{"record":{"id":"5e543a1e195b2ee7","repo":"go-task/task","slug":"task-you-can-t-set-output-group-begin-without","errorCode":null,"errorMessage":"task: You can't set --output-group-begin without --output=group","messagePattern":"task: You can't set --output-group-begin without --output=group","errorType":"validation","errorClass":null,"httpStatus":null,"severity":"error","filePath":"internal/flags/flags.go","lineNumber":218,"sourceCode":"\treturn ci\n}\n\nfunc Validate() error {\n\tif Download && Offline {\n\t\treturn errors.New(\"task: You can't set both --download and --offline flags\")\n\t}\n\n\tif Download && ClearCache {\n\t\treturn errors.New(\"task: You can't set both --download and --clear-cache flags\")\n\t}\n\n\tif Global && Dir != \"\" {\n\t\treturn errors.New(\"task: You can't set both --global and --dir\")\n\t}\n\n\tif Output.Name != \"group\" {\n\t\tif Output.Group.Begin != \"\" {\n\t\t\treturn errors.New(\"task: You can't set --output-group-begin without --output=group\")\n\t\t}\n\t\tif Output.Group.End != \"\" {\n\t\t\treturn errors.New(\"task: You can't set --output-group-end without --output=group\")\n\t\t}\n\t\tif Output.Group.ErrorOnly {\n\t\t\treturn errors.New(\"task: You can't set --output-group-error-only without --output=group\")\n\t\t}\n\t}\n\n\tif List && ListAll {\n\t\treturn errors.New(\"task: cannot use --list and --list-all at the same time\")\n\t}\n\n\tif ListJson && !List && !ListAll {\n\t\treturn errors.New(\"task: --json only applies to --list or --list-all\")\n\t}\n\n\tif NoStatus && !ListJson {","sourceCodeStart":200,"sourceCodeEnd":236,"githubUrl":"https://github.com/go-task/task/blob/385e5ad92af02877b6d7cf9dcc963b5ed916e70a/internal/flags/flags.go#L200-L236","documentation":"Flag validation error raised by the Validate function that runs after CLI parsing before any task executes. It fires when the user passes --output-group-begin (start marker for grouped output) but the output mode itself is not 'group', so the marker would be silently ignored. Fix by adding --output=group or removing --output-group-begin.","triggerScenarios":"Running `task --output-group-begin <str>` without also passing `--output=group`, i.e. Output.Group.Begin is non-empty while Output.Name != \"group\".","commonSituations":"Adding group tuning flags to a command that already sets --output interleaved or prefixed; DOTENV/env-var config (TASK_X_OUTPUT_GROUP_BEGIN style) leaking into a non-group output setup.","solutions":["Add `--output=group` to the same invocation","Remove --output-group-begin if you don't want group output","Check env/config files that may set the group-begin value unconditionally"],"exampleFix":"# before\ntask --output prefixed --output-group-begin \"=== \"\n\n# after\ntask --output group --output-group-begin \"=== \"","handlingStrategy":"validation","validationCode":"if flags.Output.Name != \"group\" && flags.Output.Group.Begin != \"\" {\n\treturn errors.New(\"--output-group-begin requires --output=group\")\n}","typeGuard":null,"tryCatchPattern":"if err := flags.Validate(); err != nil {\n\tif strings.Contains(err.Error(), \"--output-group-begin\") {\n\t\tfmt.Fprintln(os.Stderr, \"add --output=group or drop --output-group-begin\")\n\t\tos.Exit(2)\n}\n\treturn err\n}","preventionTips":["Always pair group tuning flags (--output-group-begin/end/error-only) with --output=group","Avoid unconditionally exporting group-output env vars in dotfiles","Keep output style and its modifiers configured in one place"],"tags":["cli","flags","output","go-task"],"backgroundTag":"mutually-exclusive-flags","analyzedSha":"385e5ad92af02877b6d7cf9dcc963b5ed916e70a","analyzedAt":"2026-09-05T09:01:05.226Z","contentChangedAt":"2026-09-05T09:01:05.226Z","schemaVersion":2},"datasetVersion":"2026-09-12T12:17:11.808Z"}