Add a context manager for override cursors

[ChangeLog][PySide] A context manager for override cursors
has been added. It is now possible to write code like:
with QApplication.setOverrideCursor(Qt.WaitCursor):...

Change-Id: I443ce82389b48656f21c98df17d97e1b3b3323b5
Reviewed-by: Qt CI Bot <qt_ci_bot@qt-project.org>
Reviewed-by: Cristian Maureira-Fredes <cristian.maureira-fredes@qt.io>

8 files changed, 125 insertions, 33 deletions

diff --git a/examples/widgets/mainwindows/application/application.py b/examples/widgets/mainwindows/application/application.py
index 3ec9344cb..b22f2b7cb 100644
--- a/examples/widgets/mainwindows/application/application.py
+++ b/examples/widgets/mainwindows/application/application.py
@@ -232,27 +232,25 @@ class MainWindow(QMainWindow):
             return
 
         inf = QTextStream(file)
-        QApplication.setOverrideCursor(Qt.WaitCursor)
-        self._text_edit.setPlainText(inf.readAll())
-        QApplication.restoreOverrideCursor()
+        with QApplication.setOverrideCursor(Qt.WaitCursor):
+            self._text_edit.setPlainText(inf.readAll())
 
         self.set_current_file(fileName)
         self.statusBar().showMessage("File loaded", 2000)
 
     def save_file(self, fileName):
         error = None
-        QApplication.setOverrideCursor(Qt.WaitCursor)
-        file = QSaveFile(fileName)
-        if file.open(QFile.WriteOnly | QFile.Text):
-            outf = QTextStream(file)
-            outf << self._text_edit.toPlainText()
-            if not file.commit():
+        with QApplication.setOverrideCursor(Qt.WaitCursor):
+            file = QSaveFile(fileName)
+            if file.open(QFile.WriteOnly | QFile.Text):
+                outf = QTextStream(file)
+                outf << self._text_edit.toPlainText()
+                if not file.commit():
+                    reason = file.errorString()
+                    error = f"Cannot write file {fileName}:\n{reason}."
+            else:
                 reason = file.errorString()
-                error = f"Cannot write file {fileName}:\n{reason}."
-        else:
-            reason = file.errorString()
-            error = f"Cannot open file {fileName}:\n{reason}."
-        QApplication.restoreOverrideCursor()
+                error = f"Cannot open file {fileName}:\n{reason}."
 
         if error:
             QMessageBox.warning(self, "Application", error)
diff --git a/examples/widgets/mainwindows/dockwidgets/dockwidgets.py b/examples/widgets/mainwindows/dockwidgets/dockwidgets.py
index 61b1dd781..db08895d6 100644
--- a/examples/widgets/mainwindows/dockwidgets/dockwidgets.py
+++ b/examples/widgets/mainwindows/dockwidgets/dockwidgets.py
@@ -145,9 +145,8 @@ class MainWindow(QMainWindow):
             return
 
         out = QTextStream(file)
-        QApplication.setOverrideCursor(Qt.WaitCursor)
-        out << self._text_edit.toHtml()
-        QApplication.restoreOverrideCursor()
+        with QApplication.setOverrideCursor(Qt.WaitCursor):
+            out << self._text_edit.toHtml()
 
         self.statusBar().showMessage(f"Saved '{filename}'", 2000)
 
diff --git a/examples/widgets/mainwindows/mdi/mdi.py b/examples/widgets/mainwindows/mdi/mdi.py
index a6ea6284d..06d80b1a1 100644
--- a/examples/widgets/mainwindows/mdi/mdi.py
+++ b/examples/widgets/mainwindows/mdi/mdi.py
@@ -81,9 +81,8 @@ class MdiChild(QTextEdit):
             return False
 
         instr = QTextStream(file)
-        QApplication.setOverrideCursor(Qt.WaitCursor)
-        self.setPlainText(instr.readAll())
-        QApplication.restoreOverrideCursor()
+        with QApplication.setOverrideCursor(Qt.WaitCursor):
+            self.setPlainText(instr.readAll())
 
         self.set_current_file(fileName)
 
