tdf#134253 sw: fix SwUndoInserts::UndoImpl() if inserting before section

Somehow the clipboard is pasted before the SwSectionNode, which is the
first node in the body text.

The OSL_ENSURE( !bStartIsTextNode, "Oops, undo may be instable now." )
is triggered; the Undo must remove 2 SwTextNode in this case.

Because of the extra SwTextNode the indexes are off by 1 and this starts
to assert since commit 24fd14b387dca458a1b6e9415e936d26562ddb1e when
setting a fieldmark on a non-text node.

Change-Id: Ic52b0f4c7665994cadfe8f074bc4607c55352aa1
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/97887
Tested-by: Jenkins
Reviewed-by: Michael Stahl <michael.stahl@cib.de>

3 files changed, 37 insertions, 24 deletions

diff --git a/sw/inc/undobj.hxx b/sw/inc/undobj.hxx
index 60d219bc0109..d89ff20a0b57 100644
--- a/sw/inc/undobj.hxx
+++ b/sw/inc/undobj.hxx
@@ -254,7 +254,8 @@ class SwUndoInserts : public SwUndo, public SwUndRng, private SwUndoSaveContent
     std::unique_ptr<std::vector<SwFrameFormat*>> m_pFrameFormats;
     std::vector< std::shared_ptr<SwUndoInsLayFormat> > m_FlyUndos;
     std::unique_ptr<SwRedlineData> m_pRedlineData;
-    bool m_bStartWasTextNode;
+    int m_nDeleteTextNodes;
+
 protected:
     sal_uLong m_nNodeDiff;
     /// start of Content in UndoNodes for Redo
@@ -271,7 +272,7 @@ public:
 
     // Set destination range after reading.
     void SetInsertRange( const SwPaM&, bool bScanFlys = true,
-                         bool bSttWasTextNd = true );
+                         int nDeleteTextNodes = 1);
 
     static bool IsCreateUndoForNewFly(SwFormatAnchor const& rAnchor,
         sal_uLong const nStartNode, sal_uLong const nEndNode);
diff --git a/sw/source/core/doc/DocumentContentOperationsManager.cxx b/sw/source/core/doc/DocumentContentOperationsManager.cxx
index 4bb4325134d9..cbe579f18a0d 100644
--- a/sw/source/core/doc/DocumentContentOperationsManager.cxx
+++ b/sw/source/core/doc/DocumentContentOperationsManager.cxx
@@ -4734,7 +4734,7 @@ bool DocumentContentOperationsManager::CopyImplImpl(SwPaM& rPam, SwPosition& rPo
                           ( !bOneNode && !rPos.nContent.GetIndex() ) );
     bool bCopyBookmarks = true;
     bool bCopyPageSource  = false;
-    bool bStartIsTextNode = nullptr != pSttTextNd;
+    int nDeleteTextNodes = 0;
 
     // #i104585# copy outline num rule to clipboard (for ASCII filter)
     if (pDoc->IsClipBoard() && m_rDoc.GetOutlineNumRule())
@@ -4771,6 +4771,7 @@ bool DocumentContentOperationsManager::CopyImplImpl(SwPaM& rPam, SwPosition& rPo
     do {
         if( pSttTextNd )
         {
+            ++nDeleteTextNodes; // must be joined in Undo
             // Don't copy the beginning completely?
             if( !bCopyCollFormat || bColumnSel || pStt->nContent.GetIndex() )
             {
@@ -4880,7 +4881,7 @@ bool DocumentContentOperationsManager::CopyImplImpl(SwPaM& rPam, SwPosition& rPo
             else if( rPos.nContent.GetIndex() )
             {   // Insertion in the middle of a text node, it has to be split
                 // (and joined from undo)
-                bStartIsTextNode = true;
+                ++nDeleteTextNodes;
 
                 const sal_Int32 nContentEnd = pEnd->nContent.GetIndex();
                 {
@@ -4933,11 +4934,9 @@ bool DocumentContentOperationsManager::CopyImplImpl(SwPaM& rPam, SwPosition& rPo
 
                 // if we have to insert an extra text node
                 // at the destination, this node will be our new destination
-                // (text) node, and thus we set bStartisTextNode to true. This
-                // will ensure that this node will be deleted during Undo
-                // using JoinNext.
-                OSL_ENSURE( !bStartIsTextNode, "Oops, undo may be instable now." );
-                bStartIsTextNode = true;
+                // (text) node, and thus we increment nDeleteTextNodes. This
+                // will ensure that this node will be deleted during Undo.
+                ++nDeleteTextNodes; // must be deleted
             }
 
             const bool bEmptyDestNd = pDestTextNd->GetText().isEmpty();
@@ -5111,7 +5110,7 @@ bool DocumentContentOperationsManager::CopyImplImpl(SwPaM& rPam, SwPosition& rPo
     // If Undo is enabled, store the inserted area
     if (pDoc->GetIDocumentUndoRedo().DoesUndo())
     {
-        pUndo->SetInsertRange( *pCopyPam, true, bStartIsTextNode );
+        pUndo->SetInsertRange(*pCopyPam, true, nDeleteTextNodes);
     }
 
     if( pCpyRange )
diff --git a/sw/source/core/undo/untblk.cxx b/sw/source/core/undo/untblk.cxx
index 6df02f3f805d..f6e74518a8c3 100644
--- a/sw/source/core/undo/untblk.cxx
+++ b/sw/source/core/undo/untblk.cxx
@@ -63,9 +63,13 @@ GetFlysAnchoredAt(SwDoc & rDoc, sal_uLong const nSttNode)
 
