests/auto/quick/qquicklayouts/tst_qquicklayouts.cpp
index 3c018a07bc..98b5e96486 100644
--- a/tests/auto/quick/qquicklayouts/tst_qquicklayouts.cpp
+++ b/tests/auto/quick/qquicklayouts/tst_qquicklayouts.cpp
@@ -8,20 +8,23 @@ class Setup : public QObject
 {
     Q_OBJECT
     Q_PROPERTY(bool bindingLoopDetected READ wasBindingLoopDetected FINAL)
+    Q_PROPERTY(bool useDefaultSizePolicy READ useDefaultSizePolicy WRITE setUseDefaultSizePolicy FINAL)
 
 public:
     Setup() {}
 
     bool wasBindingLoopDetected() const { return mBindingLoopDetected; }
 
+    bool useDefaultSizePolicy() const { return QCoreApplication::testAttribute(Qt::AA_QtQuickUseDefaultSizePolicy); }
+    void setUseDefaultSizePolicy(bool policy) { QCoreApplication::setAttribute(Qt::AA_QtQuickUseDefaultSizePolicy, policy); }
+
 public slots:
-    void reset() { mBindingLoopDetected = false; }
+    void resetBindingLoopDetectedFlag() { mBindingLoopDetected = false; }
 
     void qmlEngineAvailable(QQmlEngine *engine)
     {
         connect(engine, &QQmlEngine::warnings, this, &Setup::qmlWarnings);
-
-        qmlRegisterSingletonInstance("org.qtproject.Test", 1, 0, "BindingLoopDetector", this);
+        qmlRegisterSingletonInstance("org.qtproject.Test", 1, 0, "LayoutSetup", this);
     }
 
     void qmlWarnings(const QList<QQmlError> &warnings)