Show alias value

[mgkurtz]

In #532 some folks (@akainth015 and @slacksystem) asked for a feature to list the expansion of the current alias together with the other completions. Here it is in two lines for your zshrc:

if is-at-least 5.9; then
  _expand_alias_and_continue() { _expand_alias; return 1 }
  zstyle ':completion:*' completer _expand _expand_alias_and_continue _complete _complete:-fuzzy _correct _approximate _ignored
fi

How it works

Completion stops when a completer returns success. So, we just have our _expand_alias wrapper return failure in all cases.

The zstyle configuration is just that of zsh-autocomplete with our _expand_alias_and_continue added.

As an example, the completion listing when I type gs using the https://github.com/davidde/git plugin now roughly looks like

alias
git status
command
gs gsbj gsdj gsdj500 gsettings gsftopk gsh gshsf gslj gslp gsnd gss gst gsta gstack gstd gstl gstls gstp gstpop gstsl gstsp gsub gsuba gsubi gsubpl gsubplom gsubs gsubu gsw gswc

When my cursor is just on ls --help, it shows the global coloring --help alias I configured like

option
--help -- display help information
alias
--help 2>&1 | bat --language=help --plain

What I tried before

_expand_alias_and_complete() { _expand_alias _complete }
zstyle ':completion:*' completer _expand_alias_and_complete _ignored

The _alternative utility function (described in man zshcompsys) provides three features: forming unions and tagging and describing things. We only use the former, so the function

_expand_alias_and_complete() { _alternative ::_expand_alias ::_complete }

forms the union of _expand_alias and _complete.
(The :: in the _alternative arguments are for <tag>:<description>:, but as both a tag and a description get provided by _expand_alias respectively _complete anyway, we may keep them empty.) Wrong: It messes up with the descriptions already provided.

The configuration

zstyle ':completion:*' completer _expand_alias_and_complete _ignored

says to use our own function in place of _complete in every completion context.

The :completion:* stands for every completion context. This is necessary for global aliases to work. If you only want the alias to be shown, when in command position use :completion:*:::: which says: we are in no context yet, that is at the beginning of the command line, although we may use some widget (the *), e.g. for listing the completions as zsh-autocomplete does, when the completions fill the entire screen.

What others tried before

The naïve

 zstyle ':completion:*' completer _expand_alias _complete _ignored

does not solve this, as it stops as soon as one of the three completers provides a result. So it either shows an alias expansion or normal completions or ignored completions.

What I tried before

Up to now, I solved this for my own by adding a line

_expand_alias "$@" && ret=0

in zsh-autocomplete’s Completions/_autocomplete__command which simply adds the alias expansion to the list of command completions. This could be made configurable via zstyle ':autocomplete:*' expand-alias on by adding an extra condition:

zstyle -t ":autocomplete:$curcontext" expand-alias && _expand_alias "$@" && ret=0

While this works, it looks somewhat hacky to place the expansion among all the other completions.

[alexwforsythe]

I upgraded zsh-autocomplete for the first time in a couple years--along with a bunch of other configs--and started noticing the commands group was empty when other completers returned matches, e.g.:

% gcp
-- external command --
-- alias --
gcp   gcP   gcpa  gcpc

I was reading the zsh docs and it says:

If the name given is the empty string the name of the tag for the matches will be used as the name of the group. So, to have all different types of matches displayed separately, one can just set:

zstyle ':completion:*' group-name ''

If you use the zsh-users/zsh-completions plugin, like me, it may set that style for you. It will be overridden for the -command- scope by this plugin, though:

zsh-autocomplete/Functions/Init/.autocomplete__config

Line 96 in 316c588

builtin zstyle ':completion:*:-command-:*' group-name commands

This appears to have been taken from the paragraph in the zsh docs right above the one I quoted. So, I overrode that context in my own config:

# .zshrc, after sourcing zsh-autocomplete
zstyle ':completion:*:-command-:*' group-name ''

Now, both groups have entries and they're in the correct order (defined by my group-order zstyle):

% gcp
-- alias --
gcp   gcP   gcpa  gcpc
-- external command --
gcp