Phase 4 of plans/exit.md: the aux/terminal sub-entrypoints. pkg/auxents and
pkg/terminals are now os.Exit-free; even the dispatchers return exit codes
instead of exiting.
- auxents.Dispatch returns (handled bool, exitCode int); entrypoint.Main --
the one sanctioned exit point -- exits with the code.
- terminals.Dispatch returns an exit code; the climain caller wraps it in a
lib.ExitRequest, which also retires the 'terminal did not exit the process'
panic.
- Usage functions (hex, unhex, lecat, termcvt, repl, script, regtest) no
longer take an exitCode parameter and exit; call sites print usage and
return the code explicitly.
- Inner I/O helpers (hexDumpFile, unhexFile, lecatFile, termcvtFile) return
errors; each sub-main prints 'mlr {verb}: ...' as before and returns 1.
lecatFile formerly looped forever on a non-EOF read error; it now returns
the error.
- The regtest directory walk (Execute / executeSinglePath /
executeSingleDirectory / hasCaseSubdirectories) plumbs errors up to
RegTestMain; regression_test.go updated for the new Execute signature.
Stderr messages and exit codes are unchanged across mlr aux-list, hex, unhex,
lecat, termcvt, help, version, repl, script, and regtest surfaces (checked by
hand); all 4779 regression cases pass; make lint is clean; docs rebuild with
zero churn.
Co-authored-by: Claude Fable 5 <noreply@anthropic.com>
* Rebuild docs: help-catalog index count drifted on main (666 -> 667)
Pre-existing drift from a recent catalog addition; surfaced by make dev.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
* Remove os.Exit callsites below the entrypoint: phase 1 (plans/exit.md)
Phase 1 of plans/exit.md: the mechanical swaps, plus the single-exit-point
scaffolding.
- New sentinel lib.ExitRequest{Code} (io.EOF-style control flow): returned by
code paths that have already printed what they wanted (--version, -h,
'put --explain' on a valid expression, 'put -x') instead of exiting mid-stack.
- pkg/entrypoint: new exitOnError() maps errors to exit codes in one place:
ErrHelpRequested -> 0, ErrUsagePrinted -> 1, ExitRequest -> its code,
anything else printed (JSON if --errors-json) -> 1.
- pkg/climain: version/help/usage/validation exits become returned errors;
the ErrHelpRequested/ErrUsagePrinted -> exit translation moves up to the
entrypoint; loadMlrrcOrDie becomes error-returning loadMlrrcFiles.
- Transformer ParseCLI/constructor exits -> returned errors (cut,
having_fields, nest, reorder, merge_fields, reshape, rename, split, tee,
subs, put_or_filter). merge_fields' bad-regex message formerly mis-reported
itself as coming from the cut verb; tee's unrecognized-option exit was
formerly silent; split/tee constructor failures formerly exited without
printing the constructor's error.
- YAML/JSON record-writer marshal errors -> returned through Write, matching
the CSV writer's error path.
- lib.WriteTempFileOrDie -> WriteTempFile (string, error); its sole caller
(regtest diff helper) degrades gracefully.
Stderr messages and exit codes are byte-identical for all regression-covered
paths (4779 cases pass); runtime Transform-path exits are phase 3.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
* Add lib.NewExitZeroRequest() constructor for exit-0 sentinel returns
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
---------
Co-authored-by: Claude Fable 5 <noreply@anthropic.com>
* Plan: flesh out PR7 (MCP server + Agent Skill) design
stdio transport (no HTTP port), mlr mcp terminal in the main binary,
SDK-vs-handroll decision, tool list, in-process vs subprocess split,
run-tool safety (--no-shell prerequisite), single-sourced skill, tests.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
* Add mlr mcp: MCP server + agent playbook; --no-shell gate (#2098 PR7)
New terminal `mlr mcp` runs a Model Context Protocol server over stdio
(spawned by MCP clients; no network port), exposing five tools --
list_capabilities, which, validate_dsl, describe_data, run -- plus an
agent playbook as MCP prompt/resource. Catalog tools are served
in-process from the help registries; the rest subprocess this same
binary with MLR_ERRORS_JSON=1, a timeout, and an output cap.
