Rewrite completions for meson to expose meson commands with their
options and subcommands. New completions are based on the meson 1.0.
Subcommands were introduced in meson 0.42.0 (August 2017), so new
completions will only work for versions after 0.42.0. At this moment,
even oldstable Debian (buster) has meson 0.49.2 -- which means it is
unlikely someone will be affected.
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Co-authored-by: Mahmoud Al-Qudsi <mqudsi@neosmart.net>
Their names are not perfect, so let's keep them as internal functions,
until we figure out how/if we want to expose this.
This reverts 0445126c2 (Undunder __fish_is_nth_token, 2021-06-29) (but I
did it without "git revert").
Closes#8008
We keep __fish_is_nth_token for compatibility and edit the
implementations of __fish_is_nth_token, __fish_is_first_token and
__fish_is_token_n to use fish_is_nth_token
