Increased snbt float precision

Some values did not decode back to themselves. Hopefully this will fix that.

src/amulet_nbt/_nbt_encoding/_string/_cpp/write_snbt.hpp

@@ -9,6 +9,7 @@
 #include <locale>
 #include <sstream>
 #include <iomanip>
+#include <stdexcept>
 
 #include "../../../_string_encoding/_cpp/utf8.hpp"
 #include "../../../_tag/_cpp/nbt.hpp"
@@ -103,13 +104,13 @@ void write_long_snbt(std::string& snbt, const CLongTag& tag){
 template<typename T>
 inline std::string encode_float(const T& num){
     std::ostringstream oss;
-    oss << std::setprecision(std::numeric_limits<T>::digits10 + 1) << std::noshowpoint << num;
+    oss << std::setprecision(std::numeric_limits<T>::max_digits10) << std::noshowpoint << num;
     return oss.str();
 }
 
 void write_float_snbt(std::string& snbt, const CFloatTag& tag){
     if (std::isfinite(tag)){
-        snbt.append(encode_float(tag));
+        snbt.append(encode_float<CFloatTag>(tag));
         snbt.push_back('f');
     } else if (tag == std::numeric_limits<CFloatTag>::infinity()){
         snbt.append("Infinityf");
@@ -122,7 +123,7 @@ void write_float_snbt(std::string& snbt, const CFloatTag& tag){
 
 void write_double_snbt(std::string& snbt, const CDoubleTag& tag){
     if (std::isfinite(tag)){
-        snbt.append(encode_float(tag));
+        snbt.append(encode_float<CDoubleTag>(tag));
         snbt.push_back('d');
     } else if (tag == std::numeric_limits<CDoubleTag>::infinity()){
         snbt.append("Infinityd");
@@ -298,7 +299,7 @@ std::vector<std::pair<std::string, TagNode>> sort_compound(const CCompoundTagPtr
     std::locale locale;
     try {
         locale = std::locale("en_US.UTF-8");
-    } catch (const std::runtime_error& error) {
+    } catch (const std::runtime_error&) {
         locale = std::locale("");
     }
     std::sort(keys.begin(), keys.end(), [&locale](

tests/test_amulet_nbt/test_tag/test_float.py

@@ -23,32 +23,32 @@
 
 ToSNBTData: list[tuple[float, str, str]] = [
     (float("-inf"), "-Infinityf", "-Infinityd"),
-    (-9999999999999999, "-1e+16f", "-1e+16d"),
-    (-99999999, "-1e+08f", "-99999999d"),
+    (-9999999999999999, "-1.00000003e+16f", "-10000000000000000d"),
+    (-99999999, "-100000000f", "-99999999d"),
     (-9999, "-9999f", "-9999d"),
     (-99, "-99f", "-99d"),
     (-9, "-9f", "-9d"),
     (-1, "-1f", "-1d"),
-    (-0.1, "-0.1f", "-0.1d"),
-    (-0.01, "-0.01f", "-0.01d"),
-    (-0.001, "-0.001f", "-0.001d"),
-    (-0.00001, "-1e-05f", "-1e-05d"),
-    (-0.000000001, "-1e-09f", "-1e-09d"),
-    (-0.00000000000000001, "-1e-17f", "-1e-17d"),
+    (-0.1, "-0.100000001f", "-0.10000000000000001d"),
+    (-0.01, "-0.00999999978f", "-0.01d"),
+    (-0.001, "-0.00100000005f", "-0.001d"),
+    (-0.00001, "-9.99999975e-06f", "-1.0000000000000001e-05d"),
+    (-0.000000001, "-9.99999972e-10f", "-1.0000000000000001e-09d"),
+    (-0.00000000000000001, "-9.99999984e-18f", "-1.0000000000000001e-17d"),
     (float("-0"), "-0f", "-0d"),
     (float("+0"), "0f", "0d"),
-    (0.00000000000000001, "1e-17f", "1e-17d"),
-    (0.000000001, "1e-09f", "1e-09d"),
-    (0.00001, "1e-05f", "1e-05d"),
-    (0.001, "0.001f", "0.001d"),
-    (0.01, "0.01f", "0.01d"),
-    (0.1, "0.1f", "0.1d"),
+    (0.00000000000000001, "9.99999984e-18f", "1.0000000000000001e-17d"),
+    (0.000000001, "9.99999972e-10f", "1.0000000000000001e-09d"),
+    (0.00001, "9.99999975e-06f", "1.0000000000000001e-05d"),
+    (0.001, "0.00100000005f", "0.001d"),
+    (0.01, "0.00999999978f", "0.01d"),
+    (0.1, "0.100000001f", "0.10000000000000001d"),
     (1, "1f", "1d"),
     (9, "9f", "9d"),
     (99, "99f", "99d"),
     (9999, "9999f", "9999d"),
-    (99999999, "1e+08f", "99999999d"),
-    (9999999999999999, "1e+16f", "1e+16d"),
+    (99999999, "100000000f", "99999999d"),
+    (9999999999999999, "1.00000003e+16f", "10000000000000000d"),
     (float("inf"), "Infinityf", "Infinityd"),
     (
         struct.unpack(">d", b"\x7f\xf0\x00\x00\x00\x00\x00\x01")[0],