utils/ruby.sh: test_ruby(): keep temporary variables local

[maxim-belkin]

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A couple of variables were not made local in 87931e1.

@Bo98, what's the logic behind

[[ -z "$HOMEBREW_MACOS" ]] && TERMINFO_DIRS="$vendor_ruby_terminfo"

lines? I couldn't find a PR/Issue associated with 87931e1, so not sure where to ask other than here. Don't we need TERMINFO_DIRS on Linux as well?

[Bo98]

Don't we need TERMINFO_DIRS on Linux as well?

[[ -z "$HOMEBREW_MACOS" ]] means not macOS, so that line is running on Linux.

[maxim-belkin]

Right, my bad. So, why doesn't macOS need that. Can we set it in one place only? For example, right before export?

[Bo98]

So, why doesn't macOS need that.

Because on macOS we use system ncurses for portable Ruby, so we let system ncurses handle terminfo itself.

The Linux build has its own ncurses build and so has its own bundled terminfo.

Can we set it in one place only? For example, right before export?

As long as we make sure it only applies when portable Ruby is going to be used - not when it happens to find some system Ruby.

[MikeMcQuaid]

Thanks @maxim-belkin!