fix: positional argument completion broken after flags

[murrayju]

Problem

Positional argument completion doesn't work when flags precede the argument. For example:

mycli session logs -f <TAB>    # No completions shown
mycli session logs <TAB>        # Works correctly
mycli session info -o json <TAB> # No completions shown

Fixes #110

Root Causes

Three interacting bugs:

1. handlePositionalCompletion doesn't strip options from args

The method uses previousArgs.length to calculate the positional argument index, but previousArgs still contains flags (e.g., ['session', 'logs', '-f']). This inflates the index past the registered arguments array.

Fix: Call this.stripOptions() on the args at the top of handlePositionalCompletion.

2. parse() early-returns after boolean flags

When the previous arg is a boolean flag and the current completion target is empty (TAB pressed), there's an early return that skips both handleCommandCompletion and handlePositionalCompletion:

if (option && option.isBoolean) {
  this.complete(toComplete);
  return;  // skips positional completion
}

Fix: Remove the early return so control falls through to command and positional completion.

3. Commander adapter marks all options as isBoolean=true

The commander adapter registers every option as boolean, even value-taking ones like --output <format>. The option() method on Command infers isBoolean from argument types — when a string alias is passed, it sets isBoolean=true. This causes stripOptions to not skip the value argument for options like --output json.

Fix: In the commander adapter, detect < or [ in the flag syntax string and pass a no-op handler to force isBoolean=false for value-taking options.

Changes

• src/t.ts: Strip options in handlePositionalCompletion, remove early return in parse()
• src/commander.ts: Add registerOption helper that detects value-taking options and sets isBoolean correctly
• tests/cli.test.ts: Update boolean option tests to expect subcommand completions (not empty output) after boolean flags
• tests/__snapshots__/cli.test.ts.snap: Regenerated snapshots

Testing

All 187 existing tests pass (64 skipped as before — commander and fish integration).

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🦋 Changeset detected

Latest commit: 5cce0df

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 1 package

Name	Type
@bomb.sh/tab	Patch

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commit: 5cce0df

[AmirSa12]

I really enjoyed reviewing this. super detailed and nicely engineered.
Thanks a lot for the effort you put into this.. I really appreciate it 🙌