1 files changed, 19 insertions, 0 deletions
diff --git a/test/prism/ruby/location_test.rb b/test/prism/ruby/location_test.rb
index fc80a5b875..e360a0db72 100644
--- a/test/prism/ruby/location_test.rb
+++ b/test/prism/ruby/location_test.rb
@@ -140,6 +140,25 @@ module Prism
       assert_equal 7, location.end_code_units_column(Encoding::UTF_32LE)
     end
 
+    def test_code_units_handles_binary_encoding_with_multibyte_characters
+      # If the encoding is set to binary and the source contains multibyte
+      # characters, we avoid breaking the code unit offsets, but they will
+      # still be incorrect.
+
+      program = Prism.parse(<<~RUBY).value
+        # -*- encoding: binary -*-
+
+        😀 + 😀
+      RUBY
+
+      # first 😀
+      location = program.statements.body.first.receiver.location
+
+      assert_equal 4, location.end_code_units_column(Encoding::UTF_8)
+      assert_equal 4, location.end_code_units_column(Encoding::UTF_16LE)
+      assert_equal 4, location.end_code_units_column(Encoding::UTF_32LE)
+    end
+
     def test_chop
       location = Prism.parse("foo").value.location