@@ -106,18 +105,17 @@ class MdiChild(QTextEdit):
 
     def save_file(self, fileName):
         error = None
-        QApplication.setOverrideCursor(Qt.WaitCursor)
-        file = QSaveFile(fileName)
-        if file.open(QFile.WriteOnly | QFile.Text):
-            outstr = QTextStream(file)
-            outstr << self.toPlainText()
-            if not file.commit():
+        with QApplication.setOverrideCursor(Qt.WaitCursor):
+            file = QSaveFile(fileName)
+            if file.open(QFile.WriteOnly | QFile.Text):
+                outstr = QTextStream(file)
+                outstr << self.toPlainText()
+                if not file.commit():
+                    reason = file.errorString()
+                    error = f"Cannot write file {fileName}:\n{reason}."
+            else:
                 reason = file.errorString()
-                error = f"Cannot write file {fileName}:\n{reason}."
-        else:
-            reason = file.errorString()
-            error = f"Cannot open file {fileName}:\n{reason}."
-        QApplication.restoreOverrideCursor()
+                error = f"Cannot open file {fileName}:\n{reason}."
 
         if error:
             QMessageBox.warning(self, "MDI", error)
diff --git a/sources/pyside6/PySide6/QtGui/CMakeLists.txt b/sources/pyside6/PySide6/QtGui/CMakeLists.txt
index 5bdb38253..2c95c71af 100644
--- a/sources/pyside6/PySide6/QtGui/CMakeLists.txt
+++ b/sources/pyside6/PySide6/QtGui/CMakeLists.txt
@@ -189,6 +189,7 @@ ${QtGui_GEN_DIR}/qtexttable_wrapper.cpp
 ${QtGui_GEN_DIR}/qtexttablecell_wrapper.cpp
 ${QtGui_GEN_DIR}/qtexttablecellformat_wrapper.cpp
 ${QtGui_GEN_DIR}/qtexttableformat_wrapper.cpp
+${QtGui_GEN_DIR}/qtguihelper_qoverridecursorguard_wrapper.cpp
 ${QtGui_GEN_DIR}/qtoolbarchangeevent_wrapper.cpp
 ${QtGui_GEN_DIR}/qtouchevent_wrapper.cpp
 ${QtGui_GEN_DIR}/qtransform_wrapper.cpp
@@ -233,5 +234,7 @@ create_pyside_module(NAME QtGui
                      TYPESYSTEM_NAME ${QtGui_BINARY_DIR}/typesystem_gui.xml
                      DROPPED_ENTRIES QtGui_DROPPED_ENTRIES)
 
-install(FILES ${pyside6_SOURCE_DIR}/qpytextobject.h DESTINATION include/PySide6/QtGui/)
+install(FILES ${pyside6_SOURCE_DIR}/qpytextobject.h
+              ${pyside6_SOURCE_DIR}/qtguihelper.h
+        DESTINATION include/PySide6/QtGui/)
 
diff --git a/sources/pyside6/PySide6/QtGui/QtGui_global.post.h.in b/sources/pyside6/PySide6/QtGui/QtGui_global.post.h.in
index 6d3a3eeac..deb7cf805 100644
--- a/sources/pyside6/PySide6/QtGui/QtGui_global.post.h.in
+++ b/sources/pyside6/PySide6/QtGui/QtGui_global.post.h.in
@@ -1 +1,2 @@
 #include "qpytextobject.h"  // PySide class
+#include <qtguihelper.h>
diff --git a/sources/pyside6/PySide6/QtGui/typesystem_gui_common.xml b/sources/pyside6/PySide6/QtGui/typesystem_gui_common.xml
index 70edaa30c..6010af37f 100644
--- a/sources/pyside6/PySide6/QtGui/typesystem_gui_common.xml
+++ b/sources/pyside6/PySide6/QtGui/typesystem_gui_common.xml
@@ -2666,7 +2666,13 @@
     <add-function signature="exec_()" return-type="int">
         <inject-code file="../glue/qtgui.cpp" snippet="qguiapplication-exec"/>
     </add-function>
-
+    <modify-function signature="setOverrideCursor(const QCursor&amp;)">
+        <modify-argument index="return">
+            <replace-type modified-type="QtGuiHelper::QOverrideCursorGuard*"/>
+        </modify-argument>
+        <inject-code class="target" position="end" file="../glue/qtgui.cpp"
+                     snippet="qguiapplication-setoverridecursor"/>
+    </modify-function>
   </object-type>
 
