sw XHTML export: avoid writing default transparent background for ReqIF

We started writing properties of tables and rows since commit
c3c3303516c3da9372dce3f05f38f15a104e961c (sw XHTML export: output table
/ table row background format using CSS, 2022-05-10).

In case the SwTableLine has an explicit SvxBrushItem with its color set
to COL_TRANSPARENT, we turn that into a "background: transparent" CSS by
default. This is a 1:1 mapping from the doc model, but HTML defaults to
this already, so this is considered as noise.

Extend IgnorePropertyForReqIF() to filter out these unwanted defaults,
and fix SwHTMLWriter::OutCSS1_Property(), because it used to not pass
the CSS value for the filter function.

The behavior for table cells is unchanged, we continue to not export
cell properties (in the ReqIF case) at all.

Change-Id: Idbcd07809e159def694f4de017eebc7ad4104575
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/135576
Tested-by: Jenkins
Reviewed-by: Miklos Vajna <vmiklos@collabora.com>
(cherry picked from commit 04cc6e079e3122c183054fde046c054ed6c7b737)
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/135707
Reviewed-by: Michael Stahl <michael.stahl@allotropia.de>

2 files changed, 26 insertions, 3 deletions

diff --git a/sw/qa/extras/htmlexport/htmlexport.cxx b/sw/qa/extras/htmlexport/htmlexport.cxx
index 68175f6d077c..f95f08d4c6de 100644
--- a/sw/qa/extras/htmlexport/htmlexport.cxx
+++ b/sw/qa/extras/htmlexport/htmlexport.cxx
@@ -2134,10 +2134,14 @@ CPPUNIT_TEST_FIXTURE(SwHtmlDomExportTest, testTableBackground)
     pWrtShell->SetTabBackground(aBrush);
     pWrtShell->Down(/*bSelect=*/false);
     pWrtShell->SplitNode();
-    pWrtShell->InsertTable(aInsertTableOptions, /*nRows=*/1, /*nCols=*/1);
+    pWrtShell->InsertTable(aInsertTableOptions, /*nRows=*/2, /*nCols=*/1);
     pWrtShell->MoveTable(GotoPrevTable, fnTableStart);
     aBrush.SetColor(0x00ff00);
     pWrtShell->SetRowBackground(aBrush);
+    pWrtShell->Down(/*bSelect=*/false);
+    // Second row has an explicit transparent background.
+    aBrush.SetColor(COL_TRANSPARENT);
+    pWrtShell->SetRowBackground(aBrush);
 
     // When exporting to reqif-xhtml:
     ExportToReqif();
@@ -2154,6 +2158,8 @@ CPPUNIT_TEST_FIXTURE(SwHtmlDomExportTest, testTableBackground)
     assertXPath(pXmlDoc, "//reqif-xhtml:table[2]/reqif-xhtml:tr[1]", "style",
                 "background: #00ff00");
     assertXPathNoAttribute(pXmlDoc, "//reqif-xhtml:table[2]/reqif-xhtml:tr[1]", "bgcolor");
+    // Second row has no explicit style, the default is not written.
+    assertXPathNoAttribute(pXmlDoc, "//reqif-xhtml:table[2]/reqif-xhtml:tr[2]", "style");
 }
 
 CPPUNIT_TEST_FIXTURE(HtmlExportTest, testImageKeepRatio)
diff --git a/sw/source/filter/html/css1atr.cxx b/sw/source/filter/html/css1atr.cxx
index 3cb646e0f1de..b4c8ce82cf02 100644
--- a/sw/source/filter/html/css1atr.cxx
+++ b/sw/source/filter/html/css1atr.cxx
@@ -185,9 +185,21 @@ OString lclConvToHex(sal_uInt16 nHex)
 bool IgnorePropertyForReqIF(bool bReqIF, std::string_view rProperty, std::string_view rValue,
                             std::optional<sw::Css1Background> oMode)
 {
-    if (!bReqIF || (oMode.has_value() && *oMode != sw::Css1Background::TableCell))
+    if (!bReqIF)
         return false;
 
+    if (oMode.has_value() && *oMode != sw::Css1Background::TableCell)
+    {
+        // Table or row.
+        if (rProperty == sCSS1_P_background && rValue == "transparent")
+        {
+            // This is the default already.
+            return true;
+        }
+
+        return false;
+    }
+
     // Only allow these two keys, nothing else in ReqIF mode.
     if (rProperty == sCSS1_P_text_decoration)
     {
@@ -244,7 +256,12 @@ void SwHTMLWriter::OutCSS1_Property( const char *pProp,
                                      const OUString *pSVal,
                                      std::optional<sw::Css1Background> oMode )
 {
-    if (IgnorePropertyForReqIF(mbReqIF, pProp, sVal, oMode))
+    OString aPropertyValue(sVal);
+    if (aPropertyValue.isEmpty() && pSVal)
+    {
+        aPropertyValue = pSVal->toUtf8();
+    }
+    if (IgnorePropertyForReqIF(mbReqIF, pProp, aPropertyValue, oMode))
         return;
 
     OStringBuffer sOut;