{"record":{"id":"eb9c1292c47512cc","repo":"kubernetes/kops","slug":"buildflagslist-to-reflect-value-s-eb9c12","errorCode":null,"errorMessage":"BuildFlagsList to reflect value: %s","messagePattern":"BuildFlagsList to reflect value: (.+?)","errorType":"exception","errorClass":null,"httpStatus":null,"severity":"error","filePath":"pkg/flagbuilder/build_flags.go","lineNumber":213,"sourceCode":"\t\tcase resource.Quantity:\n\t\t\t// Format as a floating point value (i.e. 3.14, not 3140m)\n\t\t\tvString := v.AsDec().String()\n\t\t\tif vString != flagEmpty {\n\t\t\t\tflag = fmt.Sprintf(\"--%s=%s\", flagName, vString)\n\t\t\t}\n\n\t\tdefault:\n\t\t\treturn fmt.Errorf(\"BuildFlagsList of value type not handled: %T %s=%v\", v, path, v)\n\t\t}\n\t\tif flag != \"\" {\n\t\t\tflags = append(flags, flag)\n\t\t}\n\n\t\treturn reflectutils.SkipReflection\n\t}\n\terr := reflectutils.ReflectRecursive(reflect.ValueOf(options), walker, &reflectutils.ReflectOptions{DeprecatedDoubleVisit: true})\n\tif err != nil {\n\t\treturn nil, fmt.Errorf(\"BuildFlagsList to reflect value: %s\", err)\n\t}\n\t// Sort so that the order is stable across runs\n\tsort.Strings(flags)\n\n\treturn flags, nil\n}\n\n// maybeQuote quotes s when it contains a double quote, so values survive the space-separated\n// string form that a shell or systemd may parse. argv values use neverQuote instead.\nfunc maybeQuote(s string) string {\n\tif strings.Contains(s, \"\\\"\") {\n\t\treturn fmt.Sprintf(\"%q\", s)\n\t}\n\treturn s\n}\n\n// neverQuote returns s unchanged, for values used directly as exec argv.\nfunc neverQuote(s string) string {","sourceCodeStart":195,"sourceCodeEnd":231,"githubUrl":"https://github.com/kubernetes/kops/blob/4c8573c808a73d578c5eadc86d410646ea0b0d73/pkg/flagbuilder/build_flags.go#L195-L231","documentation":"BuildFlagsList walks the options struct recursively using reflectutils.ReflectRecursive. Any error returned by the walker (unparseable flag spec, unhandled value type, reflection failures) is wrapped here as 'BuildFlagsList to reflect value: ...'. The original cause is embedded in the message.","triggerScenarios":"Any underlying walker error (errors 1110-1113, or an internal reflectutils failure) while reflecting the options object passed to BuildFlags/BuildFlagsList.","commonSituations":"Debugging a wrapped error and seeing only this prefix; it typically appears when a newly added config field has an unsupported type or malformed tag.","solutions":["Read the inner error after the prefix to identify the offending field/path","Fix the underlying tag or type issue reported by the wrapped error","Check the field at the path shown in the wrapped message against supported flag types"],"exampleFix":null,"handlingStrategy":"try-catch","validationCode":"// Pre-validate options struct tags/types before reflection to surface root causes early\nif err := validateFlagTags(opts); err != nil {\n\treturn fmt.Errorf(\"options invalid before BuildFlagsList: %w\", err)\n}","typeGuard":null,"tryCatchPattern":"flags, err := flagbuilder.BuildFlagsList(opts)\nif err != nil {\n\tvar inner error\n\tif strings.HasPrefix(err.Error(), \"BuildFlagsList to reflect value:\") {\n\t\tinner = fmt.Errorf(\"%s\", strings.TrimPrefix(err.Error(), \"BuildFlagsList to reflect value: \"))\n\t\treturn fmt.Errorf(\"flagbuilder walker failed: %w\", inner)\n\t}\n\treturn err\n}","preventionTips":["Read past the wrapper prefix to diagnose the root walker error","Fix tag/type issues at their source rather than handling the wrapper","Keep option structs limited to flagbuilder-supported types"],"tags":["reflection","flagbuilder","error-wrapping"],"backgroundTag":"unsupported-flag-value-type","analyzedSha":"4c8573c808a73d578c5eadc86d410646ea0b0d73","analyzedAt":"2026-09-05T04:13:19.212Z","contentChangedAt":"2026-09-05T04:13:19.212Z","schemaVersion":2},"datasetVersion":"2026-09-12T07:17:12.445Z"}