cobra/bash_completionsV2.go
Ville Skyttä 9e88759b19
perf(bash-v2): speed up filtering menu-complete descriptions (#1692)
Similarly as fb8031162c (+ the empty entry
fix) did for the "regular", non-menu completion cases.
2022-05-04 16:23:02 -04:00

328 lines
11 KiB
Go

package cobra
import (
"bytes"
"fmt"
"io"
"os"
)
func (c *Command) genBashCompletion(w io.Writer, includeDesc bool) error {
buf := new(bytes.Buffer)
genBashComp(buf, c.Name(), includeDesc)
_, err := buf.WriteTo(w)
return err
}
func genBashComp(buf io.StringWriter, name string, includeDesc bool) {
compCmd := ShellCompRequestCmd
if !includeDesc {
compCmd = ShellCompNoDescRequestCmd
}
WriteStringAndCheck(buf, fmt.Sprintf(`# bash completion V2 for %-36[1]s -*- shell-script -*-
__%[1]s_debug()
{
if [[ -n ${BASH_COMP_DEBUG_FILE:-} ]]; then
echo "$*" >> "${BASH_COMP_DEBUG_FILE}"
fi
}
# Macs have bash3 for which the bash-completion package doesn't include
# _init_completion. This is a minimal version of that function.
__%[1]s_init_completion()
{
COMPREPLY=()
_get_comp_words_by_ref "$@" cur prev words cword
}
# This function calls the %[1]s program to obtain the completion
# results and the directive. It fills the 'out' and 'directive' vars.
__%[1]s_get_completion_results() {
local requestComp lastParam lastChar args
# Prepare the command to request completions for the program.
# Calling ${words[0]} instead of directly %[1]s allows to handle aliases
args=("${words[@]:1}")
requestComp="${words[0]} %[2]s ${args[*]}"
lastParam=${words[$((${#words[@]}-1))]}
lastChar=${lastParam:$((${#lastParam}-1)):1}
__%[1]s_debug "lastParam ${lastParam}, lastChar ${lastChar}"
if [ -z "${cur}" ] && [ "${lastChar}" != "=" ]; then
# If the last parameter is complete (there is a space following it)
# We add an extra empty parameter so we can indicate this to the go method.
__%[1]s_debug "Adding extra empty parameter"
requestComp="${requestComp} ''"
fi
# When completing a flag with an = (e.g., %[1]s -n=<TAB>)
# bash focuses on the part after the =, so we need to remove
# the flag part from $cur
if [[ "${cur}" == -*=* ]]; then
cur="${cur#*=}"
fi
__%[1]s_debug "Calling ${requestComp}"
# Use eval to handle any environment variables and such
out=$(eval "${requestComp}" 2>/dev/null)
# Extract the directive integer at the very end of the output following a colon (:)
directive=${out##*:}
# Remove the directive
out=${out%%:*}
if [ "${directive}" = "${out}" ]; then
# There is not directive specified
directive=0
fi
__%[1]s_debug "The completion directive is: ${directive}"
__%[1]s_debug "The completions are: ${out}"
}
__%[1]s_process_completion_results() {
local shellCompDirectiveError=%[3]d
local shellCompDirectiveNoSpace=%[4]d
local shellCompDirectiveNoFileComp=%[5]d
local shellCompDirectiveFilterFileExt=%[6]d
local shellCompDirectiveFilterDirs=%[7]d
if [ $((directive & shellCompDirectiveError)) -ne 0 ]; then
# Error code. No completion.
__%[1]s_debug "Received error from custom completion go code"
return
else
if [ $((directive & shellCompDirectiveNoSpace)) -ne 0 ]; then
if [[ $(type -t compopt) = "builtin" ]]; then
__%[1]s_debug "Activating no space"
compopt -o nospace
else
__%[1]s_debug "No space directive not supported in this version of bash"
fi
fi
if [ $((directive & shellCompDirectiveNoFileComp)) -ne 0 ]; then
if [[ $(type -t compopt) = "builtin" ]]; then
__%[1]s_debug "Activating no file completion"
compopt +o default
else
__%[1]s_debug "No file completion directive not supported in this version of bash"
fi
fi
fi
if [ $((directive & shellCompDirectiveFilterFileExt)) -ne 0 ]; then
# File extension filtering
local fullFilter filter filteringCmd
# Do not use quotes around the $out variable or else newline
# characters will be kept.
for filter in ${out}; do
fullFilter+="$filter|"
done
filteringCmd="_filedir $fullFilter"
__%[1]s_debug "File filtering command: $filteringCmd"
$filteringCmd
elif [ $((directive & shellCompDirectiveFilterDirs)) -ne 0 ]; then
# File completion for directories only
# Use printf to strip any trailing newline
local subdir
subdir=$(printf "%%s" "${out}")
