Completing command name itself in zsh

Question

I have a bunch of ZSH functions which are pretty verbose, and I'd like to use zsh completion on them. Example:

qq-enum-dns-txfr-host
qq-enum-dns-brute-rev
qq-enum-dns-tcpdump
qq-enum-web-php-lfi-logfile
qq-enum-smb-tcpdump
qq-enum-web-php-ffuf-common-php
qq-enum-ftp-tcpdump

When I type qq-tcpTab I'd like to get completions of:

qq-enum-dns-tcpdump
qq-enum-smb-tcpdump
qq-enum-ftp-tcpdump

All the documentation I can find deals with how to complete arguments to a given command or function, but doesn't say how to use the substring (not prefix) completion to figure out which function to use in the first place.

I guess I could refactor so that each function is instead an argument to a qq command. But is there a simpler way I'm missing?

score 3 · Accepted Answer · answered Mar 16 '20 at 14:28

You can configure the completion system extensively with the zstyle builtin. By default, completion only tries to add a suffix, but you can change this with a matcher-list style. To apply the style to all completions:

zstyle ':completion:*' matcher-list …

To apply the style only when the context is a command, and only for commands that are functions:

zstyle ':completion:*:*:-command-:*:functions matcher-list …

What goes after matcher-list is a list of completion matching control specifications. Zsh tries them in order, and stops as soon as one finds a match. Use the empty specification to just add a suffix; you'll usually want this first except in very specific contexts where this makes it hard to reach some completions. You can use an r specification to allow partial completion to the left of punctuation characters: r:|[-+./_]=* means that wherever the string to complete contains one of the characters -+./_, a matching completion can have anything (anything matching *, which matches everything) to the left of this punctuation character. For example, qq-tcpTab completes to anything matching qq*-tcp* (the final * is from regular suffix completion).

zstyle ':completion:*' matcher-list '' 'r:|[-+./_]=*'

You can activate this through the interactive basic customization interface compinstall, under “Matching control”, as “partial-word completion”.

This is exactly what I'm looking for, thanks! I have further questions, but I'll put those in a new question. — Nick K9, Mar 17 '20 at 18:35

score 0 · Answer 2 · answered Mar 16 '20 at 13:21

In your ~/.zshrc, you can declare aliases which will be taken in account for the completion

alias qq-tcpdump-enum-dns='qq-enum-dns-tcpdump'
alias qq-tcpdump-enum-smb='qq-enum-smb-tcpdump'
alias qq-tcpdump-enum-ftp='qq-enum-ftp-tcpdump'

(Then you can source ~/.zshrc in already open terminals to get the aliases available.)

Completing command name itself in zsh

2 Answers2