feat(help): add --help to builtins and extend help command by matt-dz · Pull Request #129 · DataDog/rshell

matt-dz · 2026-03-19T13:28:21Z

Summary

Added `--help` to `break`, `continue`, `exit` — matches bash builtin behaviour (stdout, exit code 2, byte-for-byte verified against debian:bookworm-slim)
Extended `help` builtin to support `help ` — displays detailed help for any command
- For commands with `--help` (cat, grep, etc.): dynamically invokes the command and captures output — no static strings to maintain
- For commands without `--help` (echo, true, false): uses a static `Help` field on the `Command` struct
Kept `echo`, `true`, `false` matching bash builtin behaviour — these ignore `--help` silently, matching bash
Added `Help` field to `Command` and `CommandMeta` structs for fallback help text
`help` with no args still lists all commands; `help ` shows detailed help; extra operands are rejected

Test plan

🤖 Generated with Claude Code

- break, continue, exit: match bash builtin behaviour (stderr, exit code 2) - echo, true, false: match GNU coreutils behaviour (stdout, exit code 0) - Add scenario tests for all 6 commands - Update existing tests that expected --help to be ignored Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

matt-dz · 2026-03-19T13:33:35Z

@codex conduct a comprehensive security and code review

chatgpt-codex-connector

💡 Codex Review

Here are some automated review suggestions for this pull request.

Reviewed commit: 678dd226cf

ℹ️ About Codex in GitHub

Your team has set up Codex to review pull requests in this repo. Reviews are triggered when you

Open a pull request for review
Mark a draft as ready
Comment "@codex review".

If Codex has suggestions, it will comment; otherwise it will react with 👍.

Codex can also answer questions or update the PR. Try commenting "@codex address that feedback".

false is a guaranteed failure primitive and should always exit non-zero, even when displaying help text. Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

echo is a shell builtin — bash's builtin echo treats --help as literal text, not a flag. Reverts to bash-compatible behaviour. Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

true and false are shell builtins — bash ignores all arguments silently. Reverts to bash-compatible behaviour where --help is a no-op. Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

matt-dz · 2026-03-19T14:00:41Z

@codex conduct a comprehensive security and code review

chatgpt-codex-connector

💡 Codex Review

Here are some automated review suggestions for this pull request.

Reviewed commit: a1a49073cd

ℹ️ About Codex in GitHub

Your team has set up Codex to review pull requests in this repo. Reviews are triggered when you

Open a pull request for review
Mark a draft as ready
Comment "@codex review".

If Codex has suggestions, it will comment; otherwise it will react with 👍.

Codex can also answer questions or update the PR. Try commenting "@codex address that feedback".

Add per-command help text to all 26 builtins via a new Help field on the Command struct. Running 'help <command>' now displays detailed usage for that command, matching the output of '<command> --help' where supported. This is especially useful for builtins like echo, true, and false that don't support --help (matching bash builtin behaviour). Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Bash emits builtin --help output on stdout. Our break, continue, and exit builtins incorrectly wrote to stderr, breaking patterns like 'break --help | head' and 'break --help >file'. Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Re-enable bash comparison assertions for break, continue, and exit help scenarios. Add trailing spaces on blank lines to match bash's exact output format. All three scenarios now pass byte-for-byte against debian:bookworm-slim bash. Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

matt-dz · 2026-03-19T14:30:04Z

@codex conduct a comprehensive security and code review

chatgpt-codex-connector

💡 Codex Review

Here are some automated review suggestions for this pull request.

Reviewed commit: 16731f760d

ℹ️ About Codex in GitHub

Your team has set up Codex to review pull requests in this repo. Reviews are triggered when you

Open a pull request for review
Mark a draft as ready
Comment "@codex review".

If Codex has suggestions, it will comment; otherwise it will react with 👍.

Codex can also answer questions or update the PR. Try commenting "@codex address that feedback".

…trings Replace static Help field strings on 23 commands with dynamic invocation: help <command> now calls the command's handler with --help and captures the output. Only echo, true, and false retain static Help text since they don't handle --help (matching bash builtin behaviour). This eliminates 418 lines of duplicated help text that would drift out of sync whenever flags are added or changed. Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

help echo typo now prints usage and exits 1 instead of silently ignoring the extra argument. Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

matt-dz · 2026-03-19T14:55:05Z

@codex conduct a comprehensive security and code review

chatgpt-codex-connector · 2026-03-19T15:04:49Z

Codex Review: Didn't find any major issues. 🎉

ℹ️ About Codex in GitHub

Your team has set up Codex to review pull requests in this repo. Reviews are triggered when you

Open a pull request for review
Mark a draft as ready
Comment "@codex review".

If Codex has suggestions, it will comment; otherwise it will react with 👍.

Codex can also answer questions or update the PR. Try commenting "@codex address that feedback".

