QAbstractFileEngine: make {begin,end}EntryList() return a unique_ptr

Makes ownership clearer.

Change-Id: Ibb57ca900ef30b16d48964a977e997ba6705248b
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>
Reviewed-by: Qt CI Bot <qt_ci_bot@qt-project.org>

src/corelib/doc/snippets/code/src_corelib_io_qabstractfileengine.cpp

@@ -38,10 +38,10 @@ QAbstractSocketEngine *ZipEngineHandler::create(const QString &fileName) const
 
 
 //! [2]
-QAbstractFileEngineIterator *
+QAbstractFileEngine::IteratorUniquePtr
 CustomFileEngine::beginEntryList(QDir::Filters filters, const QStringList &filterNames)
 {
-    return new CustomFileEngineIterator(filters, filterNames);
+    return std::make_unique<CustomFileEngineIterator>(filters, filterNames);
 }
 //! [2]
 

src/corelib/io/qabstractfileengine.cpp

@@ -890,6 +890,14 @@ bool QAbstractFileEngine::cloneTo(QAbstractFileEngine *target)
     Synonym for QAbstractFileEngineIterator.
 */
 
+/*!
+    \typedef QAbstractFileEngine::IteratorUniquePtr
+    \since 6.8
+
+    Synonym for std::unique_ptr<Iterator> (that is a
+    std::unique_ptr<QAbstractFileEngineIterator>).
+*/
+
 /*!
     Constructs a QAbstractFileEngineIterator, using the entry filters \a
     filters, and wildcard name filters \a nameFilters.
@@ -1019,20 +1027,19 @@ QFileInfo QAbstractFileEngineIterator::currentFileInfo() const
 */
 
 /*!
-    Returns an instance of a QAbstractFileEngineIterator using \a filters for
+    Returns a QAbstractFileEngine::IteratorUniquePtr, that uses \a filters
-    entry filtering and \a filterNames for name filtering. This function is
+    for entry filtering and \a filterNames for name filtering. This function
-    called by QDirListing to initiate directory iteration.
+    is called by QDirListing to initiate directory iteration.
-
-    QDirListing takes ownership of the returned instance, and deletes it when
-    it's done.
 
     \sa QDirListing
 */
-QAbstractFileEngine::Iterator *QAbstractFileEngine::beginEntryList(QDir::Filters filters, const QStringList &filterNames)
+QAbstractFileEngine::IteratorUniquePtr
+QAbstractFileEngine::beginEntryList(QDir::Filters filters,
+                                    const QStringList &filterNames)
 {
     Q_UNUSED(filters);
     Q_UNUSED(filterNames);
-    return nullptr;
+    return {};
 }
 
 /*!

src/corelib/io/qabstractfileengine_p.h

@@ -19,6 +19,7 @@
 #include "QtCore/qfile.h"
 #include "QtCore/qdir.h"
 
+#include <memory>
 #include <optional>
 
 #ifdef open
@@ -126,8 +127,11 @@ public:
     bool unmap(uchar *ptr);
 
     typedef QAbstractFileEngineIterator Iterator;
-    virtual Iterator *beginEntryList(QDir::Filters filters, const QStringList &filterNames);
+    using IteratorUniquePtr = std::unique_ptr<Iterator>;
-    virtual Iterator* endEntryList() { return nullptr; }
+
+    virtual IteratorUniquePtr
+    beginEntryList(QDir::Filters filters, const QStringList &filterNames);
+    virtual IteratorUniquePtr endEntryList() { return {}; }
 
     virtual qint64 read(char *data, qint64 maxlen);
     virtual qint64 readLine(char *data, qint64 maxlen);

src/corelib/io/qdirlisting.cpp

@@ -165,10 +165,9 @@ void QDirListingPrivate::pushDirectory(QDirEntryInfo &entryInfo)
 
     if (engine) {
         engine->setFileName(path);
-        QAbstractFileEngineIterator *it = engine->beginEntryList(filters, nameFilters);
+        if (auto it = engine->beginEntryList(filters, nameFilters)) {
-        if (it) {
             it->setPath(path);
-            fileEngineIterators.emplace(FEngineIteratorPtr(it));
+            fileEngineIterators.emplace(std::move(it));
         } else {
             // No iterator; no entry list.
         }

