Implement moving of a single file system entry to the trash

This implements the operation for Windows, macOS, and Unix, for now
only as a private API (since QFileSystemEngine is private). This adds
the capability as a testable function; public API to be agreed on and
added in a separate commit.

The Unix implementation follows the freedesktop.org specification [1]
version 1.0.

[1] https://specifications.freedesktop.org/trash-spec/trashspec-1.0.html

On macOS and Windows, native APIs are used, with each having some
limitations:

* on macOS, the file in the trash won't have a "put back" option,
  as we don't use Finder automation, for the reasons provided in the
  comments
* on Windows, we might not be able to use the modern IFileOperation
  API, e.g. if Qt is built with mingw which doesn't seem to provide
  the interface definition; the fallback doesn't provide access to
  the file name in the trash

The test case creates files and directories, and moves them to the
trash. As part of the cleanup routine, it deletes all file system
entries created. If run on Windows without IFileOperations support,
this will add a file in the trash for each test run, filling up
hard drive space.

Task-number: QTBUG-47703
Change-Id: I5f5f4e578be2f45d7da84f70a03acbe1a12a1231
Reviewed-by: Vitaly Fanaskov <vitaly.fanaskov@qt.io>

1 files changed, 79 insertions, 0 deletions

diff --git a/src/corelib/io/qfilesystemengine_mac.mm b/src/corelib/io/qfilesystemengine_mac.mm
new file mode 100644
index 0000000000..4bbce9e5f6
--- /dev/null
+++ b/src/corelib/io/qfilesystemengine_mac.mm
@@ -0,0 +1,79 @@
+/****************************************************************************
+**
+** Copyright (C) 2019 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the QtCore module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** 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.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include "qplatformdefs.h"
+#include "qfilesystemengine_p.h"
+#include "qfile.h"
+#include "qurl.h"
+
+#include <QtCore/private/qcore_mac_p.h>
+#include <CoreFoundation/CoreFoundation.h>
+
+QT_BEGIN_NAMESPACE
+
+/*
+    This implementation does not enable the "put back" option in Finder
+    for the trashed object. The only way to get this is to use Finder automation,
+    which would query the user for permission to access Finder using a modal,
+    blocking dialog - which we definitely can't have in a console application.
+
+    Using Finder would also play the trash sound, which we don't want either in
+    such a core API; applications that want that can play the sound themselves.
+*/
+//static
+bool QFileSystemEngine::moveFileToTrash(const QFileSystemEntry &source,
+                                        QFileSystemEntry &newLocation, QSystemError &error)
+{
+    QFileInfo info(source.filePath());
+    @autoreleasepool {
+        NSString *filepath = info.filePath().toNSString();
+        NSURL *fileurl = [NSURL fileURLWithPath:filepath isDirectory:info.isDir()];
+        NSURL *resultingUrl = nil;
+        NSError *nserror = nil;
+        NSFileManager *fm = [NSFileManager defaultManager];
+        if ([fm trashItemAtURL:fileurl resultingItemURL:&resultingUrl error:&nserror] != YES) {
+            error = QSystemError(nserror.code, QSystemError::NativeError);
+            return false;
+        }
+        newLocation = QFileSystemEntry(QUrl::fromNSURL(resultingUrl).path());
+    }
+    return true;
+}
+
+QT_END_NAMESPACE