tdf#118058 sw, sections in tables: no split for multiple columns

The original use-case was "group a few paragraphs together" for the
split sections inside tables, i.e. it's safe to not split when the
section has multiple columns.

And the multiple columns case would mean that we don't find where to put
the follow section inside a table, resulting in a layout loop.

Change-Id: Ifab220e582439d2e757b5645f3167b55a051a379
Reviewed-on: https://gerrit.libreoffice.org/58951
Tested-by: Jenkins
Reviewed-by: Miklos Vajna <vmiklos@collabora.co.uk>

sw/qa/extras/layout/data/tdf118058.fodt

+<?xml version="1.0" encoding="UTF-8"?>
+<office:document xmlns:office="urn:oasis:names:tc:opendocument:xmlns:office:1.0" xmlns:style="urn:oasis:names:tc:opendocument:xmlns:style:1.0" xmlns:text="urn:oasis:names:tc:opendocument:xmlns:text:1.0" xmlns:table="urn:oasis:names:tc:opendocument:xmlns:table:1.0" xmlns:draw="urn:oasis:names:tc:opendocument:xmlns:drawing:1.0" xmlns:fo="urn:oasis:names:tc:opendocument:xmlns:xsl-fo-compatible:1.0" xmlns:svg="urn:oasis:names:tc:opendocument:xmlns:svg-compatible:1.0" office:version="1.2" office:mimetype="application/vnd.oasis.opendocument.text">
+  <office:styles>
+    <style:default-style style:family="paragraph">
+      <style:paragraph-properties fo:orphans="2" fo:widows="2" fo:hyphenation-ladder-count="no-limit" style:text-autospace="ideograph-alpha" style:punctuation-wrap="hanging"/>
+    </style:default-style>
+  </office:styles>
+  <office:automatic-styles>
+    <style:style style:name="Checklist" style:family="table">
+      <style:table-properties style:width="12.338cm" table:align="margins"/>
+    </style:style>
+    <style:style style:name="Checklist.A" style:family="table-column">
+      <style:table-column-properties style:column-width="12.338cm" style:rel-column-width="65535*"/>
+    </style:style>
+    <style:style style:name="Checklist.1" style:family="table-row">
+      <style:table-row-properties fo:background-color="#ffff00">
+        <style:background-image/>
+      </style:table-row-properties>
+    </style:style>
+    <style:style style:name="Checklist.A1" style:family="table-cell">
+      <style:table-cell-properties fo:padding-left="0.25cm" fo:padding-right="0.101cm" fo:padding-top="0.101cm" fo:padding-bottom="0.101cm" fo:border="0.05pt solid #000000"/>
+    </style:style>
+    <style:style style:name="Sect1" style:family="section">
+      <style:section-properties text:dont-balance-text-columns="false" style:editable="false">
+        <style:columns fo:column-count="2" fo:column-gap="0.497cm">
+          <style:column style:rel-width="32767*" fo:start-indent="0cm" fo:end-indent="0.249cm"/>
+          <style:column style:rel-width="32768*" fo:start-indent="0.249cm" fo:end-indent="0cm"/>
+        </style:columns>
+      </style:section-properties>
+    </style:style>
+  </office:automatic-styles>
+  <office:body>
+    <office:text text:use-soft-page-breaks="true">
+      <text:p text:style-name="P5"><draw:frame draw:style-name="fr1" draw:name="Rámec2" text:anchor-type="paragraph" svg:x="-0.039cm" svg:y="1.914cm" svg:width="12.338cm" svg:height="15.399cm" draw:z-index="0"><draw:text-box><table:table table:name="Checklist" table:style-name="Checklist"><table:table-column table:style-name="Checklist.A"/><table:table-row table:style-name="Checklist.1"><table:table-cell table:style-name="Checklist.A1" office:value-type="string"><text:p text:style-name="Table_20_header"/></table:table-cell></table:table-row><table:table-row table:style-name="Checklist.1"><table:table-cell table:style-name="Checklist.A1" office:value-type="string"><text:p text:style-name="P3"/></table:table-cell></table:table-row><table:table-row table:style-name="Checklist.1"><table:table-cell table:style-name="Checklist.A1" office:value-type="string"><text:p text:style-name="Table_20_header"/></table:table-cell></table:table-row><table:table-row><table:table-cell table:style-name="Checklist.A1" office:value-type="string"><text:section text:style-name="Sect1" text:name="Oblasť1"><text:p text:style-name="P4">Para 1.</text:p><text:p text:style-name="P2">No. However, you will not be able to see the colours produced on a black-and-white set.</text:p></text:section></table:table-cell></table:table-row></table:table><text:p text:style-name="P1"/></draw:text-box></draw:frame></text:p>
+    </office:text>
+  </office:body>
+</office:document>

sw/qa/extras/layout/layout.cxx

@@ -34,6 +34,7 @@ public:
     void testUserFieldTypeLanguage();
     void testTdf109137();
     void testForcepoint72();
+    void testTdf118058();
 
     CPPUNIT_TEST_SUITE(SwLayoutWriter);
     CPPUNIT_TEST(testTdf116830);
@@ -50,6 +51,7 @@ public:
     CPPUNIT_TEST(testUserFieldTypeLanguage);
     CPPUNIT_TEST(testTdf109137);
     CPPUNIT_TEST(testForcepoint72);
+    CPPUNIT_TEST(testTdf118058);
     CPPUNIT_TEST_SUITE_END();
 
 private:
@@ -299,6 +301,13 @@ void SwLayoutWriter::testTdf109137()
 //just care it doesn't crash
 void SwLayoutWriter::testForcepoint72() { createDoc("forcepoint72-1.rtf"); }
 
+void SwLayoutWriter::testTdf118058()
+{
+    SwDoc* pDoc = createDoc("tdf118058.fodt");
+    // This resulted in a layout loop.
+    pDoc->getIDocumentLayoutAccess().GetCurrentViewShell()->CalcLayout();
+}
+
 CPPUNIT_TEST_SUITE_REGISTRATION(SwLayoutWriter);
 CPPUNIT_PLUGIN_IMPLEMENT();
 

sw/source/core/layout/sectfrm.cxx

@@ -621,7 +621,21 @@ namespace
             return true;
 
         // The frame is in a table, see if the table is in a section.
-        return !pFrame->FindTabFrame()->IsInSct();
+        bool bRet = !pFrame->FindTabFrame()->IsInSct();
+
+        if (bRet)
+        {
+            // Don't try to split if the frame itself is a section frame with
+            // multiple columns.
+            if (pFrame->IsSctFrame())
+            {
+                const SwFrame* pLower = pFrame->GetLower();
+                if (pLower && pLower->IsColumnFrame())
+                    bRet = false;
+            }
+        }
+
+        return bRet;
     }
 }