Suppress "completion installed" text in Caveats about brew HOT 5 OPEN

Another potential option here: given it looks like detection is not really possible maybe these could just be output a single time regardless of how many formulae are installed/upgraded at the end of all installations?

from brew.

Looks like for detection if it has been run in the current shell could be by inspecting BASH_COMPLETION_VERSINFO. Assuming there's similar vars for zsh, fish, etc.

from brew.

Looks like for detection if it has been run in the current shell could be by inspecting BASH_COMPLETION_VERSINFO. Assuming there's similar vars for zsh, fish, etc.

@jubr Can you investigate this more? If we can automatically detect if this message is redundant I agree it may make sense to remove these messages.

HOMEBREW_CAVEAT_COMPLETIONS with future values like suppress, show, suppress-when-detected-in-shell.

Going from "no configuration" to "four different settings" feels excessive. Let's focus on the problem to be solved for now and we can figure out what's best based on what's e.g. possible from the shell.

from brew.

Looks like for detection if it has been run in the current shell could be by inspecting BASH_COMPLETION_VERSINFO

I don't think that is available in bash-completion (v1) for system bash users. This has more installs than bash-completion@2 in last 90 days and last 365 days.

Some tricky parts for shell detection:

1. brew is a bash script. Not sure if possible to see corresponding zsh (e.g. fpath/FPATH/_comps) and fish (e.g. fish_complete_path) variables.
2. brew sanitizes the environment. By the time caveats are printed, the BASH_* variables have been removed from environment.

From quick glance, a suppress-when-detected-in-shell feature wouldn't be possible other than maybe brew fish (since we don't need variables there other than particular shell).

If so, the options would then be a full opt out flag or maybe some sort of show-once-per-formula if we could store info in tab.

from brew.

I just stumbled upon this issue and would like to express my opinion: as a Homebrew user, I really like when I brew install something and see "zsh completion has been installed". I just really like shell completions. I think it's a good default to print information about installing completion files.

I agree with #2110 that "Caveats" is not maybe the best place for it, though.

from brew.