Add QFile::moveToTrash, which moves a file to the trash

Due to the nature of QFile just operating on a file path, this also
works for paths that are actually directories.

The test covers files from different locations on which this
operation should typically succeed, but tries to handle the case
where trashing files will fail because of the file system
structure.

On Windows 7, running the test will open a confirmation dialog as
the implementation of IFileOperation doesn't respect the various
flags. This might depend on the specific Windows 7 patch level,
and the option to always use SHFileOperation on that platform needs
to be evaluated further.

[ChangeLog][QtCore][QFile] Introduce QFile::moveToTrash to allow
applications to move files to the trash.

Change-Id: I45019040c25b30f7db293b6933c63aca2f319514
Fixes: QTBUG-47703
Reviewed-by: Vitaly Fanaskov <vitaly.fanaskov@qt.io>

1 files changed, 143 insertions, 0 deletions

diff --git a/tests/auto/corelib/io/qfile/tst_qfile.cpp b/tests/auto/corelib/io/qfile/tst_qfile.cpp
index 16a30af892..b065e1f10f 100644
--- a/tests/auto/corelib/io/qfile/tst_qfile.cpp
+++ b/tests/auto/corelib/io/qfile/tst_qfile.cpp
@@ -279,6 +279,9 @@ private slots:
 
     void reuseQFile();
 
+    void moveToTrash_data();
+    void moveToTrash();
+
 private:
 #ifdef BUILTIN_TESTDATA
     QSharedPointer<QTemporaryDir> m_dataDir;
@@ -3672,5 +3675,145 @@ void tst_QFile::reuseQFile()
     }
 }
 
+void tst_QFile::moveToTrash_data()
+{
+    QTest::addColumn<QString>("source");
+    QTest::addColumn<bool>("create");
+    QTest::addColumn<bool>("result");
+
+    if (QOperatingSystemVersion::current() <= QOperatingSystemVersion::Windows7)
+        QSKIP("Windows 7 insists on showing a confirmation dialog", SkipAll);
+
+    // success cases
+    {
+        QTemporaryFile temp;
+        QVERIFY(temp.open());
+        QTest::newRow("temporary file") << temp.fileName() << true << true;
+    }
+    {
+        QTemporaryDir tempDir;
+        tempDir.setAutoRemove(false);
+        QTest::newRow("temporary dir")
+            << tempDir.path() + QLatin1Char('/')
+            << true << true;
+    }
+    {
+        QTemporaryDir homeDir(QDir::homePath() + QLatin1String("/XXXXXX"));
+        homeDir.setAutoRemove(false);
+        QTemporaryFile homeFile(homeDir.path()
+                              + QLatin1String("/tst_qfile-XXXXXX"));
+        homeFile.open();
+        QTest::newRow("home file")
+            << homeFile.fileName()
+            << true << true;
+
+        QTest::newRow("home dir")
+            << homeDir.path() + QLatin1Char('/')
+            << true << true;
+    }
+    QTest::newRow("relative") << QStringLiteral("tst_qfile_moveToTrash.tmp") << true << true;
+
+    // failure cases
+    QTest::newRow("root") << QDir::rootPath() << false << false;
+    QTest::newRow("no-such-file") << QString::fromLatin1("no/such/file") << false << false;
+}
+
+void tst_QFile::moveToTrash()
+{
+    QFETCH(QString, source);
+    QFETCH(bool, create);
+    QFETCH(bool, result);
+
+    /* This test makes assumptions about the file system layout
+       which might be wrong - moveToTrash may fail if the file lives
+       on a file system that is different from the home file system, and
+       has no .Trash directory.
+    */
+    const bool mayFail = QStorageInfo(source) != QStorageInfo(QDir::home());
+
+#if defined(Q_OS_WINRT)
+    QSKIP("WinRT does not have a trash", SkipAll);
+#endif
+
+    auto ensureFile = [](const QString &source, bool create) {
+        if (QFileInfo::exists(source) || !create)
+            return;
+        if (source.endsWith(QLatin1Char('/'))) {
+            QDir::root().mkdir(source);
+            QFile file(source + QLatin1String("test"));
+            if (!file.open(QIODevice::WriteOnly))
+                QSKIP("Couldn't create directory with file");
+        } else {
+            QFile sourceFile(source);
+            QVERIFY2(sourceFile.open(QFile::WriteOnly | QFile::Text), qPrintable(sourceFile.errorString()));
+            sourceFile.close();
+        }
+    };
+    auto cleanupFile = [source, create]() {
+        if (!QFileInfo::exists(source) || !create)
+            return;
+        if (source.endsWith(QLatin1Char('/'))) {
+            QDir(source).removeRecursively();
+        } else {
+            QFile sourceFile(source);
+            sourceFile.remove();
+        }
+    };
+    // non-static version
+    {
+        ensureFile(source, create);
+        QFile sourceFile(source);
+        const bool success = sourceFile.moveToTrash();
+
+        // tolerate moveToTrash failing
+        if (result && !success && mayFail)
+            result = false;
+
+        if (result) {
+            // if any of the test fails, we still want to remove the file
+            auto onFailure = qScopeGuard(cleanupFile);
+            QVERIFY2(success, qPrintable(sourceFile.errorString()));
+            QCOMPARE(sourceFile.error(), QFile::NoError);
+            QVERIFY(source != sourceFile.fileName());
+            if (!sourceFile.fileName().isEmpty()) {
+                QVERIFY2(sourceFile.exists(), qPrintable(sourceFile.fileName()));
+                // remove file/dir in trash as well, don't fill disk
+                if (source.endsWith(QLatin1Char('/')))
+                    QDir(sourceFile.fileName()).removeRecursively();
+                else
+                    sourceFile.remove();
+            }
+        } else {
+            QVERIFY(!success);
+            QVERIFY(!sourceFile.errorString().isEmpty());
+            QCOMPARE(source, sourceFile.fileName());
+        }
+    }
+
+    // don't retry
+    if (mayFail)
+        return;
+
+    // static version
+    {
+        ensureFile(source, create);
+        QString pathInTrash;
+        const bool success = QFile::moveToTrash(source, &pathInTrash);
+        QCOMPARE(success, result);
+        if (result) {
+            auto onFailure = qScopeGuard(cleanupFile);
+            QVERIFY(source != pathInTrash);
+            if (!pathInTrash.isEmpty()) {
+                // remove file/dir in trash as well, don't fill disk
+                QVERIFY2(QFile::exists(pathInTrash), qPrintable(pathInTrash));
+                if (source.endsWith(QLatin1Char('/')))
+                    QDir(pathInTrash).removeRecursively();
+                else
+                    QFile::remove(pathInTrash);
+            }
+        }
+    }
+}
+
 QTEST_MAIN(tst_QFile)
 #include "tst_qfile.moc"