Shell completion needs improvement

[dveeden]

Feature Request

There is tiup completion but it has multiple issues:

• It doesn't accept /bin/bash as valid value (Fixed in cmd: use SHELL from environment for completion #1455 )
• It doesn't use the SHELL from the environment (Fixed in cmd: use SHELL from environment for completion #1455 )
• It doesn't get installed by default. Maybe install.sh should run tiup completion bash > /etc/bash_completion.d/tiup ?
• Components like cluster and playground are not excluded in the shell completion.

I think tiup components are a bit similar to git commands. And for git there is this: https://github.com/git/git/blob/master/contrib/completion/git-completion.bash to allow additional tools like git-extras

Maybe tiup should have a list of known/registered components and then run the component like tiup <component> completion which then can emit the right output similar to what git uses.

[nexustar]

thanks for your contribution. cobra has completion support since 1.2.0 . So we will use cobra build-in function and trick it at #1688

[nexustar]

tiup has usable shell completion since v1.10.0