diff options
| -rw-r--r-- | src/gui/image/qimagewriter.cpp | 49 | ||||
| -rw-r--r-- | tests/auto/gui/image/qimagewriter/tst_qimagewriter.cpp | 24 |
2 files changed, 59 insertions, 14 deletions
diff --git a/src/gui/image/qimagewriter.cpp b/src/gui/image/qimagewriter.cpp index 900093b51b..8dd5fdd111 100644 --- a/src/gui/image/qimagewriter.cpp +++ b/src/gui/image/qimagewriter.cpp @@ -245,6 +245,8 @@ class QImageWriterPrivate public: QImageWriterPrivate(QImageWriter *qq); + bool canWriteHelper(); + // device QByteArray format; QIODevice *device; @@ -282,6 +284,31 @@ QImageWriterPrivate::QImageWriterPrivate(QImageWriter *qq) q = qq; } +bool QImageWriterPrivate::canWriteHelper() +{ + if (!device) { + imageWriterError = QImageWriter::DeviceError; + errorString = QT_TRANSLATE_NOOP(QImageWriter, + QLatin1String("Device is not set")); + return false; + } + if (!device->isOpen()) + device->open(QIODevice::WriteOnly); + if (!device->isWritable()) { + imageWriterError = QImageWriter::DeviceError; + errorString = QT_TRANSLATE_NOOP(QImageWriter, + QLatin1String("Device not writable")); + return false; + } + if (!handler && (handler = createWriteHandlerHelper(device, format)) == 0) { + imageWriterError = QImageWriter::UnsupportedFormatError; + errorString = QT_TRANSLATE_NOOP(QImageWriter, + QLatin1String("Unsupported image format")); + return false; + } + return true; +} + /*! Constructs an empty QImageWriter object. Before writing, you must call setFormat() to set an image format, then setDevice() or @@ -561,21 +588,15 @@ void QImageWriter::setText(const QString &key, const QString &text) */ bool QImageWriter::canWrite() const { - if (d->device && !d->handler && (d->handler = createWriteHandlerHelper(d->device, d->format)) == 0) { - d->imageWriterError = QImageWriter::UnsupportedFormatError; - d->errorString = QT_TRANSLATE_NOOP(QImageWriter, - QLatin1String("Unsupported image format")); - return false; + if (QFile *file = qobject_cast<QFile *>(d->device)) { + const bool remove = !file->isOpen() && !file->exists(); + const bool result = d->canWriteHelper(); + if (!result && remove) + file->remove(); + return result; } - if (d->device && !d->device->isOpen()) - d->device->open(QIODevice::WriteOnly); - if (!d->device || !d->device->isWritable()) { - d->imageWriterError = QImageWriter::DeviceError; - d->errorString = QT_TRANSLATE_NOOP(QImageWriter, - QLatin1String("Device not writable")); - return false; - } - return true; + + return d->canWriteHelper(); } /*! diff --git a/tests/auto/gui/image/qimagewriter/tst_qimagewriter.cpp b/tests/auto/gui/image/qimagewriter/tst_qimagewriter.cpp index f1d0e227f6..b10b5704c3 100644 --- a/tests/auto/gui/image/qimagewriter/tst_qimagewriter.cpp +++ b/tests/auto/gui/image/qimagewriter/tst_qimagewriter.cpp @@ -50,6 +50,7 @@ #include <QImageWriter> #include <QPainter> #include <QSet> +#include <QTemporaryDir> #ifdef Q_OS_UNIX // for geteuid() # include <sys/types.h> @@ -84,6 +85,7 @@ private slots: void supportedMimeTypes(); void writeToInvalidDevice(); + void testCanWrite(); void supportsOption_data(); void supportsOption(); @@ -402,6 +404,28 @@ void tst_QImageWriter::writeToInvalidDevice() } } +void tst_QImageWriter::testCanWrite() +{ + { + // device is not set + QImageWriter writer; + QVERIFY(!writer.canWrite()); + QCOMPARE(writer.error(), QImageWriter::DeviceError); + } + + { + // check if canWrite won't leave an empty file + QTemporaryDir dir; + QVERIFY(dir.isValid()); + QString fileName(dir.path() + QLatin1String("/001.garble")); + QVERIFY(!QFileInfo(fileName).exists()); + QImageWriter writer(fileName); + QVERIFY(!writer.canWrite()); + QCOMPARE(writer.error(), QImageWriter::UnsupportedFormatError); + QVERIFY(!QFileInfo(fileName).exists()); + } +} + void tst_QImageWriter::supportsOption_data() { QTest::addColumn<QString>("fileName"); |