src/corelib/io/qfsfileengine.cpp

@@ -791,9 +791,10 @@ qint64 QFSFileEnginePrivate::writeFdFh(const char *data, qint64 len)
 /*!
     \internal
 */
-QAbstractFileEngine::Iterator *QFSFileEngine::beginEntryList(QDir::Filters filters, const QStringList &filterNames)
+QAbstractFileEngine::IteratorUniquePtr
+QFSFileEngine::beginEntryList(QDir::Filters filters, const QStringList &filterNames)
 {
-    return new QFSFileEngineIterator(filters, filterNames);
+    return std::make_unique<QFSFileEngineIterator>(filters, filterNames);
 }
 
 #endif // QT_NO_FILESYSTEMITERATOR

src/corelib/io/qfsfileengine_iterator.cpp

@@ -10,8 +10,8 @@
 QT_BEGIN_NAMESPACE
 
 QFSFileEngineIterator::QFSFileEngineIterator(QDir::Filters filters, const QStringList &filterNames)
-    : QAbstractFileEngineIterator(filters, filterNames)
+    : QAbstractFileEngineIterator(filters, filterNames),
-    , done(false)
+      done(false)
 {
 }
 

src/corelib/io/qfsfileengine_p.h

@@ -82,7 +82,8 @@ public:
     int handle() const override;
 
 #ifndef QT_NO_FILESYSTEMITERATOR
-    Iterator *beginEntryList(QDir::Filters filters, const QStringList &filterNames) override;
+    IteratorUniquePtr beginEntryList(QDir::Filters filters,
+                                     const QStringList &filterNames) override;
 #endif
 
     qint64 read(char *data, qint64 maxlen) override;

src/corelib/io/qresource.cpp

@@ -1534,11 +1534,10 @@ QDateTime QResourceFileEngine::fileTime(FileTime time) const
 /*!
     \internal
 */
-QAbstractFileEngine::Iterator *QResourceFileEngine::beginEntryList(QDir::Filters filters,
+QAbstractFileEngine::IteratorUniquePtr
-                                                                   const QStringList &filterNames)
+QResourceFileEngine::beginEntryList(QDir::Filters filters, const QStringList &filterNames)
 {
-    return new QResourceFileEngineIterator(filters, filterNames);
+    return std::make_unique<QResourceFileEngineIterator>(filters, filterNames);
-
 }
 
 bool QResourceFileEngine::extension(Extension extension, const ExtensionOption *option, ExtensionReturn *output)

src/corelib/io/qresource_p.h

@@ -49,7 +49,8 @@ public:
 
     QDateTime fileTime(FileTime time) const override;
 
-    Iterator *beginEntryList(QDir::Filters filters, const QStringList &filterNames) override;
+    IteratorUniquePtr beginEntryList(QDir::Filters filters,
+                                     const QStringList &filterNames) override;
 
     bool extension(Extension extension, const ExtensionOption *option = nullptr, ExtensionReturn *output = nullptr) override;
     bool supportsExtension(Extension extension) const override;

src/plugins/platforms/android/androidcontentfileengine.cpp

@@ -248,10 +248,10 @@ QString AndroidContentFileEngine::fileName(FileName f) const
     return QString();
 }
 
-QAbstractFileEngine::Iterator *AndroidContentFileEngine::beginEntryList(QDir::Filters filters,
+QAbstractFileEngine::IteratorUniquePtr
-                                                                    const QStringList &filterNames)
+AndroidContentFileEngine::beginEntryList(QDir::Filters filters, const QStringList &filterNames)
 {
-    return new AndroidContentFileEngineIterator(filters, filterNames);
+    return std::make_unique<AndroidContentFileEngineIterator>(filters, filterNames);
 }
 
