Resolves: tdf#100452 class Date full (BCE,CE) proleptic Gregorian calendar

... implementing signed years with year 0 gap.
Date(31,12,-1) last day BCE
Date(1,1,1) first day CE

New class Date member functions:
* AddYears(sal_Int16) to be used instead of
aDate.SetYear(aDate.GetYear()+sal_Int16) to handle year 0 gap.
* convenience GetNextYear() to be used insted of GetYear()+1
* convenience GetPrevYear() to be used insted of GetYear()-1
* AddMonths(sal_Int32)
* operator=(const css::util::Date&)

New class DateTime member functions:
* operator=(const css::util::DateTime&)

Made some conversion ctors explicit, specifically Date(sal_Int32)

Adapted hopefully all places that used a sal_uInt16 year to use
sal_Int16 where appropriate.

Eliminated some quirks in date handling found on the fly.

Added era handling to i18npool icu calendar setting interface, which
missing was responsible for 0001-01-01 entered in Calc being set as
-0001-01-01, hence subtracting one day resulted in -0002-12-31.

Change-Id: I77b39fba9599ebd5067d7864f6c9ebe01f6f578f
Reviewed-on: https://gerrit.libreoffice.org/27049
Reviewed-by: Eike Rathke <erack@redhat.com>
Tested-by: Jenkins <ci@libreoffice.org>

5 files changed, 5 insertions, 5 deletions

diff --git a/svl/source/numbers/zforfind.cxx b/svl/source/numbers/zforfind.cxx
index 6154e2a9bb78..7fc7f8c079fd 100644
--- a/svl/source/numbers/zforfind.cxx
+++ b/svl/source/numbers/zforfind.cxx
@@ -3406,7 +3406,7 @@ void ImpSvNumberInputScan::InvalidateDateAcceptancePatterns()
 
 void ImpSvNumberInputScan::ChangeNullDate( const sal_uInt16 Day,
                                            const sal_uInt16 Month,
-                                           const sal_uInt16 Year )
+                                           const sal_Int16 Year )
 {
     if ( pNullDate )
     {
diff --git a/svl/source/numbers/zforfind.hxx b/svl/source/numbers/zforfind.hxx
index 7cabce77cf2a..5f62e281f10c 100644
--- a/svl/source/numbers/zforfind.hxx
+++ b/svl/source/numbers/zforfind.hxx
@@ -40,7 +40,7 @@ public:
     /// set reference date for offset calculation
     void ChangeNullDate( const sal_uInt16 nDay,
                          const sal_uInt16 nMonth,
-                         const sal_uInt16 nYear );
+                         const sal_Int16 nYear );
 
     /// convert input string to number
     bool IsNumberFormat( const OUString& rString,            /// input string
diff --git a/svl/source/numbers/zforlist.cxx b/svl/source/numbers/zforlist.cxx
index bd67e25e9c09..5ca78ed0b370 100644
--- a/svl/source/numbers/zforlist.cxx
+++ b/svl/source/numbers/zforlist.cxx
@@ -398,7 +398,7 @@ Color* SvNumberFormatter::GetUserDefColor(sal_uInt16 nIndex)
 
 void SvNumberFormatter::ChangeNullDate(sal_uInt16 nDay,
                                        sal_uInt16 nMonth,
-                                       sal_uInt16 nYear)
+                                       sal_Int16 nYear)
 {
     pFormatScanner->ChangeNullDate(nDay, nMonth, nYear);
     pStringScanner->ChangeNullDate(nDay, nMonth, nYear);
diff --git a/svl/source/numbers/zforscan.cxx b/svl/source/numbers/zforscan.cxx
index b208364d5e95..8025ae6fd1e0 100644
--- a/svl/source/numbers/zforscan.cxx
+++ b/svl/source/numbers/zforscan.cxx
@@ -446,7 +446,7 @@ void ImpSvNumberformatScan::SetDependentKeywords()
     InitCompatCur();
 }
 
-void ImpSvNumberformatScan::ChangeNullDate(sal_uInt16 nDay, sal_uInt16 nMonth, sal_uInt16 nYear)
+void ImpSvNumberformatScan::ChangeNullDate(sal_uInt16 nDay, sal_uInt16 nMonth, sal_Int16 nYear)
 {
     if ( pNullDate )
         *pNullDate = Date(nDay, nMonth, nYear);
diff --git a/svl/source/numbers/zforscan.hxx b/svl/source/numbers/zforscan.hxx
index 82535fd1e84a..bf92049bae1f 100644
--- a/svl/source/numbers/zforscan.hxx
+++ b/svl/source/numbers/zforscan.hxx
@@ -44,7 +44,7 @@ public:
     ~ImpSvNumberformatScan();
     void ChangeIntl(); // Replaces Keywords
 
-    void ChangeNullDate(sal_uInt16 nDay, sal_uInt16 nMonth, sal_uInt16 nYear); // Replaces reference date
+    void ChangeNullDate(sal_uInt16 nDay, sal_uInt16 nMonth, sal_Int16 nYear); // Replaces reference date
     void ChangeStandardPrec(sal_uInt16 nPrec); // Replaces standard precision
 
     sal_Int32 ScanFormat( OUString& rString ); // Call scan analysis