QmlDesigner: fix a rarely happen crash

It was difficult to reproduce, but happen regular while importing
something from design tools.

Task-number: QTCREATORBUG-23707
Change-Id: I93e8c8cf9d44ecf20f5754ae48a0599f056a8610
Reviewed-by: Thomas Hartmann <thomas.hartmann@qt.io>

4 files changed, 13 insertions, 5 deletions

diff --git a/src/plugins/qmldesigner/components/itemlibrary/itemlibrarymodel.cpp b/src/plugins/qmldesigner/components/itemlibrary/itemlibrarymodel.cpp
index 3714f2bf07..7f2558220f 100644
--- a/src/plugins/qmldesigner/components/itemlibrary/itemlibrarymodel.cpp
+++ b/src/plugins/qmldesigner/components/itemlibrary/itemlibrarymodel.cpp
@@ -34,6 +34,7 @@
 #include <nodemetainfo.h>
 
 #include <utils/algorithm.h>
+#include <utils/qtcassert.h>
 
 #include <QVariant>
 #include <QMetaProperty>
@@ -290,13 +291,15 @@ void ItemLibraryModel::addRoleNames()
 
 void ItemLibraryModel::sortSections()
 {
+    int nullPointerSectionCount = m_sections.removeAll(QPointer<ItemLibrarySection>());
+    QTC_ASSERT(nullPointerSectionCount == 0,;);
     auto sectionSort = [](ItemLibrarySection *first, ItemLibrarySection *second) {
         return QString::localeAwareCompare(first->sortingName(), second->sortingName()) < 1;
     };
 
     std::sort(m_sections.begin(), m_sections.end(), sectionSort);
 
-    foreach (ItemLibrarySection *itemLibrarySection, m_sections)
+    for (auto itemLibrarySection : m_sections)
         itemLibrarySection->sortItems();
 }
 
diff --git a/src/plugins/qmldesigner/components/itemlibrary/itemlibrarysection.cpp b/src/plugins/qmldesigner/components/itemlibrary/itemlibrarysection.cpp
index 994f72f184..b1db4d128e 100644
--- a/src/plugins/qmldesigner/components/itemlibrary/itemlibrarysection.cpp
+++ b/src/plugins/qmldesigner/components/itemlibrary/itemlibrarysection.cpp
@@ -74,7 +74,7 @@ bool ItemLibrarySection::updateSectionVisibility(const QString &searchText, bool
 
     *changed = false;
 
-    foreach(ItemLibraryItem *itemLibraryItem, m_sectionEntries.items()) {
+    for (auto itemLibraryItem : m_sectionEntries.items()) {
         bool itemVisible = itemLibraryItem->itemName().toLower().contains(searchText)
                 || itemLibraryItem->typeName().toLower().contains(searchText);
 
diff --git a/src/plugins/qmldesigner/components/itemlibrary/itemlibrarysectionmodel.cpp b/src/plugins/qmldesigner/components/itemlibrary/itemlibrarysectionmodel.cpp
index 5a60dd1eb7..6f7e57763c 100644
--- a/src/plugins/qmldesigner/components/itemlibrary/itemlibrarysectionmodel.cpp
+++ b/src/plugins/qmldesigner/components/itemlibrary/itemlibrarysectionmodel.cpp
@@ -27,6 +27,8 @@
 
 #include "itemlibraryitem.h"
 
+#include <utils/qtcassert.h>
+
 #include <QDebug>
 
 namespace QmlDesigner {
@@ -79,13 +81,15 @@ void ItemLibrarySectionModel::addItem(ItemLibraryItem *element)
     element->setVisible(true);
 }
 
-const QList<ItemLibraryItem *> &ItemLibrarySectionModel::items() const
+const QList<QPointer<ItemLibraryItem>> &ItemLibrarySectionModel::items() const
 {
     return m_itemList;
 }
 
 void ItemLibrarySectionModel::sortItems()
 {
+    int nullPointerSectionCount = m_itemList.removeAll(QPointer<ItemLibraryItem>());
+    QTC_ASSERT(nullPointerSectionCount == 0,;);
     auto itemSort = [](ItemLibraryItem *first, ItemLibraryItem *second) {
         return QString::localeAwareCompare(first->itemName(), second->itemName()) < 1;
     };
diff --git a/src/plugins/qmldesigner/components/itemlibrary/itemlibrarysectionmodel.h b/src/plugins/qmldesigner/components/itemlibrary/itemlibrarysectionmodel.h
index 6e1771a52f..4995e0c8c5 100644
--- a/src/plugins/qmldesigner/components/itemlibrary/itemlibrarysectionmodel.h
+++ b/src/plugins/qmldesigner/components/itemlibrary/itemlibrarysectionmodel.h
@@ -28,6 +28,7 @@
 #include "itemlibrarymodel.h"
 
 #include <QObject>
+#include <QPointer>
 
 namespace QmlDesigner {
 
@@ -47,7 +48,7 @@ public:
 
     void addItem(ItemLibraryItem *item);
 
-    const QList<ItemLibraryItem *> &items() const;
+    const QList<QPointer<ItemLibraryItem> > &items() const;
 
     void sortItems();
     void resetModel();
@@ -56,7 +57,7 @@ private: // functions
     void addRoleNames();
 
 private: // variables
-    QList<ItemLibraryItem*> m_itemList;
+    QList<QPointer<ItemLibraryItem>> m_itemList;
     QHash<int, QByteArray> m_roleNames;
 };