Resolves: tdf#158265 Store more than 100th seconds precision in date+time

e.g. office:date-value

Change-Id: I9bb4b589cdb8c6f04fa39ba7ec4254207eaa3663
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/160124
Reviewed-by: Eike Rathke <erack@redhat.com>
Tested-by: Jenkins

1 files changed, 10 insertions, 1 deletions

diff --git a/xmloff/source/core/xmluconv.cxx b/xmloff/source/core/xmluconv.cxx
index a95de5ecb66c..544bea50d3c5 100644
--- a/xmloff/source/core/xmluconv.cxx
+++ b/xmloff/source/core/xmluconv.cxx
@@ -61,7 +61,6 @@ using namespace ::com::sun::star::i18n;
 using namespace ::xmloff::token;
 
 
-const sal_Int8 XML_MAXDIGITSCOUNT_TIME = 11;
 constexpr OUStringLiteral XML_NULLDATE = u"NullDate";
 
 struct SvXMLUnitConverter::Impl
@@ -444,6 +443,16 @@ void SvXMLUnitConverter::convertDateTime( OUStringBuffer& rBuffer,
     else
         fCount = 0.0;
     const int nDigits = sal_Int16(fCount) + 4;  // +4 for *86400 in seconds
+
+    // Since the beginning from initial source code import this was 11 without
+    // further explanation, effectively limiting fractions in ~current
+    // date+time to 2 decimals (maybe because old class Time code had a
+    // resolution of only 100th seconds). Preserve at least milliseconds, but
+    // strive for more.
+    // NOTE: sax/source/tools/converter.cxx uses 14-5 in a different context
+    // rounding nanoseconds and fractions of seconds.
+    constexpr int XML_MAXDIGITSCOUNT_TIME = 14;
+
     const int nFractionDecimals = std::max( XML_MAXDIGITSCOUNT_TIME - nDigits, 0);
 
     sal_uInt16 nHour, nMinute, nSecond;