SERVER-103783 Fix NAN string on windows. (#35628)

GitOrigin-RevId: 821440affc6eeee7dc71cc656f9b94499e0d6dd0

Author: rsteinkeX

src/mongo/bson/util/builder.h

@@ -771,7 +771,8 @@ class StringBuilderImpl {
         const int prev = _buf.len();
         const int maxSize = 32;
         char* start = _buf.grow(maxSize);
-        int z = snprintf(start, maxSize, "%.16g", x);
+        int z = std::isnan(x) ? "nan\0"_sd.copy(start, maxSize) - 1
+                              : snprintf(start, maxSize, "%.16g", x);
         MONGO_verify(z >= 0);
         MONGO_verify(z < maxSize);
         _buf.setlen(prev + z);

src/mongo/idl/idl_test.cpp

@@ -444,12 +444,7 @@ TEST(IDLOneTypeTests, TestBase64StringNegative) {
 }
 
 
-// BSONElement::exactNumberLong() provides different errors on windows
-#ifdef _WIN32
-constexpr auto kNANRepr = "-nan(ind)"_sd;
-#else
 constexpr auto kNANRepr = "nan"_sd;
-#endif
 
 TEST(IDLStructTests, DurationParse) {
     IDLParserContext ctxt("duration");