tdf#90230 SwDoc::AppendDoc: take care of marks when inserting page break

SwDoc::AppendDoc() inserts nodes from an other document, and before
doing that, it inserts a page break at the end of the document. In case
there are marks at the end of the last paragraph, the insertion of the
page break moves them to the next page. This is a rare situation, but
happens e.g. when the source document is an empty one: then MM puts a
mark at the first paragraph of each inserted MM part, and then the first
paragraph == the last paragraph, so the mark of the only paragraph in
the document gets moved to the next page.

This is a problem on its own, but is detected by the SwIndexReg dtor
when that empty paragraph gets deleted later in SwNodes::Delete() called
by SwDoc::AppendDoc(), resulting in an assertion failure.

Triggered by commit a305a2c9 (use
bookmarks to mark mailmerge parts in a mailmerge document (fdo#80823),
2014-10-20), these not adjusted bookmarks were not detected before.

Change-Id: I89775b477a2fd3182b2bc87144aed2bfe7912aff

sw/qa/extras/mailmerge/mailmerge.cxx

@@ -406,5 +406,11 @@ DECLARE_SHELL_MAILMERGE_TEST(testTdf89214, "tdf89214.odt", "10-testing-addresses
     CPPUNIT_ASSERT(!getProperty<OUString>(xParagraph, "ListId").isEmpty());
 }
 
+DECLARE_SHELL_MAILMERGE_TEST(testTdf90230, "empty.odt", "10-testing-addresses.ods", "testing-addresses")
+{
+    // MM of an empty document caused an assertion in the SwIndexReg dtor.
+    executeMailMerge();
+}
+
 CPPUNIT_PLUGIN_IMPLEMENT();
 /* vim:set shiftwidth=4 softtabstop=4 expandtab: */

sw/source/core/doc/docnew.cxx

@@ -946,6 +946,32 @@ SwNodeIndex SwDoc::AppendDoc(const SwDoc& rSource, sal_uInt16 const nStartPageNu
         if ( pTargetPageDesc ) {
             OUString name = pTargetPageDesc->GetName();
             pTargetShell->InsertPageBreak( &name, nStartPageNumber );
+
+            // There is now a new empty text node on the new page. If it has
+            // any marks, those are from the previous page: move them back
+            // there, otherwise later we can't delete that empty text node.
+            SwNodeIndex aNodeIndex(GetNodes().GetEndOfContent(), -1);
+            if (SwTxtNode* pTxtNode = aNodeIndex.GetNode().GetTxtNode())
+            {
+                // Position of the last paragraph on the previous page.
+                --aNodeIndex;
+                SwPaM aPaM(aNodeIndex);
+                // Collect the marks starting or ending at this text node.
+                std::set<sw::mark::IMark*> aSeenMarks;
+                IDocumentMarkAccess* pMarkAccess = getIDocumentMarkAccess();
+                for (const SwIndex* pIndex = pTxtNode->GetFirstIndex(); pIndex; pIndex = pIndex->GetNext())
+                {
+                    sw::mark::IMark* pMark = const_cast<sw::mark::IMark*>(pIndex->GetMark());
+                    if (!pMark)
+                        continue;
+                    if (aSeenMarks.find(pMark) != aSeenMarks.end())
+                        continue;
+                    aSeenMarks.insert(pMark);
+                }
+                // And move them back.
+                for (sw::mark::IMark* pMark : aSeenMarks)
+                    pMarkAccess->repositionMark(pMark, aPaM);
+            }
         }
     }
 #ifdef DBG_UTIL