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An option is resolved from the root before the matched command, so a short name means one thing for the whole line

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  • 何か問題がありますか？
#153 コメント 6 件 リアクション 0 件 担当者 0 名 GitHub で見る

@AmirSa12 がすでに取り組んでいます。

2026年10月5日 から。

  • #154 @AmirSa12 による — オープン

評価

難易度
4/5
見積もり時間
3〜5日
初心者へのやさしさ
56/100
issue の種類
バグ
明瞭さ
明確に書かれている
活発さ
活発
技術スタック
javascript, typescript
領域
cli

調査の方向性

RootCommand#shouldCompleteFlags() と #stripOptions() から始め、次に matchCommand() が後者をどのように呼び出し、handleFlagCompletion() が一致したコマンドをどのように使用するかを追跡します。提供されている再現手順を Node で実行し、4 つの argv ケースの補完を比較します。各位置で確定したコマンドにオプションのアリティが従い、コマンドの前にある root オプションがこれまでどおり動作すれば完了です。

索引モデルが issue の本文から書いたものです。

説明

What happens

RootCommand#shouldCompleteFlags() and #stripOptions() decide whether the word after an option is that option's value. Both resolve the option with findOption(this, arg) — the root first — and fall back to the registered commands only when the root does not have it. An option therefore has one arity for the whole line, whichever command the cursor is in.

A CLI whose root carries the program's own options, and whose sub-command gives one of those letters to an option that takes a value, cannot be completed there.

Reproduction
// repro.mjs — `npm i @bomb.sh/[email protected]`, then `node repro.mjs`
import { RootCommand } from '@bomb.sh/tab'

const build = () => {
  const root = new RootCommand()
  root.option('help', 'Display this help message', 'h') // boolean, takes no value

  const serve = root.command('serve', 'Serve the app')
  serve.option('host', 'Host name', c => c('localhost', ''), 'h') // takes a value, same letter
  serve.argument('env', c => {
    c('prod', '')
    c('staging', '')
  })
  return root
}

for (const argv of [
  ['serve', '-h', ''],
  ['serve', '-h', 'localhost', ''],
  ['serve', '--host', ''],
  ['-h', '']
]) {
  process.stdout.write(`${JSON.stringify(argv).padEnd(36)} => `)
  build().parse([...argv])
}

Actual output (@bomb.sh/tab 0.0.22, Node 24.21.0). Each request prints its candidates one per line; they are joined with / here:

["serve","-h",""]                    => prod / staging / :4
["serve","-h","localhost",""]        => :4
["serve","--host",""]                => localhost / :4
["-h",""]                            => serve / :4
  • serve -h <TAB> offers the positional, because -h was read as the root's boolean help. Expected: localhost, the value of the command's --host.
  • serve -h localhost <TAB> offers nothing, because localhost was counted as the positional. Expected: prod, staging.
  • The last two lines are the controls, and both are right: the long name resolves against the command, and -h in front of a command name is the root's.
Why it is not simply "look at the matched command"

stripOptions() is what matchCommand() calls to find the command, so the command is not known when the question is asked. Fixing it means walking the words in order and resolving each option against the command that is settled at that point — the root until a command name is matched, then that command, and so on.

handleFlagCompletion() already resolves against the matched command, so once shouldCompleteFlags() answers correctly for a letter typed behind a command name, the value completion follows.

Related

Issue #110 (closed) is the same family: handlePositionalCompletion() counted words without stripping options. This is the other half — the stripping itself does not know where it is.

Downstream

gunshi (kazupon/gunshi#744) works around it by re-registering the root's entry for that one letter, for the duration of one completion request, and only when the letter was typed behind the matched command's name
(PR #753, corrected in PR #754 — the first attempt re-registered the root's entry under the option's long name, which flipped the arity of --help too). The workaround cannot express the same letter on both sides of a command name, because one Option carries one arity for the request. If the lookup here becomes positional, that workaround is deleted whole.

主要言語
TypeScript
スター
280
フォーク
11
30日以内にマージされた PR はありません

環境構築

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はじめの一歩

  1. issue を最後まで読み、次にプロジェクトのコントリビューションガイドを読みます。
  2. 着手することを issue にコメントします — 二人が同じ作業をするのを防げます。
  3. リポジトリをフォークし、ブランチを切って変更します。
  4. issue 番号を参照したプルリクエストを送ります。

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