Make ryu a single header file and move it in vendor directory

Author: byroot

CHANGES.md

@@ -2,6 +2,8 @@
 
 ### Unreleased
 
+* Optimized floating point number parsing by integrating the ryu algorithm.
+
 ### 2025-10-25 (2.15.2)
 
 * Fix `JSON::Coder` to have one dedicated depth counter per invocation.

LEGAL

@@ -7,9 +7,14 @@ All the files in this distribution are covered under either the Ruby's
 license (see the file COPYING) or public-domain except some files
 mentioned below.
 
-ext/json/ext/parser/ryu_json.h::
-ext/json/ext/parser/ryu_table.h::
-  These files are adapted from the Ryu algorithm by Ulf Adams.
-  They are dual-licensed under Apache License 2.0 OR Boost Software License 1.0.
-  See ext/json/ext/parser/LICENSE-Apache2 and ext/json/ext/parser/LICENSE-Boost
-  for the full license texts.
+ext/json/ext/vendor/fpconv.h::
+  This files is adapted from https://github.com/night-shift/fpconv
+  It is licensed under Boost Software License 1.0.
+
+ext/json/ext/vendor/jeaiii-ltoa.h::
+  This files is adapted from https://github.com/jeaiii/itoa
+  It is licensed under the MIT License
+
+ext/json/ext/vendor/ryu.h::
+  This file is adapted from the Ryu algorithm by Ulf Adams https://github.com/ulfjack/ryu.
+  It is dual-licensed under Apache License 2.0 OR Boost Software License 1.0.

benchmark/parser.rb

@@ -57,8 +57,4 @@ def benchmark_parsing(name, json_output)
 benchmark_parsing "activitypub.json", File.read("#{__dir__}/data/activitypub.json")
 benchmark_parsing "twitter.json", File.read("#{__dir__}/data/twitter.json")
 benchmark_parsing "citm_catalog.json", File.read("#{__dir__}/data/citm_catalog.json")
-
-# We now vendor Ryu (https://github.com/ulfjack/ryu), a state-of-the-art float parser
-# implemented in pure C. This gives us the same performance as rapidjson's C++ float parser,
-# achieving within-error-margin parity on float-heavy workloads like canada.json.
 benchmark_parsing "float parsing", File.read("#{__dir__}/data/canada.json")

ext/json/ext/parser/LICENSE-Apache2

@@ -2,7 +2,7 @@
 #include "ruby/encoding.h"
 
 // Minimal vendored Ryu float parser optimized for JSON parsing
-#include "ryu_json.h"
+#include "../vendor/ryu.h"
 
 /* shims */
 /* This is the fallback definition from Ruby 3.4 */