Prerequisite: a new --no-shell flag / MLR_NO_SHELL env var (one-way
gate) disables the DSL system/exec functions, piped redirects, and
--prepipe/--prepipex; the MCP server sets it on the commands it runs
unless started with --allow-shell.
Adds the github.com/modelcontextprotocol/go-sdk dependency.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
* Force LF checkout for the embedded SKILL.md (Windows CI fix)
go:embed embeds checkout bytes, so a CRLF checkout on Windows made the
embedded playbook differ per platform and failed
TestPlaybookHasFrontmatter. Pin the file to eol=lf in .gitattributes.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
* Move no-shell test DSL into per-case mlr files (Windows CI fix)
Inline single-quoted DSL in cmd files is mangled by the Windows shell
(single quotes are not quote characters there); the harness's
put -f ${CASEDIR}/mlr pattern avoids shell quoting entirely.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
---------
Co-authored-by: Claude Fable 5 <noreply@anthropic.com>
* Tier-2 structured verb options: OptionSpec, initial migration (#2098)
PR 3 of the AI-friendly roadmap (plans/plan-2098-llm.md).
Infrastructure:
- Add OptionSpec{Flag,Arg,Type,Desc,Repeatable,Values} to
pkg/transformers/aaa_record_transformer.go alongside TransformerSetup.
Type is one of: bool, string, int, float, csv-list, regex, filename,
format, enum. For type=="enum", Values lists the valid choices.
- Add Options []OptionSpec to TransformerSetup (nil = not yet migrated).
- Emit Options in VerbInfoForJSON (omitempty so unmigrated verbs stay
backward-compatible; agents check key presence for Tier-2 availability).
UsageText is always present as the Tier-1 prose fallback.
- Add VerbOptionsNilCheck() in aaa_verb_options_check.go: progress report
of migrated vs. unmigrated verbs, analogous to FLAG_TABLE.NilCheck().
- Wire verb-options-nil-check into mlr help (internal/docgen section).
Initial migration (5/70 verbs):
- nothing: empty Options (no verb-specific options, explicitly migrated)
- cat: -n (bool), -N (string), -g (csv-list), --filename, --filenum (bool)
- head: -g (csv-list), -n (int)
- tail: -g (csv-list), -n (int)
- tee: -a, -p (bool)
Tests:
- 5 new unit tests in aaa_transformer_json_test.go covering migrated/
unmigrated paths, field population, JSON round-trip, and key-presence.
- Regression test case 0003: mlr help verb-options-nil-check golden output.
Co-Authored-By: Claude Sonnet 4.6 (1M context) <noreply@anthropic.com>
* Migrate all 70 verbs to structured OptionSpec; bump catalog schema to v2
Completes the Tier-2 migration started in the previous commit. Every verb
in TRANSFORMER_LOOKUP_TABLE now has a non-nil Options field.
- Workflow-migrated all 65 remaining verbs. Each Setup var now carries
Options: []OptionSpec{...} with Flag/Arg/Type/Desc fields. Verbs with
no verb-specific options (altkv, check, group-like, nothing, etc.) use
an empty slice to signal "migrated but no options."
- Drop `omitempty` from VerbInfoForJSON.Options: empty slices were silently
dropped, making migrated-no-option verbs indistinguishable from unmigrated
ones in JSON. Without omitempty: null=unmigrated, []=migrated-no-options,
[...]= migrated-with-options. Bump catalogSchemaVersion 1→2 for this shape
change.
- Replace the two "unmigrated-verb" unit tests (which used stats1 as an
example) with TestAllVerbsFullyMigrated (asserts every verb has non-nil
Options) and TestAllVerbsHaveOptionsKeyInJSON (asserts every migrated
verb emits the "options" key in JSON).
- Regenerate test/cases/cli-help/0003/expout: now reads
"Verb options migration: 70/70 migrated."
Co-Authored-By: Claude Sonnet 4.6 (1M context) <noreply@anthropic.com>
* Add --errors-json structured error output (#2098)
PR 4 of the AI-friendly roadmap (plans/plan-2098-llm.md).
Agents previously had to regex-match English prose to branch on error
kind; this PR lets them do it structurally.
