tdf#150769 sw floattable: fix lost PageDescName if section starts with a table

The bugdoc has 2 tables in it, separated by a section break (next page).
This page break was missing in Writer, so the tables overlapped.

The page break was lost because the 2nd section started with a table,
where we insert a dummy initial paragraph (to side-step the problem that
you can't have a selection starting in a table and finishing outside
that table), and once it's disposed, its properties are lost.

Fix the problem by copying the PageDescName property from the dummy
paragraph to the next paragraph before dispose. Note that we need this
combination of creating a range (using gotoNextParagraph()) and then
enumerate over the range, because gotoNextParagraph() would skip a
leading non-floating table, which would lead to an additional, not
wanted page break, as pointed out by CppunitTest_sw_ooxmlexport15's
testTdf134649_pageBreak.

This went wrong in ce5f82dbaf1c22f45a08c60eb213bc9bc821c1d1 (DOCX
import: floating table with negative top margin has to be a fly frame,
2022-01-21), and it turns out to be related to normal floating tables,
unrelated to multi-page floating tables.

Change-Id: I83245c78c63ec8f3d6015ce3e72ab232220a9fdb
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/152411
Reviewed-by: Miklos Vajna <vmiklos@collabora.com>
Tested-by: Jenkins

1 files changed, 75 insertions, 0 deletions

diff --git a/writerfilter/source/dmapper/DomainMapper_Impl.cxx b/writerfilter/source/dmapper/DomainMapper_Impl.cxx
index 1eb5753110c8..b4405517eab0 100644
--- a/writerfilter/source/dmapper/DomainMapper_Impl.cxx
+++ b/writerfilter/source/dmapper/DomainMapper_Impl.cxx
@@ -576,6 +576,79 @@ void DomainMapper_Impl::SetDocumentSettingsProperty( const OUString& rPropName,
         }
     }
 }
+
+namespace
+{
+void CopyPageDescNameToNextParagraph(const uno::Reference<lang::XComponent>& xParagraph,
+                                     const uno::Reference<text::XTextCursor>& xCursor)
+{
+    // First check if xParagraph has a non-empty page style name to copy from.
+    uno::Reference<beans::XPropertySet> xParagraphProps(xParagraph, uno::UNO_QUERY);
+    if (!xParagraphProps.is())
+    {
+        return;
+    }
+
+    uno::Any aPageDescName = xParagraphProps->getPropertyValue("PageDescName");
+    OUString sPageDescName;
+    aPageDescName >>= sPageDescName;
+    if (sPageDescName.isEmpty())
+    {
+        return;
+    }
+
+    // If so, search for the next paragraph.
+    uno::Reference<text::XParagraphCursor> xParaCursor(xCursor, uno::UNO_QUERY);
+    if (!xParaCursor.is())
+    {
+        return;
+    }
+
+    // Create a range till the next paragraph and then enumerate on the range.
+    if (!xParaCursor->gotoNextParagraph(/*bExpand=*/true))
+    {
+        return;
+    }
+
+    uno::Reference<container::XEnumerationAccess> xEnumerationAccess(xParaCursor, uno::UNO_QUERY);
+    if (!xEnumerationAccess.is())
+    {
+        return;
+    }
+
+    uno::Reference<container::XEnumeration> xEnumeration = xEnumerationAccess->createEnumeration();
+    if (!xEnumeration.is())
+    {
+        return;
+    }
+
+    xEnumeration->nextElement();
+    if (!xEnumeration->hasMoreElements())
+    {
+        return;
+    }
+
+    // We found a next item in the enumeration: it's usually a paragraph, but may be a table as
+    // well.
+    uno::Reference<beans::XPropertySet> xNextParagraph(xEnumeration->nextElement(), uno::UNO_QUERY);
+    if (!xNextParagraph.is())
+    {
+        return;
+    }
+
+    // See if there is page style set already: if so, don't touch it.
+    OUString sNextPageDescName;
+    xNextParagraph->getPropertyValue("PageDescName") >>= sNextPageDescName;
+    if (!sNextPageDescName.isEmpty())
+    {
+        return;
+    }
+
+    // Finally copy it over, so it's not lost.
+    xNextParagraph->setPropertyValue("PageDescName", aPageDescName);
+}
+}
+
 void DomainMapper_Impl::RemoveDummyParaForTableInSection()
 {
     SetIsDummyParaAddedForTableInSection(false);
@@ -603,6 +676,8 @@ void DomainMapper_Impl::RemoveDummyParaForTableInSection()
     {
         uno::Reference<container::XEnumeration> xEnumeration = xEnumerationAccess->createEnumeration();
         uno::Reference<lang::XComponent> xParagraph(xEnumeration->nextElement(), uno::UNO_QUERY);
+        // Make sure no page breaks are lost.
+        CopyPageDescNameToNextParagraph(xParagraph, xCursor);
         xParagraph->dispose();
     }
 }