Fix font inheritance for popups

1) First of all, Popup's QObject-parent depends on the way the Popup
is declared in QML, or what is passed as a parent to createObject()
when creating dynamic instances. For example:

 - Popup becomes a QObject child of of the contentItem:

    ApplicationWindow {
        Popup { }
    }

- Popup becomes a QObject child of the window:

    ApplicationWindow {
        Item {
            Popup { }
        }
    }

- Popup becomes a QObject child of the specified parent:

    ApplicationWindow {
        Component {
            id: component
            Popup { }
        }
        Component.onComplete: component.createObject(overlay)
    }

Since QQuickWindow and QQuickView did not set the QObject-parent
of their contentItem and rootObject, respectively, we had troubles
finding popup instances, because window->findChildren<QQuickPopup>()
and window->contentItem()->findChildren<QQuickPopup>() would produce
inconsistent results. This has been fixed in qtdeclarative commit
af6655885, so now we can use window->findChildren() reliably.

2) Popups inherit font from the associated window, not the parent item.
It was wrong to call resolveFont() in setParentItem(), because the
parent item might not change even though the associated window does.
The piece of code was moved to setWindow() instead.

3) QQuickPopupItemPrivate::resolveFont() did not propagate the
default font at all when the font was resolved before being associated
to a window.

4) After the above fixes had been applied, to ensure that popups always
inherit fonts and propagate them down to children as appropriate, we
got a new test failure in tst_controls::Popup::test_font() indicating
that there were extra font change notifiers triggered at creation time.
This was fixed by associating "top-level" popups with the window as
soon as they are appended to ApplicationWindow's default property,
instead of waiting until the popup is complete and then doing a lookup
in the parent hierarchy.

Task-number: QTBUG-61114
Change-Id: I6185c76d50835cb7a06b03db0a3ac9ddad64bdd3
Reviewed-by: Mitch Curtis <mitch.curtis@qt.io>

