Resolves: tdf#117819 append trailing '0' as needed before separator insertion

To insert separators, literal strings between digits and other,
the formatter operates backwards on the string obtained from
doubleToUString() cleaned of the decimal separator. The number of
decimals returned by doubleToUString() may be less than the
decimals of the number format as entered by the user, which lead
to separators inserted at wrong positions. This wrong behavior was
triggered respectively made more obvious by

    commit 0f6203edf74832f84d8263d7a544d679203a4efc
    CommitDate: Wed Jan 13 14:47:57 2016 +0100

        tdf#96918 display accurate integer double values up to (2^53)-1

which for integer values returns at most 15 decimals ('0' in this
case).

Before operating on the decimals' part ensure that the number of
decimals matches the digits requested, and if shorter append
trailing '0' characters for the required amount so the separators
(and other strings) are inserted at the correct positions.

Change-Id: Ic02652699ea7d6fae3b2b3348f6f7d183319e043
Reviewed-on: https://gerrit.libreoffice.org/55039
Reviewed-by: Eike Rathke <erack@redhat.com>
Tested-by: Eike Rathke <erack@redhat.com>
(cherry picked from commit 8b43f58891d4b422a8934050d839b0c2c1e3a18a)
Reviewed-on: https://gerrit.libreoffice.org/55059
Tested-by: Jenkins <ci@libreoffice.org>

2 files changed, 26 insertions, 6 deletions

diff --git a/include/svl/zformat.hxx b/include/svl/zformat.hxx
index 38479dfc6aef..33b5bf8b2062 100644
--- a/include/svl/zformat.hxx
+++ b/include/svl/zformat.hxx
@@ -622,6 +622,7 @@ private:
 
     SVL_DLLPRIVATE bool ImpDecimalFill( OUStringBuffer& sStr,
                                  double& rNumber,
+                                 sal_Int32 nDecPos,
                                  sal_uInt16 j,
                                  sal_uInt16 nIx,
                                  bool bInteger );
diff --git a/svl/source/numbers/zformat.cxx b/svl/source/numbers/zformat.cxx
index 984c85f108f0..1a0b80e30a34 100644
--- a/svl/source/numbers/zformat.cxx
+++ b/svl/source/numbers/zformat.cxx
@@ -2525,6 +2525,7 @@ bool SvNumberformat::ImpGetScientificOutput(double fNumber,
     OUStringBuffer ExpStr;
     short nExpSign = 1;
     sal_Int32 nExPos = sStr.indexOf('E');
+    sal_Int32 nDecPos = -1;
 
     if ( nExPos >= 0 )
     {
@@ -2583,6 +2584,8 @@ bool SvNumberformat::ImpGetScientificOutput(double fNumber,
 
         while((index = sStr.indexOf('.', index)) >= 0)
         {
+            if (nDecPos < 0)
+                nDecPos = index;
             sStr.remove(index, 1);
         }
     }
@@ -2632,7 +2635,7 @@ bool SvNumberformat::ImpGetScientificOutput(double fNumber,
     }
     else
     {
-        bRes |= ImpDecimalFill(sStr, fNumber, j, nIx, false);
+        bRes |= ImpDecimalFill(sStr, fNumber, nDecPos, j, nIx, false);
     }
 
     if (bSign)
@@ -4106,6 +4109,7 @@ bool SvNumberformat::ImpGetNumberOutput(double fNumber,
         }
     }
     sal_uInt16 i, j;
+    sal_Int32 nDecPos = -1;
     bool bInteger = false;
     if ( rInfo.nThousand != FLAG_STANDARD_IN_FORMAT )
     {
@@ -4157,17 +4161,17 @@ bool SvNumberformat::ImpGetNumberOutput(double fNumber,
             sStr = ::rtl::math::doubleToUString( fNumber, rtl_math_StringFormat_F, 0, '.');
             sStr.stripStart('0'); // Strip leading zeros
         }
-        sal_Int32 nPoint = sStr.indexOf('.' );
-        if ( nPoint >= 0)
+        nDecPos = sStr.indexOf('.' );
+        if ( nDecPos >= 0)
         {
-            const sal_Unicode* p = sStr.getStr() + nPoint;
+            const sal_Unicode* p = sStr.getStr() + nDecPos;
             while ( *++p == '0' )
                 ;
             if ( !*p )
             {
                 bInteger = true;
             }
-            sStr.remove( nPoint, 1 ); //  Remove .
+            sStr.remove( nDecPos, 1 ); //  Remove .
         }
         if (bSign && (sStr.isEmpty() ||
                       comphelper::string::getTokenCount(sStr.toString(), '0') == sStr.getLength()+1))   // Only 00000
@@ -4179,7 +4183,7 @@ bool SvNumberformat::ImpGetNumberOutput(double fNumber,
                                         // Edit backwards:
     j = NumFor[nIx].GetCount()-1;       // Last symbol
                                         // Decimal places:
-    bRes |= ImpDecimalFill( sStr, fNumber, j, nIx, bInteger );
+    bRes |= ImpDecimalFill( sStr, fNumber, nDecPos, j, nIx, bInteger );
     if (bSign)
     {
         sStr.insert(0, '-');
@@ -4190,6 +4194,7 @@ bool SvNumberformat::ImpGetNumberOutput(double fNumber,
 
 bool SvNumberformat::ImpDecimalFill( OUStringBuffer& sStr,  // number string
                                    double& rNumber,       // number
+                                   sal_Int32 nDecPos,     // decimals start
                                    sal_uInt16 j,          // symbol index within format code
                                    sal_uInt16 nIx,        // subformat index
                                    bool bInteger)         // is integer
@@ -4234,6 +4239,20 @@ bool SvNumberformat::ImpDecimalFill( OUStringBuffer& sStr,  // number string
                 const OUString& rStr = rInfo.sStrArray[j];
                 const sal_Unicode* p1 = rStr.getStr();
                 const sal_Unicode* p = p1 + rStr.getLength();
+                // In case the number of decimals passed are less than the
+                // "digits" given, append trailing '0' characters, which here
+                // means insert them because literal strings may have been
+                // appended already. If they weren't to be '0' characters
+                // they'll be changed below, as if decimals with trailing zeros
+                // were passed.
+                if (nDecPos >= 0 && nDecPos <= k)
+                {
+                    sal_Int32 nAppend = rStr.getLength() - (k - nDecPos);
+                    while (nAppend-- > 0)
+                    {
+                        sStr.insert( k++, '0');
+                    }
+                }
                 while (k && p1 < p--)
                 {
                     const sal_Unicode c = *p;