{"record":{"id":"9308a4d41118c82b","repo":"ruby/rubygems","slug":"undefined-class-module-node-tag-sub-ruby-objec","errorCode":null,"errorMessage":"undefined class/module #{node.tag.sub(\"!ruby/object:\", \"\")}","messagePattern":"undefined class/module #(.+?)","errorType":"validation","errorClass":"ArgumentError","httpStatus":null,"severity":"error","filePath":"lib/rubygems/yaml_serializer.rb","lineNumber":537,"sourceCode":"        validate_tag!(node.tag) if node.tag\n\n        result = case node.tag\n                 when \"!ruby/object:Gem::Version\"\n                   build_version(node)\n                 when \"!ruby/object:Gem::Platform\"\n                   build_platform(node)\n                 when \"!ruby/object:Gem::Requirement\", \"!ruby/object:Gem::Version::Requirement\"\n                   build_requirement(node)\n                 when \"!ruby/object:Gem::Dependency\"\n                   build_dependency(node)\n                 when nil\n                   build_hash(node)\n                 when \"!ruby/object:Gem::Specification\"\n                   hash = build_hash(node)\n                   hash[:tag] = node.tag\n                   hash\n                 else\n                   raise ArgumentError, \"undefined class/module #{node.tag.sub(\"!ruby/object:\", \"\")}\"\n        end\n\n        store_anchor(node.anchor, result)\n      end\n\n      def build_hash(node)\n        result = {}\n        node.pairs.each do |key_node, value_node|\n          key = key_node.is_a?(Scalar) ? key_node.value.to_s : build_node(key_node).to_s\n          value = build_node(value_node)\n\n          if ARRAY_FIELDS.include?(key)\n            value = normalize_array_field(value)\n          end\n\n          result[key] = value\n        end\n        result","sourceCodeStart":519,"sourceCodeEnd":555,"githubUrl":"https://github.com/ruby/rubygems/blob/86cbb817a38ce8477b181c17467a703ded3f2be8/lib/rubygems/yaml_serializer.rb#L519-L555","documentation":"Error \"undefined class/module #{node.tag.sub(\"!ruby/object:\", \"\")}\" thrown in ruby/rubygems.","triggerScenarios":"Thrown at lib/rubygems/yaml_serializer.rb:537 when the library encounters an invalid state.","commonSituations":"See trigger scenarios.","solutions":["The metadata references a class/module that is not defined; rebuild the gem with a current RubyGems"],"exampleFix":null,"handlingStrategy":null,"validationCode":null,"typeGuard":null,"tryCatchPattern":null,"preventionTips":[],"tags":[],"backgroundTag":null,"analyzedSha":"86cbb817a38ce8477b181c17467a703ded3f2be8","analyzedAt":"2026-08-23T06:27:48.159Z","schemaVersion":2},"datasetVersion":"2026-08-23T08:06:27.607Z"}