From 9145c173d29cef3a1f2eb0ccc28a6288455a46b2 Mon Sep 17 00:00:00 2001
From: David Faure <faure@kde.org>
Date: Wed, 10 Jan 2018 18:08:57 +0100
Subject: [PATCH] KRearrangeColumnsProxyModel: fix crash when there's no source
 model

---
 autotests/krearrangecolumnsproxymodeltest.cpp | 10 ++++++++++
 src/krearrangecolumnsproxymodel.cpp           |  6 ++++++
 2 files changed, 16 insertions(+)

diff --git a/autotests/krearrangecolumnsproxymodeltest.cpp b/autotests/krearrangecolumnsproxymodeltest.cpp
index 7ff621f..a84c8a2 100644
--- a/autotests/krearrangecolumnsproxymodeltest.cpp
+++ b/autotests/krearrangecolumnsproxymodeltest.cpp
@@ -65,6 +65,16 @@ private Q_SLOTS:
         // showModel(&mod);
     }
 
+    void shouldShowNothingIfNoSourceModel()
+    {
+        // Given a rearrange-columns proxy with no source model
+        KRearrangeColumnsProxyModel pm;
+
+        // Then the proxy should show nothing (no columns selected)
+        QCOMPARE(pm.rowCount(), 0);
+        QCOMPARE(pm.columnCount(), 0);
+    }
+
     void shouldShowNothingIfNoColumnSelection()
     {
         // Given a rearrange-columns proxy
diff --git a/src/krearrangecolumnsproxymodel.cpp b/src/krearrangecolumnsproxymodel.cpp
index 5925809..3f5eede 100644
--- a/src/krearrangecolumnsproxymodel.cpp
+++ b/src/krearrangecolumnsproxymodel.cpp
@@ -44,12 +44,18 @@ void KRearrangeColumnsProxyModel::setSourceColumns(const QVector<int> &columns)
 int KRearrangeColumnsProxyModel::columnCount(const QModelIndex &parent) const
 {
     Q_UNUSED(parent);
+    if (!sourceModel()) {
+        return 0;
+    }
     return d_ptr->m_sourceColumns.count();
 }
 
 int KRearrangeColumnsProxyModel::rowCount(const QModelIndex &parent) const
 {
     Q_ASSERT(parent.isValid() ? parent.model() == this : true);
+    if (!sourceModel()) {
+        return 0;
+    }
     // The parent in the source model is on column 0, whatever swapping we are doing
     const QModelIndex sourceParent = mapToSource(parent).sibling(parent.row(), 0);
     return sourceModel()->rowCount(sourceParent);