Interface:
- mlr --errors-json <bad command> emits a JSON object to stderr and
exits 1; same behavior as prose path but machine-readable.
- MLR_ERRORS_JSON=1 (truthy) is the env-var equivalent.
- Without the flag, prose output is byte-for-byte unchanged.
JSON shape: {error, kind, token, verb, hint, did_you_mean[]}
Error kinds: unknown-verb, unknown-flag, verb-option-error, generic.
Implementation:
- New pkg/climain/errors_json.go: CLIError typed error, StructuredError
DTO, WantErrorsJSON pre-scan, Levenshtein edit distance, topMatches,
EmitStructuredError.
- Convert two direct os.Exit sites in parseCommandLinePassOne (unknown
verb, unknown flag) to return CLIError values; verb-option-error
likewise returns CLIError from pass-one ParseCLIFunc handling.
- parseCommandLinePassOne gains an error return; ParseCommandLine
propagates it.
- entrypoint.go pre-scans os.Args for --errors-json before calling
ParseCommandLine; routes errors to EmitStructuredError or printError.
- did_you_mean: Levenshtein nearest-match over verb catalog, flag
catalog, or the verb own OptionSpec flags (PR3 catalog) for
verb-option-error. Closes the self-correction loop the catalog
enables.
- --errors-json registered in Miscellaneous flags so it appears in
mlr --help and is not treated as an unrecognized flag.
Tests: 16 unit tests covering Levenshtein, topMatches, threshold,
WantErrorsJSON, CLIError interface, and all categorize paths.
Co-Authored-By: Claude Sonnet 4.6 (1M context) <noreply@anthropic.com>
---------
Co-authored-by: Claude Sonnet 4.6 (1M context) <noreply@anthropic.com>
* refine the plan
* Fix all staticcheck lint findings (uncapped)
golangci-lint's default max-same-issues=3 was hiding most of the backlog:
the true pre-fix count was 69 staticcheck findings, not 34. This fixes all
of them, driving staticcheck to zero:
- ST1023/QF1011 (37): omit explicit types inferred from the RHS
- S1009/S1031 (15): drop redundant nil checks before len()/range
- SA9003 (9): remove comment-only empty branches, keeping the comments
- QF1007 (3): merge conditional assignment into declaration
- QF1006 (3): lift break conditions into loop conditions
- QF1001 (3): apply De Morgan's law / name the negated predicate
Also updates plans/lintfixes.md with the cap discovery and the corrected
errcheck picture (1202 uncapped, ~949 of them fmt.Fprint*).
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
* Drive errcheck to zero: config for bulk categories, propagate real errors
Adds .golangci.yml with errcheck exclude-functions for fmt.Fprint* (usage
printers), (*bufio.Writer).Write/WriteString (sticky errors, surfaced at the
now-checked final Flush), and (*strings.Builder).WriteString; pins
max-issues-per-linter/max-same-issues to 0 so CI reports true counts.
Real error paths now propagate instead of being dropped:
- Finalize{Reader,Writer}Options in join/put/filter/split/tee and the
repl/script entry points: 'mlr join -i badformat' now errors instead of
silently using wrong separators
- final output-stream Flush in pkg/stream: write failure no longer exits 0
- DSL emit/print/dump redirect writes, matching their sibling branches
- CSV writer WriteCSVRecordMaybeColorized, close-time Flush in file output
handlers, ENV[...] Setenv, REPL record-write and redirect-close errors
- termcvt write-side Close before rename (had "TODO: check return status")
The rest are deliberate ignores, marked with _ = and a comment where the
reason isn't obvious: unset-of-missing-path no-ops, read-side closes,
mid-stream FlushOnEveryRecord, init-time strftime registrations, in-memory
usage-capture pipes, and regtest-harness env/temp-file teardown.
golangci-lint now reports 0 issues on ./cmd/mlr ./pkg/... with all caps off.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
---------
Co-authored-by: Claude Fable 5 <noreply@anthropic.com>
The io/ioutil package has been deprecated as of Go 1.16 [1]. This commit
replaces the existing io/ioutil functions with their new definitions in
io and os packages.
[1]: https://golang.org/doc/go1.16#ioutil
Signed-off-by: Eng Zer Jun <engzerjun@gmail.com>