1 files changed, 289 insertions, 0 deletions

diff --git a/tests/auto/font/tst_font.cpp b/tests/auto/font/tst_font.cpp
new file mode 100644
index 00000000..6f04a8c0
--- /dev/null
+++ b/tests/auto/font/tst_font.cpp
@@ -0,0 +1,289 @@
+/****************************************************************************
+**
+** Copyright (C) 2017 The Qt Company Ltd.
+** Contact: http://www.qt.io/licensing/
+**
+** This file is part of the test suite of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL3$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see http://www.qt.io/terms-conditions. For further
+** information use the contact form at http://www.qt.io/contact-us.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 3 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPLv3 included in the
+** packaging of this file. Please review the following information to
+** ensure the GNU Lesser General Public License version 3 requirements
+** will be met: https://www.gnu.org/licenses/lgpl.html.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 2.0 or later as published by the Free
+** Software Foundation and appearing in the file LICENSE.GPL included in
+** the packaging of this file. Please review the following information to
+** ensure the GNU General Public License version 2.0 requirements will be
+** met: http://www.gnu.org/licenses/gpl-2.0.html.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include <QtTest/qtest.h>
+#include "../shared/visualtestutil.h"
+
+#include <QtGui/qfont.h>
+#include <QtGui/qpa/qplatformtheme.h>
+#include <QtGui/private/qguiapplication_p.h>
+#include <QtQml/qqmlengine.h>
+#include <QtQml/qqmlcomponent.h>
+#include <QtQuickTemplates2/private/qquickapplicationwindow_p.h>
+#include <QtQuickTemplates2/private/qquickcontrol_p.h>
+#include <QtQuickTemplates2/private/qquickpopup_p.h>
+#include <QtQuickControls2/private/qquickproxytheme_p.h>
+
+using namespace QQuickVisualTestUtil;
+
+class tst_font : public QQmlDataTest
+{
+    Q_OBJECT
+
+private slots:
+    void font_data();
+    void font();
+
+    void inheritance_data();
+    void inheritance();
+
+    void defaultFont_data();
+    void defaultFont();
+};
+
+void tst_font::font_data()
+{
+    QTest::addColumn<QString>("testFile");
+    QTest::addColumn<QFont>("expectedFont");
+
+    QTest::newRow("Control") << "font-control-default.qml" << QFont();
+    QTest::newRow("AppWindow") << "font-appwindow-default.qml" << QFont();
+    QTest::newRow("Popup") << "font-popup-default.qml" << QFont();
+
+    QFont customFont;
+    customFont.setCapitalization(QFont::AllUppercase);
+    customFont.setFamily("Courier");
+    customFont.setItalic(true);
+    customFont.setPixelSize(60);
+    customFont.setStrikeOut(true);
+    customFont.setUnderline(true);
+    customFont.setWeight(QFont::DemiBold);
+
+    QTest::newRow("Control:custom") << "font-control-custom.qml" << customFont;
+    QTest::newRow("AppWindow:custom") << "font-appwindow-custom.qml" << customFont;
+    QTest::newRow("Popup:custom") << "font-popup-custom.qml" << customFont;
+}
+
+void tst_font::font()
+{
+    QFETCH(QString, testFile);
+    QFETCH(QFont, expectedFont);
+
+    QQmlEngine engine;
+    QQmlComponent component(&engine);
+    component.loadUrl(testFileUrl(testFile));
+
+    QScopedPointer<QObject> object(component.create());
+    QVERIFY2(!object.isNull(), qPrintable(component.errorString()));
+
+    QVariant var = object->property("font");
+    QVERIFY(var.isValid());
+
+    QFont actualFont = var.value<QFont>();
+    QCOMPARE(actualFont, expectedFont);
+}
+
+void tst_font::inheritance_data()
+{
+    QTest::addColumn<QString>("testFile");
+
+    QTest::newRow("Control") << "inheritance-control.qml";
+    QTest::newRow("Child Control") << "inheritance-childcontrol.qml";
+    QTest::newRow("Dynamic Control") << "inheritance-dynamiccontrol.qml";