   <object-type name="QOpenGLContext">
@@ -3098,4 +3104,16 @@
       </modify-argument>
     </modify-function>
   </object-type>
+
+  <namespace-type name="QtGuiHelper" visible="no">
+      <object-type name="QOverrideCursorGuard" copyable="no">
+      <add-function signature="__enter__()" return-type="QOverrideCursorGuard">
+          <inject-code file="../glue/qtcore.cpp" snippet="default-enter"/>
+      </add-function>
+      <add-function signature="__exit__(PyObject*,PyObject*,PyObject*)">
+          <inject-code>%CPPSELF.restoreOverrideCursor();</inject-code>
+      </add-function>
+      </object-type>
+  </namespace-type>
+
 </typesystem>
diff --git a/sources/pyside6/PySide6/glue/qtgui.cpp b/sources/pyside6/PySide6/glue/qtgui.cpp
index f7bf2c57e..b312180b7 100644
--- a/sources/pyside6/PySide6/glue/qtgui.cpp
+++ b/sources/pyside6/PySide6/glue/qtgui.cpp
@@ -654,6 +654,12 @@ if (!PyTuple_SetItem(empty, 0, PyList_New(0))) {
 }
 // @snippet qguiapplication-2
 
+// @snippet qguiapplication-setoverridecursor
+auto *cppResult = new QtGuiHelper::QOverrideCursorGuard();
+%PYARG_0 = %CONVERTTOPYTHON[QtGuiHelper::QOverrideCursorGuard*](cppResult);
+Shiboken::Object::getOwnership(%PYARG_0); // Ensure the guard is removed
+// @snippet qguiapplication-setoverridecursor
+
 // @snippet qscreen-grabWindow
 WId id = %1;
 %RETURN_TYPE retval = %CPPSELF.%FUNCTION_NAME(id, %2, %3, %4, %5);
diff --git a/sources/pyside6/PySide6/qtguihelper.h b/sources/pyside6/PySide6/qtguihelper.h
new file mode 100644
index 000000000..4fee6c53e
--- /dev/null
+++ b/sources/pyside6/PySide6/qtguihelper.h
@@ -0,0 +1,69 @@
+/****************************************************************************
+**
+** Copyright (C) 2022 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of Qt for Python.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** 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.
+**
+** 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.LGPL3 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-3.0.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 (at your option) the GNU General
+** Public license version 3 or any later version approved by the KDE Free
+** Qt Foundation. The licenses are as published by the Free Software
+** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3
+** included in the packaging of this file. Please review the following
+** information to ensure the GNU General Public License requirements will
+** be met: https://www.gnu.org/licenses/gpl-2.0.html and
+** https://www.gnu.org/licenses/gpl-3.0.html.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#ifndef QTGUIHELPER_H
+#define QTGUIHELPER_H
+
+#include <QtGui/QGuiApplication>
+
+namespace QtGuiHelper {
+
+    class QOverrideCursorGuard
+    {
+    public:
+        Q_DISABLE_COPY_MOVE(QOverrideCursorGuard)
+
+        QOverrideCursorGuard() = default;
+        ~QOverrideCursorGuard() { restoreOverrideCursor(); }
+
+        void restoreOverrideCursor()
+        {
+            if (m_guard) {
+                QGuiApplication::restoreOverrideCursor();
+                m_guard = false;
+            }
+        }
+
+    private:
+        bool m_guard = true;
+    };
+
+} // namespace QtGuiHelper
+
+#endif // QTGUIHELPER_H