tdf#100834: svl_qa_cppunit: Add unittest

Change-Id: I14896935a4735d3719b385e8e7b70094e3d68904
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/116067
Tested-by: Jenkins
Reviewed-by: Xisco Fauli <xiscofauli@libreoffice.org>
diff --git a/svl/qa/unit/svl.cxx b/svl/qa/unit/svl.cxx
index f7a39d7..745e012 100644
--- a/svl/qa/unit/svl.cxx
+++ b/svl/qa/unit/svl.cxx
@@ -1342,6 +1342,11 @@ void Test::testUserDefinedNumberFormats()
        sExpected = "003 016/113";
        checkPreviewString(aFormatter, sCode, M_PI, eLang, sExpected);
    }
    {  // tdf#100834
        sCode = "#\" string \"?/???";
        sExpected = "3 string 16/113";
        checkPreviewString(aFormatter, sCode, M_PI, eLang, sExpected);
    }
    {  // tdf#129878
        sCode =     "[HH]";
        sExpected = "#FMT";