+    QTest::newRow("Dynamic Child Control") << "inheritance-dynamicchildcontrol.qml";
+
+    QTest::newRow("Popup") << "inheritance-popup.qml";
+    QTest::newRow("Child Popup") << "inheritance-childpopup.qml";
+    QTest::newRow("Dynamic Popup") << "inheritance-dynamicpopup.qml";
+    QTest::newRow("Dynamic Child Popup") << "inheritance-dynamicchildpopup.qml";
+}
+
+void tst_font::inheritance()
+{
+    QFETCH(QString, testFile);
+
+    QQmlEngine engine;
+    QQmlComponent component(&engine);
+    component.loadUrl(testFileUrl(testFile));
+
+    QScopedPointer<QQuickApplicationWindow> window(qobject_cast<QQuickApplicationWindow *>(component.create()));
+    QVERIFY2(!window.isNull(), qPrintable(component.errorString()));
+
+    QObject *control = window->property("control").value<QObject *>();
+    QObject *child = window->property("child").value<QObject *>();
+    QObject *grandChild = window->property("grandChild").value<QObject *>();
+    QVERIFY(control && child && grandChild);
+
+    QCOMPARE(window->font(), QFont());
+
+    QCOMPARE(control->property("font").value<QFont>(), QFont());
+    QCOMPARE(child->property("font").value<QFont>(), QFont());
+    QCOMPARE(grandChild->property("font").value<QFont>(), QFont());
+
+    QFont childFont;
+    childFont.setFamily("Arial");
+    childFont.setPixelSize(80);
+    childFont.setItalic(true);
+    child->setProperty("font", childFont);
+    QCOMPARE(child->property("font").value<QFont>(), childFont);
+    QCOMPARE(grandChild->property("font").value<QFont>(), childFont);
+
+    QFont grandChildFont(childFont);
+    grandChildFont.setFamily("Times New Roman");
+    grandChildFont.setUnderline(true);
+    grandChild->setProperty("font", grandChildFont);
+    QCOMPARE(child->property("font").value<QFont>(), childFont);
+    QCOMPARE(grandChild->property("font").value<QFont>(), grandChildFont);
+
+    QFont windowFont;
+    windowFont.setWeight(QFont::Thin);
+    window->setFont(windowFont);
+    QCOMPARE(window->font(), windowFont);
+    QCOMPARE(control->property("font").value<QFont>(), windowFont);
+
+    childFont.setWeight(QFont::Thin);
+    QCOMPARE(child->property("font").value<QFont>(), childFont);
+
+    grandChildFont.setWeight(QFont::Thin);
+    QCOMPARE(grandChild->property("font").value<QFont>(), grandChildFont);
+
+    child->setProperty("font", QVariant());
+    QCOMPARE(child->property("font").value<QFont>(), windowFont);
+    QCOMPARE(grandChild->property("font").value<QFont>(), grandChildFont);
+
+    grandChild->setProperty("font", QVariant());
+    QCOMPARE(grandChild->property("font").value<QFont>(), windowFont);
+}
+
+class TestFontTheme : public QQuickProxyTheme
+{
+public:
+    TestFontTheme(QPlatformTheme *theme) : QQuickProxyTheme(theme)
+    {
+        std::fill(fonts, fonts + QPlatformTheme::NFonts, static_cast<QFont *>(0));
+
+        for (int i = QPlatformTheme::SystemFont; i < QPlatformTheme::NFonts; ++i) {
+            QFont font = QFont();
+            font.setPixelSize(i + 10);
+            fonts[i] = new QFont(font);
+        }
+
+        QGuiApplicationPrivate::platform_theme = this;
+    }
+
+    const QFont *font(Font type = SystemFont) const override
+    {
+        return fonts[type];
+    }
+
+private:
+    QFont *fonts[QPlatformTheme::NFonts];
+};
+
+Q_DECLARE_METATYPE(QPlatformTheme::Font)
+
+void tst_font::defaultFont_data()
+{
+    QTest::addColumn<QString>("control");
+    QTest::addColumn<QPlatformTheme::Font>("fontType");
+
+    QTest::newRow("AbstractButton") << "AbstractButton" << QPlatformTheme::SystemFont;
+    QTest::newRow("ApplicationWindow") << "ApplicationWindow" << QPlatformTheme::SystemFont;
+    QTest::newRow("Button") << "Button" << QPlatformTheme::PushButtonFont;
+    QTest::newRow("CheckBox") << "CheckBox" << QPlatformTheme::CheckBoxFont;
+    QTest::newRow("CheckDelegate") << "CheckDelegate" << QPlatformTheme::ListViewFont;
