From 5d6757c5943505c6ff22262e217b1e71c1e71147 Mon Sep 17 00:00:00 2001
From: nanobowers <nanobowers@gmail.com>
Date: Tue, 10 Dec 2024 16:19:29 -0500
Subject: [PATCH] Allow constants to start with non-ascii uppercase and
 titlecase (#15148)

---
 spec/compiler/lexer/lexer_spec.cr    | 2 ++
 src/compiler/crystal/syntax/lexer.cr | 2 +-
 2 files changed, 3 insertions(+), 1 deletion(-)

diff --git a/spec/compiler/lexer/lexer_spec.cr b/spec/compiler/lexer/lexer_spec.cr
index 6813c1fe8df3..cae4959ed636 100644
--- a/spec/compiler/lexer/lexer_spec.cr
+++ b/spec/compiler/lexer/lexer_spec.cr
@@ -276,6 +276,8 @@ describe "Lexer" do
   it_lexes "&+@foo", :OP_AMP_PLUS
   it_lexes "&-@foo", :OP_AMP_MINUS
   it_lexes_const "Foo"
+  it_lexes_const "ÁrvíztűrőTükörfúrógép"
+  it_lexes_const "DžLjNjDzᾈᾉᾊ"
   it_lexes_instance_var "@foo"
   it_lexes_class_var "@@foo"
   it_lexes_globals ["$foo", "$FOO", "$_foo", "$foo123"]
diff --git a/src/compiler/crystal/syntax/lexer.cr b/src/compiler/crystal/syntax/lexer.cr
index dbca2448585d..660bcf2f6848 100644
--- a/src/compiler/crystal/syntax/lexer.cr
+++ b/src/compiler/crystal/syntax/lexer.cr
@@ -1048,7 +1048,7 @@ module Crystal
 
         scan_ident(start)
       else
-        if current_char.ascii_uppercase?
+        if current_char.uppercase? || current_char.titlecase?
           while ident_part?(next_char)
             # Nothing to do
           end