Updating Number.Formatting to properly print -0

4 files changed, 22 insertions, 9 deletions

diff --git a/src/classlibnative/bcltype/grisu3.cpp b/src/classlibnative/bcltype/grisu3.cpp
index 0fc9e88928..e0138f64e8 100644
--- a/src/classlibnative/bcltype/grisu3.cpp
+++ b/src/classlibnative/bcltype/grisu3.cpp
@@ -44,7 +44,7 @@ bool Grisu3::Run(double value, int count, int* dec, int* sign, wchar_t* digits)
     // kappa: A factor used for generating digits. See step 5 of the Grisu3 procedure in the paper.
 
     // Handle sign bit.
-    if (value < 0)
+    if (_signbit(value) != 0)
     {
         value = -value;
         *sign = 1;
@@ -378,4 +378,4 @@ void Grisu3::BiggestPowerTenLessThanOrEqualTo(UINT32 number,
         *exponent = 0;
         UNREACHABLE();
     }
-}
\ No newline at end of file
+}
diff --git a/src/classlibnative/bcltype/grisu3.h b/src/classlibnative/bcltype/grisu3.h
index b3c5a40efa..7f8ec82811 100644
--- a/src/classlibnative/bcltype/grisu3.h
+++ b/src/classlibnative/bcltype/grisu3.h
@@ -12,6 +12,11 @@
 
 #include "diyfp.h"
 
+#ifdef _MSC_VER
+#define _signbit signbit
+#define _signbitf signbit
+#endif
+
 struct PowerOfTen
 {
     UINT64 significand;
diff --git a/src/classlibnative/bcltype/number.cpp b/src/classlibnative/bcltype/number.cpp
index b20044ec41..ea63122515 100644
--- a/src/classlibnative/bcltype/number.cpp
+++ b/src/classlibnative/bcltype/number.cpp
@@ -288,7 +288,7 @@ void DoubleToNumberWorker( double value, int count, int* dec, int* sign, wchar_t
     if (value == 0.0)
     {
         *dec = 0;
-        *sign = 0;
+        *sign = _signbit(value);
 
         // Instead of zeroing digits, we just make it as an empty string due to performance reason.
         *digits = 0;
diff --git a/src/classlibnative/bcltype/number.h b/src/classlibnative/bcltype/number.h
index 22c74cacdb..480e6ad6a0 100644
--- a/src/classlibnative/bcltype/number.h
+++ b/src/classlibnative/bcltype/number.h
@@ -19,13 +19,21 @@ static const double LOG10V2 = 0.30102999566398119521373889472449;
 // DRIFT_FACTOR = 1 - LOG10V2 - epsilon (a small number account for drift of floating point multiplication)
 static const double DRIFT_FACTOR = 0.69;
 
+enum NUMBER_KIND : int {
+    NUMBER_KIND_Unknown = 0,
+    NUMBER_KIND_Integer = 1,
+    NUMBER_KIND_Decimal = 2,
+    NUMBER_KIND_Double = 3
+};
+
 struct NUMBER {
-    int precision;
-    int scale;
-    int sign;
-    wchar_t digits[NUMBER_MAXDIGITS + 1];
-    wchar_t* allDigits;
-    NUMBER() : precision(0), scale(0), sign(0), allDigits(NULL) {}
+    int precision;                          //  0
+    int scale;                              //  4
+    int sign;                               //  8
+    NUMBER_KIND kind;                       // 12
+    wchar_t* allDigits;                     // 16
+    wchar_t digits[NUMBER_MAXDIGITS + 1];   // 20 or 24
+    NUMBER() : precision(0), scale(0), sign(0), kind(NUMBER_KIND_Unknown), allDigits(NULL) {}
 };
 
 class COMNumber