+    QTest::newRow("ComboBox") << "ComboBox" << QPlatformTheme::ComboMenuItemFont;
+    QTest::newRow("Container") << "Container" << QPlatformTheme::SystemFont;
+    QTest::newRow("Control") << "Control" << QPlatformTheme::SystemFont;
+    QTest::newRow("Dial") << "Dial" << QPlatformTheme::SystemFont;
+    QTest::newRow("Dialog") << "Dialog" << QPlatformTheme::SystemFont;
+    QTest::newRow("DialogButtonBox") << "DialogButtonBox" << QPlatformTheme::SystemFont;
+    QTest::newRow("Drawer") << "Drawer" << QPlatformTheme::SystemFont;
+    QTest::newRow("Frame") << "Frame" << QPlatformTheme::SystemFont;
+    QTest::newRow("GroupBox") << "GroupBox" << QPlatformTheme::GroupBoxTitleFont;
+    QTest::newRow("ItemDelegate") << "ItemDelegate" << QPlatformTheme::ItemViewFont;
+    QTest::newRow("Label") << "Label" << QPlatformTheme::LabelFont;
+    QTest::newRow("Menu") << "Menu" << QPlatformTheme::MenuFont;
+    QTest::newRow("MenuItem") << "MenuItem" << QPlatformTheme::MenuItemFont;
+    QTest::newRow("MenuSeparator") << "MenuSeparator" << QPlatformTheme::SystemFont;
+    QTest::newRow("Page") << "Page" << QPlatformTheme::SystemFont;
+    QTest::newRow("Pane") << "Pane" << QPlatformTheme::SystemFont;
+    QTest::newRow("Popup") << "Popup" << QPlatformTheme::SystemFont;
+    QTest::newRow("ProgressBar") << "ProgressBar" << QPlatformTheme::SystemFont;
+    QTest::newRow("RadioButton") << "RadioButton" << QPlatformTheme::RadioButtonFont;
+    QTest::newRow("RadioDelegate") << "RadioDelegate" << QPlatformTheme::ListViewFont;
+    QTest::newRow("RangeSlider") << "RangeSlider" << QPlatformTheme::SystemFont;
+    QTest::newRow("RoundButton") << "RoundButton" << QPlatformTheme::PushButtonFont;
+    QTest::newRow("ScrollBar") << "ScrollBar" << QPlatformTheme::SystemFont;
+    QTest::newRow("ScrollIndicator") << "ScrollIndicator" << QPlatformTheme::SystemFont;
+    QTest::newRow("Slider") << "Slider" << QPlatformTheme::SystemFont;
+    QTest::newRow("SpinBox") << "SpinBox" << QPlatformTheme::EditorFont;
+    QTest::newRow("SwipeDelegate") << "SwipeDelegate" << QPlatformTheme::ListViewFont;
+    QTest::newRow("Switch") << "Switch" << QPlatformTheme::SystemFont; // ### TODO: add QPlatformTheme::SwitchFont
+    QTest::newRow("SwitchDelegate") << "SwitchDelegate" << QPlatformTheme::ListViewFont;
+    QTest::newRow("TabBar") << "TabBar" << QPlatformTheme::SystemFont;
+    QTest::newRow("TabButton") << "TabButton" << QPlatformTheme::TabButtonFont;
+    QTest::newRow("TextArea") << "TextArea" << QPlatformTheme::EditorFont;
+    QTest::newRow("TextField") << "TextField" << QPlatformTheme::EditorFont;
+    QTest::newRow("ToolBar") << "ToolBar" << QPlatformTheme::SystemFont;
+    QTest::newRow("ToolButton") << "ToolButton" << QPlatformTheme::ToolButtonFont;
+    QTest::newRow("ToolSeparator") << "ToolSeparator" << QPlatformTheme::SystemFont;
+    QTest::newRow("ToolTip") << "ToolTip" << QPlatformTheme::TipLabelFont;
+    QTest::newRow("Tumbler") << "Tumbler" << QPlatformTheme::SystemFont;
+}
+
+void tst_font::defaultFont()
+{
+    QFETCH(QString, control);
+    QFETCH(QPlatformTheme::Font, fontType);
+
+    TestFontTheme theme(QGuiApplicationPrivate::platform_theme);
+
+    QQmlEngine engine;
+    QQmlComponent component(&engine);
+    component.setData(QString("import QtQuick.Controls 2.2; %1 { }").arg(control).toUtf8(), QUrl());
+
+    QScopedPointer<QObject> object(component.create());
+    QVERIFY2(!object.isNull(), qPrintable(component.errorString()));
+
+    QVariant var = object->property("font");
+    QVERIFY(var.isValid());
+
+    const QFont *expectedFont = theme.font(fontType);
+    QVERIFY(expectedFont);
+
+    QFont actualFont = var.value<QFont>();
+
+    if (actualFont != *expectedFont) {
+        qDebug() << QTest::currentDataTag() << actualFont << *expectedFont;
+    }
+
+    QCOMPARE(actualFont, *expectedFont);
+}
+
+QTEST_MAIN(tst_font)
+
+#include "tst_font.moc"