tdf#136704 sw autofmt: prevent crash if no nextNode

The second GetNextNode() was a nullptr
that was being dereferenced.

Now, when enter is pressed after some text followed by a colon,
that line is made into a heading3, and the new blank line is
properly using the text body paragraph style.

Change-Id: If10dc85e490ac57fc150b3d541f5033dfd5293bb
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/109413
Tested-by: Jenkins
Reviewed-by: Justin Luth <justin_luth@sil.org>
Reviewed-by: Michael Stahl <michael.stahl@allotropia.de>
(cherry picked from commit fea7b531a4c9e8326a644cccc26325b16585675a)
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/109519

1 files changed, 7 insertions, 4 deletions

diff --git a/sw/source/core/edit/autofmt.cxx b/sw/source/core/edit/autofmt.cxx
index bd0cfc1972fb..2a40b90d448f 100644
--- a/sw/source/core/edit/autofmt.cxx
+++ b/sw/source/core/edit/autofmt.cxx
@@ -1896,11 +1896,14 @@ void SwAutoFormat::BuildHeadLine( sal_uInt16 nLvl )
         JoinPrevPara();
 
         DeleteLeadingTrailingBlanks( true, false );
-        const SwTextFrame *const pNextFrame = GetNextNode(false);
-        (void)DeleteJoinCurNextPara(pNextFrame, true);
-
+        const SwTextFrame* pNextFrame = GetNextNode(false);
+        if (pNextFrame->GetNext())
+        {
+            (void)DeleteJoinCurNextPara(pNextFrame, true);
+            pNextFrame = GetNextNode(false);
+        }
         m_aDelPam.DeleteMark();
-        m_aDelPam.GetPoint()->nNode = *GetNextNode(false)->GetTextNodeForParaProps();
+        m_aDelPam.GetPoint()->nNode = *pNextFrame->GetTextNodeForParaProps();
         m_aDelPam.GetPoint()->nContent.Assign( m_aDelPam.GetContentNode(), 0 );
         m_pDoc->SetTextFormatColl( m_aDelPam, &rNxtColl );
     }