From b4417ff66511ef94a80a3b49ba184603b8e85a1b Mon Sep 17 00:00:00 2001
From: Nobuyoshi Nakada <nobu@ruby-lang.org>
Date: Wed, 23 Apr 2025 11:22:55 +0900
Subject: [PATCH] Add Encoding::UNICODE_VERSION constant

---
 enc/unicode.c |  2 --
 encoding.c    | 11 +++++++++++
 inits.c       |  1 +
 3 files changed, 12 insertions(+), 2 deletions(-)

diff --git a/enc/unicode.c b/enc/unicode.c
index 18fba02476..cbfc6cdf58 100644
--- a/enc/unicode.c
+++ b/enc/unicode.c
@@ -801,7 +801,6 @@ SpecialsCopy:
   return (int )(to - to_start);
 }
 
-#if 0
 const char onigenc_unicode_version_string[] =
 #ifdef ONIG_UNICODE_VERSION_STRING
     ONIG_UNICODE_VERSION_STRING
@@ -817,4 +816,3 @@ const int onigenc_unicode_version_number[3] = {
     0
 #endif
 };
-#endif
diff --git a/encoding.c b/encoding.c
index e6b49ef145..e2aaadb5b9 100644
--- a/encoding.c
+++ b/encoding.c
@@ -1953,6 +1953,17 @@ Init_Encoding(void)
     rb_marshal_define_compat(rb_cEncoding, Qnil, 0, enc_m_loader);
 }
 
+void
+Init_unicode_version(void)
+{
+    extern const char onigenc_unicode_version_string[];
+
+    VALUE str = rb_usascii_str_new_static(onigenc_unicode_version_string,
+                                          strlen(onigenc_unicode_version_string));
+    OBJ_FREEZE(str);
+    rb_define_const(rb_cEncoding, "UNICODE_VERSION", str);
+}
+
 void
 Init_encodings(void)
 {
diff --git a/inits.c b/inits.c
index 94cec780ad..79683185df 100644
--- a/inits.c
+++ b/inits.c
@@ -75,6 +75,7 @@ rb_call_inits(void)
     CALL(ast);
     CALL(shape);
     CALL(Prism);
+    CALL(unicode_version);
 
     // enable builtin loading
     CALL(builtin);