QFileIconEngine: Remove reference to QFileIconProvider

Keeping the reference may end up in a crash if a created
QIcon outlives the QFileIconProvider and we then try to
generate a pixmap.

The reference is not necessary since the options are queried
only when creating the icon, so they can be saved in the icon
provider.

Task-number: QTBUG-46755
Change-Id: I5c60887c2ed39030a2a20298ff10fd652189e4e7
Reviewed-by: Timur Pocheptsov <Timur.Pocheptsov@digia.com>
Reviewed-by: Marc Mutz <marc.mutz@kdab.com>
Reviewed-by: Morten Johan Sørvig <morten.sorvig@theqtcompany.com>

2 files changed, 22 insertions, 6 deletions

diff --git a/src/widgets/itemviews/qfileiconprovider.cpp b/src/widgets/itemviews/qfileiconprovider.cpp
index 5bab531290..051cb8e7cc 100644
--- a/src/widgets/itemviews/qfileiconprovider.cpp
+++ b/src/widgets/itemviews/qfileiconprovider.cpp
@@ -63,8 +63,8 @@ static bool isCacheable(const QFileInfo &fi);
 class QFileIconEngine : public QPixmapIconEngine
 {
 public:
-    QFileIconEngine(const QFileIconProvider *fip, const QFileInfo &info)
-        : QPixmapIconEngine(), m_fileIconProvider(fip), m_fileInfo(info)
+    QFileIconEngine(const QFileInfo &info, QFileIconProvider::Options opts)
+        : QPixmapIconEngine(), m_fileInfo(info), m_fipOpts(opts)
     { }
 
     QPixmap pixmap(const QSize &size, QIcon::Mode mode, QIcon::State state) Q_DECL_OVERRIDE
@@ -90,7 +90,7 @@ public:
         }
 
         QPlatformTheme::IconOptions iconOptions;
-        if (m_fileIconProvider->options() & QFileIconProvider::DontUseCustomDirectoryIcons)
+        if (m_fipOpts & QFileIconProvider::DontUseCustomDirectoryIcons)
             iconOptions |= QPlatformTheme::DontUseCustomDirectoryIcons;
 
         pixmap = theme->fileIconPixmap(m_fileInfo, size, iconOptions);
@@ -152,8 +152,8 @@ public:
     }
 
 private:
-    const QFileIconProvider *m_fileIconProvider;
     QFileInfo m_fileInfo;
+    QFileIconProvider::Options m_fipOpts;
 };
 
 
@@ -346,8 +346,7 @@ QIcon QFileIconProviderPrivate::getIcon(const QFileInfo &fi) const
     if (sizes.isEmpty())
         return QIcon();
 
-    Q_Q(const QFileIconProvider);
-    return QIcon(new QFileIconEngine(q, fi));
+    return QIcon(new QFileIconEngine(fi, options));
 }
 
 /*!
diff --git a/tests/auto/widgets/itemviews/qfileiconprovider/tst_qfileiconprovider.cpp b/tests/auto/widgets/itemviews/qfileiconprovider/tst_qfileiconprovider.cpp
index 0bc972d0cb..fba83a24c7 100644
--- a/tests/auto/widgets/itemviews/qfileiconprovider/tst_qfileiconprovider.cpp
+++ b/tests/auto/widgets/itemviews/qfileiconprovider/tst_qfileiconprovider.cpp
@@ -58,6 +58,8 @@ private slots:
 
     void type_data();
     void type();
+
+    void taskQTBUG_46755_QFileIconEngine_crash();
 };
 
 // Subclass that exposes the protected functions.
@@ -167,6 +169,21 @@ void tst_QFileIconProvider::type()
     QVERIFY(!provider.type(info).isEmpty());
 }
 
+static QIcon getIcon()
+{
+    QFileIconProvider fip;
+    return fip.icon(QDir::currentPath());
+}
+
+void tst_QFileIconProvider::taskQTBUG_46755_QFileIconEngine_crash()
+{
+    const QIcon &icon = getIcon();
+    foreach (const QSize &size, icon.availableSizes())
+        icon.pixmap(size);
+
+    // No crash, all good.
+}
+
 QTEST_MAIN(tst_QFileIconProvider)
 #include "tst_qfileiconprovider.moc"