From 20f8d4549b442e0947205ccf9a88ddcd58a3bd13 Mon Sep 17 00:00:00 2001
From: Earlopain <14981592+Earlopain@users.noreply.github.com>
Date: Wed, 2 Sep 2026 11:20:42 +0200
Subject: [PATCH] Fix `Comment#trailing` for syntax invalid edgecase

When prism encounter invalid bytes and still  switches over to parsing comments,
`strip` will raise

`syntax_suggest` might run into this via `ruby/spec`
---
 lib/prism/parse_result.rb          |  2 ++
 test/prism/result/comments_test.rb | 10 ++++++++++
 2 files changed, 12 insertions(+)

diff --git a/lib/prism/parse_result.rb b/lib/prism/parse_result.rb
index 92eb56bf36..e9380d0f09 100644
--- a/lib/prism/parse_result.rb
+++ b/lib/prism/parse_result.rb
@@ -744,6 +744,8 @@ class InlineComment < Comment
     #: () -> bool
     def trailing?
       !location.start_line_slice.strip.empty?
+    rescue ArgumentError # invalid bytes, never whitespace only
+      false
     end
 
     # Returns a string representation of this comment.
diff --git a/test/prism/result/comments_test.rb b/test/prism/result/comments_test.rb
index 178623a75f..140eddd5d1 100644
--- a/test/prism/result/comments_test.rb
+++ b/test/prism/result/comments_test.rb
@@ -39,6 +39,16 @@ def foo
       )
     end
 
+    def test_comment_trailing
+      comment = Prism.parse_comments("x # trailing")[0]
+      assert_predicate(comment, :trailing?)
+    end
+
+    def test_comment_syntax_invalid_bytes_trailing
+      comment = Prism.parse_comments("\xFF\xFE# not trailing")[0]
+      refute_predicate(comment, :trailing?)
+    end
+
     def test___END__
       result = Prism.parse(<<~RUBY)
         __END__