sw: DOCX export: export AddExternalLeading as w:noLeading

For 11pt Arial, can fit 59 paragraphs on a page vs. 57...

This is annoyingly complicated by the fact that Word 2013 ignores
w:noLeading element if compatibilityMode is 15.

Change-Id: Ie3093eabba45cdf6e7903ed860f5bad24dcc0323
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/92208
Tested-by: Jenkins
Reviewed-by: Michael Stahl <michael.stahl@cib.de>

3 files changed, 37 insertions, 11 deletions

diff --git a/sw/qa/extras/ooxmlexport/ooxmlexport5.cxx b/sw/qa/extras/ooxmlexport/ooxmlexport5.cxx
index 95fcebbf9c42..ee4b35698533 100644
--- a/sw/qa/extras/ooxmlexport/ooxmlexport5.cxx
+++ b/sw/qa/extras/ooxmlexport/ooxmlexport5.cxx
@@ -1119,10 +1119,11 @@ DECLARE_OOXMLEXPORT_TEST(tdf106843, "tdf106843.fodt")
         assertXPath(pXmlSettings, "/w:settings/w:documentProtection", "edit",               "trackedChanges");
         assertXPath(pXmlSettings, "/w:settings/w:documentProtection", "enforcement",        "1");
 
-        // LO intends to export a .docx format that is natively compatible with 2013.
+        // LO intends to export a .docx format that is natively compatible with 2013
+        // but this document has an implicitly added setting AddExternalLeading = false
         assertXPath(pXmlSettings, "/w:settings/w:compat/w:compatSetting[1]", "name", "compatibilityMode");
         assertXPath(pXmlSettings, "/w:settings/w:compat/w:compatSetting[1]", "uri", "http://schemas.microsoft.com/office/word");
-        assertXPath(pXmlSettings, "/w:settings/w:compat/w:compatSetting[1]", "val", "15"); // compatible with 2003/2016/2019
+        assertXPath(pXmlSettings, "/w:settings/w:compat/w:compatSetting[1]", "val", "14"); // compatible with 2010
     }
 }
 
diff --git a/sw/source/filter/ww8/docxattributeoutput.cxx b/sw/source/filter/ww8/docxattributeoutput.cxx
index a8ed8e88a47d..10afeb9fd918 100644
--- a/sw/source/filter/ww8/docxattributeoutput.cxx
+++ b/sw/source/filter/ww8/docxattributeoutput.cxx
@@ -3770,6 +3770,15 @@ sal_Int32 lcl_getWordCompatibilityMode( const SwDoc& rDoc )
         }
     }
 
+    // TODO: this is duplicative, better store it in DocxExport member?
+    if (!rDoc.getIDocumentSettingAccess().get(DocumentSettingId::ADD_EXT_LEADING))
+    {
+        if (nWordCompatibilityMode == -1 || 14 < nWordCompatibilityMode)
+        {
+            nWordCompatibilityMode = 14;
+        }
+    }
+
     return nWordCompatibilityMode;
 }
 
diff --git a/sw/source/filter/ww8/docxexport.cxx b/sw/source/filter/ww8/docxexport.cxx
index 035f50cbeaac..b18d94410027 100644
--- a/sw/source/filter/ww8/docxexport.cxx
+++ b/sw/source/filter/ww8/docxexport.cxx
@@ -944,6 +944,25 @@ void DocxExport::WriteDocVars(const sax_fastparser::FSHelperPtr& pFS)
     }
 }
 
+static auto
+WriteCompat(SwDoc const& rDoc, ::sax_fastparser::FSHelperPtr const& rpFS,
+        sal_Int32 & rTargetCompatibilityMode) -> void
+{
+    if (!rDoc.getIDocumentSettingAccess().get(DocumentSettingId::ADD_EXT_LEADING))
+    {
+        rpFS->singleElementNS(XML_w, XML_noLeading);
+        if (rTargetCompatibilityMode > 14)
+        {   // Word ignores noLeading in compatibilityMode 15
+            rTargetCompatibilityMode = 14;
+        }
+    }
+    // Do not justify lines with manual break
+    if (rDoc.getIDocumentSettingAccess().get(DocumentSettingId::DO_NOT_JUSTIFY_LINES_WITH_MANUAL_BREAK))
+    {
+        rpFS->singleElementNS(XML_w, XML_doNotExpandShiftReturn);
+    }
+}
+
 void DocxExport::WriteSettings()
 {
     SwViewShell *pViewShell(m_pDoc->getIDocumentLayoutAccess().GetCurrentViewShell());
@@ -1027,14 +1046,6 @@ void DocxExport::WriteSettings()
         pFS->singleElementNS( XML_w, XML_defaultTabStop, FSNS( XML_w, XML_val ),
             OString::number(m_aSettings.defaultTabStop) );
 
-    // Do not justify lines with manual break
-    if( m_pDoc->getIDocumentSettingAccess().get( DocumentSettingId::DO_NOT_JUSTIFY_LINES_WITH_MANUAL_BREAK ))
-    {
-        pFS->startElementNS(XML_w, XML_compat);
-        pFS->singleElementNS(XML_w, XML_doNotExpandShiftReturn);
-        pFS->endElementNS( XML_w, XML_compat );
-    }
-
     // export current mail merge database and table names
     SwDBData aData = m_pDoc->GetDBData();
     if ( !aData.sDataSource.isEmpty() && aData.nCommandType == css::sdb::CommandType::TABLE && !aData.sCommand.isEmpty() )
@@ -1121,7 +1132,7 @@ void DocxExport::WriteSettings()
      * 2.) Many years later, change the TargetCompatilityMode for new documents, when we no longer care
      *     about working with perfect compatibility with older versions of MS Word.
      */
-    const sal_Int32 nTargetCompatibilityMode = 15; //older versions might not open our files well
+    sal_Int32 nTargetCompatibilityMode = 15; //older versions might not open our files well
     bool bHasCompatibilityMode = false;
     const OUString aGrabBagName = UNO_NAME_MISC_OBJ_INTEROPGRABBAG;
     if ( xPropSetInfo->hasPropertyByName( aGrabBagName ) )
@@ -1154,6 +1165,8 @@ void DocxExport::WriteSettings()
             {
                 pFS->startElementNS(XML_w, XML_compat);
 
+                WriteCompat(*m_pDoc, pFS, nTargetCompatibilityMode);
+
                 uno::Sequence< beans::PropertyValue > aCompatSettingsSequence;
                 rProp.Value >>= aCompatSettingsSequence;
 
@@ -1282,6 +1295,9 @@ void DocxExport::WriteSettings()
     if ( !bHasCompatibilityMode )
     {
         pFS->startElementNS(XML_w, XML_compat);
+
+        WriteCompat(*m_pDoc, pFS, nTargetCompatibilityMode);
+
         pFS->singleElementNS( XML_w, XML_compatSetting,
             FSNS( XML_w, XML_name ), "compatibilityMode",
             FSNS( XML_w, XML_uri ),  "http://schemas.microsoft.com/office/word",