bash-it/plugins/available/alias-completion.plugin.bash

105 lines
4.5 KiB
Bash

# shellcheck shell=bash
about-plugin 'Automatic completion of aliases'
# Load after the other completions to understand what needs to be completed
# BASH_IT_LOAD_PRIORITY: 800
# References:
# http://superuser.com/a/437508/119764
# http://stackoverflow.com/a/1793178/1228454
# Automatically add completion for all aliases to commands having completion functions
function alias_completion() {
local namespace="alias_completion"
local tmp_file completion_loader alias_name alias_tokens line completions
local alias_arg_words new_completion compl_func compl_wrapper alias_defn
# parse function based completion definitions, where capture group 2 => function and 3 => trigger
local compl_regex='complete( +[^ ]+)* -F ([^ ]+) ("[^"]+"|[^ ]+)'
# parse alias definitions, where capture group 1 => trigger, 2 => command, 3 => command arguments
local alias_regex="alias( -- | )([^=]+)='(\"[^\"]+\"|[^ ]+)(( +[^ ]+)*)'"
# create array of function completion triggers, keeping multi-word triggers together
IFS=$'\n' read -d '' -ra completions < <(complete -p)
((${#completions[@]} == 0)) && return 0
completions=("${completions[@]##complete -* * -}") # strip all but last option plus trigger(s)
completions=("${completions[@]#complete -}") # strip last option and arg, leaving only trigger(s)
completions=("${completions[@]#? * }") # strip last option and arg, leaving only trigger(s)
# create temporary file for wrapper functions and completions
tmp_file="$(mktemp -t "${namespace}-${RANDOM}XXXXXX")" || return 1
completion_loader="$(complete -p -D 2> /dev/null | sed -Ene 's/.* -F ([^ ]*).*/\1/p')"
# read in "<alias> '<aliased command>' '<command args>'" lines from defined aliases
# some aliases do have backslashes that needs to be interpreted
# shellcheck disable=SC2162
while read line; do
line="${line#alias }"
alias_name="${line%%=*}"
alias_defn="${line#*=}" # alias definition
alias_cmd="${alias_defn%%[[:space:]]*}" # first word of alias
alias_cmd="${alias_cmd:1}" # lose opening quotation mark
alias_args="${alias_defn#*[[:space:]]}" # everything after first word
alias_args="${alias_args:0:-1}" # lose ending quotation mark
# skip aliases to pipes, boolean control structures and other command lists
[[ "${alias_args}" =~ [\|\&\;\)\(\n] ]] && continue
# avoid expanding wildcards
read -a alias_arg_words <<< "$alias_args"
# skip alias if there is no completion function triggered by the aliased command
if ! _bash-it-array-contains-element "$alias_cmd" "${completions[@]}"; then
if [[ -n "$completion_loader" ]]; then
# force loading of completions for the aliased command
"${completion_loader:?}" "${alias_cmd}"
# 124 means completion loader was successful
[[ $? -eq 124 ]] || continue
completions+=("$alias_cmd")
else
continue
fi
fi
new_completion="$(complete -p "$alias_cmd" 2> /dev/null)"
# create a wrapper inserting the alias arguments if any
if [[ -n $alias_args ]]; then
compl_func="${new_completion/#* -F /}"
compl_func="${compl_func%% *}"
# avoid recursive call loops by ignoring our own functions
if [[ "${compl_func#_"$namespace"::}" == "$compl_func" ]]; then
compl_wrapper="_${namespace}::${alias_name}"
echo "function $compl_wrapper {
local compl_word=\$2
local prec_word=\$3
# check if prec_word is the alias itself. if so, replace it
# with the last word in the unaliased form, i.e.,
# alias_cmd + ' ' + alias_args.
if [[ \$COMP_LINE == \"\$prec_word \$compl_word\" ]]; then
prec_word='$alias_cmd $alias_args'
prec_word=\${prec_word#* }
fi
(( COMP_CWORD += ${#alias_arg_words[@]} ))
COMP_WORDS=($alias_cmd $alias_args \${COMP_WORDS[@]:1})
(( COMP_POINT -= \${#COMP_LINE} ))
COMP_LINE=\${COMP_LINE/$alias_name/$alias_cmd $alias_args}
(( COMP_POINT += \${#COMP_LINE} ))
$compl_func \"$alias_cmd\" \"\$compl_word\" \"\$prec_word\"
}" >> "$tmp_file"
new_completion="${new_completion/ -F $compl_func / -F $compl_wrapper }"
fi
fi
# replace completion trigger by alias
if [[ -n $new_completion ]]; then
new_completion="${new_completion% *} $alias_name"
echo "$new_completion" >> "$tmp_file"
fi
done < <(alias -p)
# shellcheck source=/dev/null
source "$tmp_file" && command rm -f "$tmp_file"
}
alias_completion