 AndroidContentFileEngineHandler::AndroidContentFileEngineHandler() = default;

src/plugins/platforms/android/androidcontentfileengine.h

@@ -30,7 +30,8 @@ public:
     QDateTime fileTime(FileTime time) const override;
     FileFlags fileFlags(FileFlags type = FileInfoAll) const override;
     QString fileName(FileName file = DefaultName) const override;
-    QAbstractFileEngine::Iterator *beginEntryList(QDir::Filters filters, const QStringList &filterNames) override;
+    IteratorUniquePtr beginEntryList(QDir::Filters filters,
+                                     const QStringList &filterNames) override;
 
 private:
     void closeNativeFileDescriptor();

src/plugins/platforms/android/qandroidassetsfileenginehandler.cpp

@@ -367,10 +367,11 @@ public:
         m_assetsInfoCache.insert(m_fileName, newAssetInfoPtr);
     }
 
-    Iterator *beginEntryList(QDir::Filters filters, const QStringList &filterNames) override
+    IteratorUniquePtr
+    beginEntryList(QDir::Filters filters, const QStringList &filterNames) override
     {
         if (m_assetInfo && m_assetInfo->type == AssetItem::Type::Folder)
-            return new AndroidAbstractFileEngineIterator(filters, filterNames, m_fileName);
+            return std::make_unique<AndroidAbstractFileEngineIterator>(filters, filterNames, m_fileName);
         return nullptr;
     }
 

src/plugins/platforms/ios/optional/nsphotolibrarysupport/qiosfileengineassetslibrary.h

@@ -29,7 +29,8 @@ public:
     void setFileName(const QString &file) override;
 
 #ifndef QT_NO_FILESYSTEMITERATOR
-    Iterator *beginEntryList(QDir::Filters filters, const QStringList &filterNames) override;
+    IteratorUniquePtr beginEntryList(QDir::Filters filters,
+                                     const QStringList &filterNames) override;
 #endif
 
     void setError(QFile::FileError error, const QString &str) { QAbstractFileEngine::setError(error, str); }

src/plugins/platforms/ios/optional/nsphotolibrarysupport/qiosfileengineassetslibrary.mm

@@ -440,10 +440,10 @@ void QIOSFileEngineAssetsLibrary::setFileName(const QString &file)
 
 #ifndef QT_NO_FILESYSTEMITERATOR
 
-QAbstractFileEngine::Iterator *QIOSFileEngineAssetsLibrary::beginEntryList(
+QAbstractFileEngine::IteratorUniquePtr
-        QDir::Filters filters, const QStringList &filterNames)
+QIOSFileEngineAssetsLibrary::beginEntryList(QDir::Filters filters, const QStringList &filterNames)
 {
-    return new QIOSFileEngineIteratorAssetsLibrary(filters, filterNames);
+    return std::make_unique<QIOSFileEngineIteratorAssetsLibrary>(filters, filterNames);
 }
 
 QT_END_NAMESPACE

tests/auto/corelib/io/qabstractfileengine/tst_qabstractfileengine.cpp

@@ -459,9 +459,11 @@ public:
         : QFSFileEngine(fileName)
     {
     }
-    Iterator *beginEntryList(QDir::Filters filters, const QStringList &filterNames) override
+
+    IteratorUniquePtr
+    beginEntryList(QDir::Filters filters, const QStringList &filterNames) override
     {
-        return new Iterator(filters, filterNames);
+        return std::make_unique<Iterator>(filters, filterNames);
     }
     FileFlags fileFlags(FileFlags type) const override
     {

tests/auto/corelib/io/qdiriterator/tst_qdiriterator.cpp

@@ -436,8 +436,9 @@ public:
         : QFSFileEngine(fileName)
     { }
 
-    QAbstractFileEngineIterator *beginEntryList(QDir::Filters, const QStringList &) override
+    IteratorUniquePtr
-    { return 0; }
+    beginEntryList(QDir::Filters, const QStringList &) override
+    { return nullptr; }
 };
 
 class EngineWithNoIteratorHandler : public QAbstractFileEngineHandler

tests/auto/corelib/io/qdirlisting/tst_qdirlisting.cpp

@@ -421,8 +421,8 @@ public:
         : QFSFileEngine(fileName)
     { }
 
-    QAbstractFileEngineIterator *beginEntryList(QDir::Filters, const QStringList &) override
+    IteratorUniquePtr beginEntryList(QDir::Filters, const QStringList &) override
-    { return 0; }
+    { return nullptr; }
 };
 
 class EngineWithNoIteratorHandler : public QAbstractFileEngineHandler