 //note: parameter is SwPam just so we can init SwUndRng, the End is ignored!
 SwUndoInserts::SwUndoInserts( SwUndoId nUndoId, const SwPaM& rPam )
-    : SwUndo( nUndoId, rPam.GetDoc() ), SwUndRng( rPam ),
-    m_pTextFormatColl( nullptr ), m_pLastNodeColl(nullptr),
-    m_bStartWasTextNode( true ), m_nNodeDiff( 0 ), m_nSetPos( 0 )
+    : SwUndo( nUndoId, rPam.GetDoc() )
+    , SwUndRng( rPam )
+    , m_pTextFormatColl(nullptr)
+    , m_pLastNodeColl(nullptr)
+    , m_nDeleteTextNodes(1)
+    , m_nNodeDiff(0)
+    , m_nSetPos(0)
 {
     m_pHistory.reset( new SwHistory );
     SwDoc* pDoc = rPam.GetDoc();
@@ -74,6 +78,7 @@ SwUndoInserts::SwUndoInserts( SwUndoId nUndoId, const SwPaM& rPam )
     if( pTextNd )
     {
         m_pTextFormatColl = pTextNd->GetTextColl();
+        assert(m_pTextFormatColl);
         m_pHistory->CopyAttr( pTextNd->GetpSwpHints(), m_nSttNode,
                             0, pTextNd->GetText().getLength(), false );
         if( pTextNd->HasSwAttrSet() )
@@ -106,7 +111,7 @@ SwUndoInserts::SwUndoInserts( SwUndoId nUndoId, const SwPaM& rPam )
 //  Flys, anchored to any paragraph, but not first and last, are handled by DelContentIndex (see SwUndoInserts::UndoImpl) and are not stored in m_FlyUndos.
 
 void SwUndoInserts::SetInsertRange( const SwPaM& rPam, bool bScanFlys,
-                                    bool bSttIsTextNd )
+                                    int const nDeleteTextNodes)
 {
     const SwPosition* pTmpPos = rPam.End();
     m_nEndNode = pTmpPos->nNode.GetIndex();
@@ -121,11 +126,11 @@ void SwUndoInserts::SetInsertRange( const SwPaM& rPam, bool bScanFlys,
         m_nSttNode = pTmpPos->nNode.GetIndex();
         m_nSttContent = pTmpPos->nContent.GetIndex();
 
-        if( !bSttIsTextNd )      // if a table selection is added...
+        if (m_nDeleteTextNodes == 0) // if a table selection is added...
         {
             ++m_nSttNode;         // ... then the CopyPam is not fully correct
-            m_bStartWasTextNode = false;
         }
+        m_nDeleteTextNodes = nDeleteTextNodes;
     }
 
     // Fill m_FlyUndos with flys anchored to first and last paragraphs
@@ -309,8 +314,10 @@ void SwUndoInserts::UndoImpl(::sw::UndoRedoContext & rContext)
                     new SwNodeIndex(rDoc.GetNodes().GetEndOfContent()));
             MoveToUndoNds(rPam, m_pUndoNodeIndex.get());
 
-            if( !m_bStartWasTextNode )
+            if (m_nDeleteTextNodes == 0)
+            {
                 rPam.Move( fnMoveBackward, GoInContent );
+            }
         }
     }
 
@@ -321,15 +328,19 @@ void SwUndoInserts::UndoImpl(::sw::UndoRedoContext & rContext)
         if( !m_pTextFormatColl ) // if 0 than it's no TextNode -> delete
         {
             SwNodeIndex aDelIdx( rIdx );
-            ++rIdx;
-            SwContentNode* pCNd = rIdx.GetNode().GetContentNode();
-            rPam.GetPoint()->nContent.Assign( pCNd, pCNd ? pCNd->Len() : 0 );
-            rPam.SetMark();
+            assert(0 < m_nDeleteTextNodes && m_nDeleteTextNodes < 3);
+            for (int i = 0; i < m_nDeleteTextNodes; ++i)
+            {
+                rPam.Move(fnMoveForward, GoInNode);
+            }
             rPam.DeleteMark();
 
-            RemoveIdxRel(aDelIdx.GetIndex(), *rPam.GetPoint());
+            for (int i = 0; i < m_nDeleteTextNodes; ++i)
+            {
+                RemoveIdxRel(aDelIdx.GetIndex() + i, *rPam.GetPoint());
+            }
 
-            rDoc.GetNodes().Delete( aDelIdx );
+            rDoc.GetNodes().Delete( aDelIdx, m_nDeleteTextNodes );
         }
         else
         {
@@ -386,8 +397,10 @@ void SwUndoInserts::RedoImpl(::sw::UndoRedoContext & rContext)
         sal_uLong const nMvNd = m_pUndoNodeIndex->GetIndex();
         m_pUndoNodeIndex.reset();
         MoveFromUndoNds(*pDoc, nMvNd, *rPam.GetMark());
-        if( m_bStartWasTextNode )
+        if (m_nDeleteTextNodes != 0)
+        {
             MovePtForward(rPam, bMvBkwrd);
+        }
         rPam.Exchange();
 
         // at-char anchors post SplitNode are on index 0 of 2nd node and will