Find custom styles from custom paths when set afterwards

This fixes the very frequent warning from plasmashell:
WARNING: Cannot find style "Plasma"

Change-Id: Ibe853e7b8b42adc2bce7c63a1505b27898ea5ffc
Reviewed-by: Mitch Curtis <mitch.curtis@qt.io>
Reviewed-by: J-P Nurmi <jpnurmi@qt.io>

2 files changed, 99 insertions, 0 deletions

diff --git a/tests/auto/customcontrolsstyle/QtQuick/Controls/Styles/Style/ButtonStyle.qml b/tests/auto/customcontrolsstyle/QtQuick/Controls/Styles/Style/ButtonStyle.qml
new file mode 100644
index 00000000..548c5641
--- /dev/null
+++ b/tests/auto/customcontrolsstyle/QtQuick/Controls/Styles/Style/ButtonStyle.qml
@@ -0,0 +1,61 @@
+/****************************************************************************
+**
+** Copyright (C) 2016 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the test suite of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:BSD$
+** 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 https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/contact-us.
+**
+** BSD License Usage
+** Alternatively, you may use this file under the terms of the BSD license
+** as follows:
+**
+** "Redistribution and use in source and binary forms, with or without
+** modification, are permitted provided that the following conditions are
+** met:
+**   * Redistributions of source code must retain the above copyright
+**     notice, this list of conditions and the following disclaimer.
+**   * Redistributions in binary form must reproduce the above copyright
+**     notice, this list of conditions and the following disclaimer in
+**     the documentation and/or other materials provided with the
+**     distribution.
+**   * Neither the name of The Qt Company Ltd nor the names of its
+**     contributors may be used to endorse or promote products derived
+**     from this software without specific prior written permission.
+**
+**
+** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+** "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+** LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+** A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+** OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+** SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+** LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+** DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+** THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+** (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+** OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE."
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+import QtQuick 2.4
+import QtQuick.Controls 1.4
+import QtQuick.Controls.Styles 1.4
+
+ButtonStyle {
+    background: Rectangle {
+        implicitWidth: 200
+        implicitHeight: 50
+        color: "blue"
+    }
+}
diff --git a/tests/auto/customcontrolsstyle/tst_customcontrolsstyle.cpp b/tests/auto/customcontrolsstyle/tst_customcontrolsstyle.cpp
index 99e8240e..8405c98b 100644
--- a/tests/auto/customcontrolsstyle/tst_customcontrolsstyle.cpp
+++ b/tests/auto/customcontrolsstyle/tst_customcontrolsstyle.cpp
@@ -47,6 +47,7 @@ private slots:
 
     void style_data();
     void style();
+    void changeStyle();
 };
 
 void tst_customcontrolsstyle::initTestCase()
@@ -105,6 +106,43 @@ void tst_customcontrolsstyle::style()
     }
 }
 
+// start with Base, switch to custom style later on (for a specific QML engine)
+void tst_customcontrolsstyle::changeStyle()
+{
+    qputenv("QT_QUICK_CONTROLS_1_STYLE", "Base");
+    qputenv("QML2_IMPORT_PATH", QFile::encodeName(directory()));
+
+    QQmlEngine engine;
+
+    QQmlComponent component(&engine, testFileUrl("TestComponent.qml"));
+    QTRY_COMPARE(component.status(), QQmlComponent::Ready);
+
+    QScopedPointer<QObject> object(component.create());
+    QVERIFY(object);
+
+    QCOMPARE(object->property("styleName").toString(), QString("Base"));
+
+    // Switch to "Style" custom style
+    QQmlComponent c(&engine);
+    c.setData("import QtQuick 2.1\n"
+        "import QtQuick.Controls 1.0\n"
+        "import QtQuick.Controls.Private 1.0\n"
+        "Item {"
+          "Component.onCompleted: {"
+            "Settings.styleName = \"Style\";"
+          "}"
+        "}", QUrl());
+    QObject *o = c.create();
+    o->deleteLater();
+
+    QCOMPARE(object->property("styleName").toString(), QString("Style"));
+    QMetaObject::invokeMethod(object.data(), "buttonStyleComponent");
+    QQuickWindow *window = qobject_cast<QQuickWindow*>(object.data());
+    QVERIFY(QTest::qWaitForWindowExposed(window));
+    QImage windowImage = window->grabWindow();
+    QCOMPARE(windowImage.pixel(0, 0), QColor(Qt::blue).rgb());
+}
+
 QTEST_MAIN(tst_customcontrolsstyle)
 
 #include "tst_customcontrolsstyle.moc"