Replace single-line escaped strings with multi-line string constants for break, continue, and exit --help output. Easier to read and maintain. Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

chatgpt-codex-connector Bot reviewed Mar 19, 2026

View reviewed changes

Comment thread builtins/false/false.go Outdated

Comment thread builtins/echo/echo.go Outdated

Comment thread builtins/true/true.go Outdated

matt-dz and others added 3 commits March 19, 2026 09:44

fix: preserve non-zero exit status for false --help

2db04a0

false is a guaranteed failure primitive and should always exit non-zero, even when displaying help text. Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

revert: keep echo --help as literal text

ee311f5

echo is a shell builtin — bash's builtin echo treats --help as literal text, not a flag. Reverts to bash-compatible behaviour. Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

revert: keep true and false silent on --help

a1a4907

true and false are shell builtins — bash ignores all arguments silently. Reverts to bash-compatible behaviour where --help is a no-op. Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

chatgpt-codex-connector Bot reviewed Mar 19, 2026

View reviewed changes

Comment thread builtins/break/break.go Outdated

Comment thread tests/scenarios/cmd/exit/help.yaml Outdated

matt-dz and others added 3 commits March 19, 2026 10:14

chatgpt-codex-connector Bot reviewed Mar 19, 2026

View reviewed changes

Comment thread builtins/help/help.go

matt-dz and others added 2 commits March 19, 2026 10:49

fix(help): reject extra operands in help command

cb478ab

help echo typo now prints usage and exits 1 instead of silently ignoring the extra argument. Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

matt-dz marked this pull request as ready for review March 19, 2026 15:06

matt-dz requested review from AlexandreYang, astuyve, julesmcrt and thieman as code owners March 19, 2026 15:06

matt-dz changed the title ~~feat: add --help to break, continue, exit, echo, true, false~~ feat(help): add --help to builtins and extend help command Mar 19, 2026

matt-dz added the verified/allowed_symbols label Mar 19, 2026

matt-dz enabled auto-merge March 19, 2026 15:09

AlexandreYang reviewed Mar 19, 2026

View reviewed changes

Comment thread builtins/continue/continue.go Outdated

style: use readable helpText constants for inline --help strings

9d66875

Replace single-line escaped strings with multi-line string constants for break, continue, and exit --help output. Easier to read and maintain. Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

matt-dz requested a review from AlexandreYang March 19, 2026 15:20

AlexandreYang approved these changes Mar 19, 2026

View reviewed changes

matt-dz added this pull request to the merge queue Mar 19, 2026

Merged via the queue into main with commit 448c492 Mar 19, 2026
31 checks passed

matt-dz deleted the matt-dz/add-help-flags branch March 19, 2026 15:25

thieman mentioned this pull request Mar 25, 2026

fix(builtins): --help must exit 0 for help, break, and continue #150

Closed

5 tasks

Provide feedback

Saved searches

Use saved searches to filter your results more quickly

feat(help): add --help to builtins and extend help command#129

feat(help): add --help to builtins and extend help command#129
matt-dz merged 10 commits intomainfrom
matt-dz/add-help-flags

matt-dz commented Mar 19, 2026 •

edited

Loading

Uh oh!

matt-dz commented Mar 19, 2026

Uh oh!

chatgpt-codex-connector Bot left a comment

Uh oh!

Uh oh!

Uh oh!

Uh oh!

matt-dz commented Mar 19, 2026

Uh oh!

chatgpt-codex-connector Bot left a comment

Uh oh!

Uh oh!

Uh oh!

matt-dz commented Mar 19, 2026

Uh oh!

chatgpt-codex-connector Bot left a comment

Uh oh!

Uh oh!

matt-dz commented Mar 19, 2026

Uh oh!

chatgpt-codex-connector Bot commented Mar 19, 2026

Uh oh!

Uh oh!

Uh oh!

Reviewers

Assignees

Labels

Projects

Milestone

Development

Uh oh!

2 participants

Conversation

matt-dz commented Mar 19, 2026 • edited Loading Uh oh! There was an error while loading. Please reload this page.

Uh oh!

Summary

Test plan

Uh oh!

matt-dz commented Mar 19, 2026

Uh oh!

chatgpt-codex-connector Bot left a comment

Choose a reason for hiding this comment

💡 Codex Review

Uh oh!

Uh oh!

Uh oh!

Uh oh!

matt-dz commented Mar 19, 2026

Uh oh!

chatgpt-codex-connector Bot left a comment

Choose a reason for hiding this comment

💡 Codex Review

Uh oh!

Uh oh!

Uh oh!

matt-dz commented Mar 19, 2026

Uh oh!

chatgpt-codex-connector Bot left a comment

Choose a reason for hiding this comment

💡 Codex Review

Uh oh!

Uh oh!

matt-dz commented Mar 19, 2026

Uh oh!

chatgpt-codex-connector Bot commented Mar 19, 2026

Uh oh!

Uh oh!

Uh oh!

Reviewers

Assignees

Labels

Projects

Milestone

Development

Uh oh!

2 participants

matt-dz commented Mar 19, 2026 •

edited

Loading