generate shell completion is changed in v0.71.0

[daeho-ro]

Hello,

I have noticed that the generating shell completion is a bit weird now,

bindgen --generate-shell-completions 
error: a value is required for '--generate-shell-completions <SHELL>' but none was supplied
  [possible values: bash, elvish, fish, powershell, zsh]

For more information, try '--help'.

The option --generate-shell-completions requires shell input and so put it leads to an error

bindgen --generate-shell-completions bash
error: the following required arguments were not provided:
  <HEADER>

Usage: bindgen <FLAGS> <OPTIONS> <HEADER> -- <CLANG_ARGS>...

For more information, try '--help'.

It seems that the usage is changed and not documented on the command.

This is happen on the homebrew CI here,

• bindgen 0.71.1 Homebrew/homebrew-core#200347

Thanks,

[jbeich]

Duplicate of #2677 (comment) ? Workaround: pass a dummy header: bindgen --generate-shell-completions bash whatever