tools: add zsh completions

[rpigott]

N.B. To try it out place the completion script called "_xkbcli" somewhere in your $fpath.

Please check that the meson bits are reasonable.

[rpigott]

I like to provide completions for the layouts/models/options, etc. but not sure there's a good way without parsing xkbcli output with yq or something. I don't particularly mind doing that, but obviously its better if we don't depend on an external tool.

Do you think it would be possible to give xkbcli a more shell-parse friendly output?

[rpigott]

Added some PoC RMLVO completers in the second commit, using yq.

[wismill]

Great addition! Thanks!

[rpigott]

The options RMLVO completer isn't working perfectly, as the group names don't always match the options prefixes:

$ XKB_DEFAULT_OPTIONS=<TAB>
altwin        -- Alt and Win behavior
caps          -- Caps Lock behavior
compat        -- Compatibility options
compose       -- Position of Compose key
ctrl          -- Ctrl position
currencysign  -- Currency signs
custom        -- Miscellaneous options
esperanto     -- Esperanto letters with superscripts
fkeys         -- Function keys
grp_led       -- Use keyboard LED to show alternative layout
grp           -- Switching to another layout
japan         -- Japanese keyboard options
keypad        -- Layout of numeric keypad
korean        -- Korean Hangul/Hanja keys
kpdl          -- Numeric keypad Delete behavior
lv2           -- Key to choose the 2nd level
lv3           -- Key to choose the 3rd level
lv5           -- Key to choose the 5th level
mod_led       -- Use keyboard LED to indicate modifiers
nbsp          -- Non-breaking space input
solaris       -- Old Solaris keycodes compatibility
terminate     -- Key sequence to kill the X server

$ XKB_DEFAULT_OPTIONS=compat:<TAB> # these aren't real options since they don't actually being with "compat:"
alupckeys             -- Apple Aluminium emulates Pause, PrtSc, Scroll Lock
apl                   -- Enable APL overlay characters
both_capslock         -- Both Shifts together enable Caps Lock
both_capslock_cancel  -- Both Shifts together enable Caps Lock; one Shift key disables it
both_shiftlock        -- Both Shifts together enable Shift Lock
break_actions         -- Allow breaking grabs with keyboard actions (warning: security risk)
breaks_caps           -- Shift cancels Caps Lock
debug                 -- Allow grab and window tree logging
jp_oadg109a           -- Japanese Apple keyboards emulate OADG109A backslash
jp_pc106              -- Japanese Apple keyboards emulate PC106 backslash
mac                   -- Numeric keypad always enters digits (as in macOS)
microsoft             -- Num Lock on: digits; Shift for arrows. Num Lock off: arrows (as in Windows)
mod2                  -- Map Hyper to Mod2 (conflict with NumLock)
mod3                  -- Map Hyper to Mod3 (conflict with LevelFive)
mod4                  -- Map Hyper to Mod4 (conflict with Super)
none                  -- Special keys (Ctrl+Alt+<key>) handled in a server
pc                    -- Default numeric keypad keys
pointerkeys           -- Shift + Num Lock enables PointerKeys
shift3                -- Shift does not cancel Num Lock, chooses 3rd level instead
typo                  -- Enable extra typographic characters

I'll think of a better way to present these completions.

[rpigott]

Should be better now, and added more sed implementations.

[rpigott]

@wismill any thoughts?