Fix bad HTML filtering regexp for comments with extra characters

Co-authored-by: korny <[email protected]>

Author: Copilot

lib/coderay/scanners/html.rb

@@ -226,7 +226,7 @@ def scan_tokens encoder, options
             case in_tag
             when 'script', 'style'
               encoder.text_token match, :space if match = scan(/[ \t]*\n/)
-              if scan(/(\s*<!--)(?:(.*?)(-->)|(.*))/m)
+              if scan(/(\s*<!--)(?:(.*?)(-->[^\s<]*)|(.*))/m)
                 code = self[2] || self[4]
                 closing = self[3]
                 encoder.text_token self[1], :comment

test/unit/html_comment_filtering.rb

@@ -0,0 +1,49 @@
+require 'test/unit'
+require 'coderay'
+
+class HtmlCommentFilteringTest < Test::Unit::TestCase
+  
+  def test_html_comment_filtering_consistency
+    # Test case based on issue #262
+    # Comments with extra characters after --> should be handled consistently
+    
+    # Normal comment ending with -->
+    html_normal_comment = <<-HTML
+<script>
+  <!-- This is a normal comment -->
+  alert('test');
+</script>
+HTML
+    
+    # Comment ending with -->!> (extra characters after comment end)
+    html_comment_with_extra = <<-HTML
+<script>
+  <!-- This is a comment -->!>
+  alert('test');
+</script>
+HTML
+    
+    tokens_normal = CodeRay.scan(html_normal_comment, :html)
+    tokens_extra = CodeRay.scan(html_comment_with_extra, :html)
+    
+    html_normal = tokens_normal.html
+    html_extra = tokens_extra.html
+    
+    # Both comments should be properly tokenized without error tokens
+    # The normal comment should end with -->
+    assert html_normal.include?('--&gt;</span>'), "Normal comment should end with -->"
+    assert !html_normal.include?('error'), "Normal comment should not contain error tokens"
+    
+    # The comment with extra chars should end with -->!> and not have separate error tokens
+    assert html_extra.include?('--&gt;!&gt;</span>'), "Comment with extra chars should end with -->!>"
+    assert !html_extra.include?('error'), "Comment with extra chars should not contain error tokens"
+    
+    # Both should have the same basic structure: comment opening, inline content, comment closing
+    assert html_normal.include?('<span class="comment">  &lt;!--</span>'), "Normal comment should have proper opening"
+    assert html_extra.include?('<span class="comment">  &lt;!--</span>'), "Extra comment should have proper opening"
+    
+    assert html_normal.include?('<span class="inline">'), "Normal comment should have inline content"
+    assert html_extra.include?('<span class="inline">'), "Extra comment should have inline content"
+  end
+  
+end