From 2f57f40467e09e74f8375142f228afa186e43850 Mon Sep 17 00:00:00 2001
From: tompng <tomoyapenguin@gmail.com>
Date: Mon, 20 Jan 2025 20:44:37 +0900
Subject: [PATCH] Raise parse error on invalid comments

---
 ext/json/ext/parser/parser.c  | 14 +++++++-------
 test/json/json_parser_test.rb |  5 +++++
 2 files changed, 12 insertions(+), 7 deletions(-)

diff --git a/ext/json/ext/parser/parser.c b/ext/json/ext/parser/parser.c
index 907bd047..4e28e6ef 100644
--- a/ext/json/ext/parser/parser.c
+++ b/ext/json/ext/parser/parser.c
@@ -476,7 +476,7 @@ static const bool whitespace[256] = {
     ['/'] = 1,
 };
 
-static bool
+static void
 json_eat_comments(JSON_ParserState *state)
 {
     if (state->cursor + 1 < state->end) {
@@ -496,7 +496,7 @@ json_eat_comments(JSON_ParserState *state)
                     state->cursor = memchr(state->cursor, '*', state->end - state->cursor);
                     if (!state->cursor) {
                         state->cursor = state->end;
-                        break;
+                        raise_parse_error("unexpected end of input, expected closing '*/'", state->cursor);
                     } else {
                         state->cursor++;
                         if (state->cursor < state->end && *state->cursor == '/') {
@@ -508,10 +508,12 @@ json_eat_comments(JSON_ParserState *state)
                 break;
             }
             default:
-                return false;
+                raise_parse_error("unexpected token at '%s'", state->cursor);
+                break;
         }
+    } else {
+        raise_parse_error("unexpected token at '%s'", state->cursor);
     }
-    return true;
 }
 
 static inline void
@@ -521,9 +523,7 @@ json_eat_whitespace(JSON_ParserState *state)
         if (RB_LIKELY(*state->cursor != '/')) {
             state->cursor++;
         } else {
-            if (!json_eat_comments(state)) {
-                return;
-            }
+            json_eat_comments(state);
         }
     }
 }
diff --git a/test/json/json_parser_test.rb b/test/json/json_parser_test.rb
index c5ce0232..b41c929f 100644
--- a/test/json/json_parser_test.rb
+++ b/test/json/json_parser_test.rb
@@ -398,6 +398,11 @@ def test_parse_comments
       }
     JSON
     assert_equal({ "key1" => "value1" }, parse(json))
+    assert_equal({}, parse('{} /**/'))
+    assert_raise(ParserError) { parse('{} /* comment not closed') }
+    assert_raise(ParserError) { parse('{} /*/') }
+    assert_raise(ParserError) { parse('{} /x wrong comment') }
+    assert_raise(ParserError) { parse('{} /') }
   end
 
   def test_nesting