Omit aliases from completions

[MikeMcQuaid]

Fixes https://github.com/orgs/Homebrew/discussions/6836

• Avoid suggesting internal aliases because they duplicate canonical commands.
• Keep alias expansion for option completion after users type an alias.
• Regenerate bash, fish, zsh and internal command completion data.

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[Copilot]

Pull request overview

This PR updates Homebrew’s shell completion generation to omit internal command aliases from top-level command suggestions (so users see canonical commands only), while still expanding internal aliases when the user types one so option/subcommand completion continues to work.

Changes:

• Stop including internal command aliases in the cached/internal command lists used by completions.
• Add internal-alias expansion hooks in bash/fish completions and adjust zsh generation to avoid emitting per-alias completion functions.
• Add tests to ensure aliases are omitted from command suggestion lists but still expand correctly for completion dispatch.

Reviewed changes

Copilot reviewed 10 out of 10 changed files in this pull request and generated no comments.

Show a summary per file

File	Description
Library/Homebrew/test/completions_spec.rb	Adds expectations that bash/zsh/fish completion generation omits alias command suggestions but retains alias expansion for dispatch.
Library/Homebrew/test/commands_spec.rb	Adds coverage ensuring rebuilt command lists don’t include internal aliases.
Library/Homebrew/completions/fish.erb	Introduces alias expansion helper and filters out internal aliases from suggested commands.
Library/Homebrew/completions/bash.erb	Filters alias commands from suggestions and expands internal aliases before dispatching to subcommand completion.
Library/Homebrew/completions.rb	Generates completions from canonical command lists (no aliases) and injects alias-expansion data into templates.
Library/Homebrew/commands.rb	Ensures rebuilt completion command lists omit internal aliases by default.
completions/zsh/_brew	Regenerated zsh completion output without per-alias completion functions.
completions/internal_commands_list.txt	Regenerated internal command list omitting internal alias entries.
completions/fish/brew.fish	Regenerated fish completion output with alias expansion and alias omission in suggestions.
completions/bash/brew	Regenerated bash completion output with alias expansion and alias omission in suggestions.

Comments suppressed due to low confidence (2)

Library/Homebrew/completions/bash.erb:165

• __brew_list_aliases appears to be dead code now: it's defined but no longer referenced anywhere in the bash completion script (it used to be used by __brew_complete_commands). Consider removing this function (and the homebrew-aliases comment) to reduce generated completion size and avoid maintaining unused code.

# https://github.com/Homebrew/homebrew-aliases
__brew_list_aliases() {
  local aliases_dir="${HOME}/.brew-aliases"
  local pattern="^# alias: brew ([[:alnum:]-]+)$"
  local -a aliases

  [[ ! -d ${aliases_dir} ]] && return

  for file in "${aliases_dir}"/*; do
    [[ ! -f ${file} ]] && continue
    while read -r line; do
      if [[ ${line} =~ ${pattern} ]]; then
        aliases+=("${BASH_REMATCH[1]}")
        break
      fi
    done < "${file}"
  done
  [[ -n ${aliases[*]+"${aliases[*]}"} ]] && echo "${aliases[@]}"
}

completions/bash/brew:168

• __brew_list_aliases is defined but not referenced anywhere in the generated bash completion file anymore. It looks like leftover code from when command completion appended homebrew-aliases entries; removing it would reduce file size and avoid carrying unused logic.

# https://github.com/Homebrew/homebrew-aliases
__brew_list_aliases() {
  local aliases_dir="${HOME}/.brew-aliases"
  local pattern="^# alias: brew ([[:alnum:]-]+)$"
  local -a aliases

  [[ ! -d ${aliases_dir} ]] && return

  for file in "${aliases_dir}"/*; do
    [[ ! -f ${file} ]] && continue
    while read -r line; do
      if [[ ${line} =~ ${pattern} ]]; then
        aliases+=("${BASH_REMATCH[1]}")
        break
      fi
    done < "${file}"
  done
  [[ -n ${aliases[*]+"${aliases[*]}"} ]] && echo "${aliases[@]}"
}

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