if [ -n "$subdir" ]; then
__%[1]s_debug "Listing directories in $subdir"
pushd "$subdir" >/dev/null 2>&1 && _filedir -d && popd >/dev/null 2>&1 || return
else
__%[1]s_debug "Listing directories in ."
_filedir -d
fi
else
__%[1]s_handle_completion_types
fi
__%[1]s_handle_special_char "$cur" :
__%[1]s_handle_special_char "$cur" =
}
__%[1]s_handle_completion_types() {
__%[1]s_debug "__%[1]s_handle_completion_types: COMP_TYPE is $COMP_TYPE"
case $COMP_TYPE in
37|42)
# Type: menu-complete/menu-complete-backward and insert-completions
# If the user requested inserting one completion at a time, or all
# completions at once on the command-line we must remove the descriptions.
# https://github.com/spf13/cobra/issues/1508
local tab=$'\t' comp
while IFS='' read -r comp; do
[[ -z $comp ]] && continue
# Strip any description
comp=${comp%%%%$tab*}
# Only consider the completions that match
if [[ $comp == "$cur"* ]]; then
COMPREPLY+=("$comp")
fi
done < <(printf "%%s\n" "${out}")
;;
*)
# Type: complete (normal completion)
__%[1]s_handle_standard_completion_case
;;
esac
}
__%[1]s_handle_standard_completion_case() {
local tab=$'\t' comp
# Short circuit to optimize if we don't have descriptions
if [[ $out != *$tab* ]]; then
while IFS='' read -r comp; do
COMPREPLY+=("$comp")
done < <(IFS=$'\n' compgen -W "$out" -- "$cur")
return 0
fi
local longest=0
local compline
# Look for the longest completion so that we can format things nicely
while IFS='' read -r compline; do
# Strip any description before checking the length
comp=${compline%%%%$tab*}
# Only consider the completions that match
[[ $comp == "$cur"* ]] || continue
COMPREPLY+=("$compline")
if ((${#comp}>longest)); then
longest=${#comp}
fi
done < <(printf "%%s\n" "${out}")
# If there is a single completion left, remove the description text
if [ ${#COMPREPLY[*]} -eq 1 ]; then
__%[1]s_debug "COMPREPLY[0]: ${COMPREPLY[0]}"
comp="${COMPREPLY[0]%%%%$tab*}"
__%[1]s_debug "Removed description from single completion, which is now: ${comp}"
COMPREPLY[0]=$comp
else # Format the descriptions
__%[1]s_format_comp_descriptions $longest
fi
}
__%[1]s_handle_special_char()
{
local comp="$1"
local char=$2
if [[ "$comp" == *${char}* && "$COMP_WORDBREAKS" == *${char}* ]]; then
local word=${comp%%"${comp##*${char}}"}
local idx=${#COMPREPLY[*]}
while [[ $((--idx)) -ge 0 ]]; do
COMPREPLY[$idx]=${COMPREPLY[$idx]#"$word"}
done
fi
}
__%[1]s_format_comp_descriptions()
{
local tab=$'\t'
local comp desc maxdesclength
local longest=$1
local i ci
for ci in ${!COMPREPLY[*]}; do
comp=${COMPREPLY[ci]}
# Properly format the description string which follows a tab character if there is one
if [[ "$comp" == *$tab* ]]; then
__%[1]s_debug "Original comp: $comp"
desc=${comp#*$tab}
comp=${comp%%%%$tab*}
# $COLUMNS stores the current shell width.
# Remove an extra 4 because we add 2 spaces and 2 parentheses.
maxdesclength=$(( COLUMNS - longest - 4 ))
# Make sure we can fit a description of at least 8 characters
# if we are to align the descriptions.
if [[ $maxdesclength -gt 8 ]]; then
# Add the proper number of spaces to align the descriptions
for ((i = ${#comp} ; i < longest ; i++)); do
comp+=" "
done
else
# Don't pad the descriptions so we can fit more text after the completion
maxdesclength=$(( COLUMNS - ${#comp} - 4 ))
fi
# If there is enough space for any description text,
# truncate the descriptions that are too long for the shell width
if [ $maxdesclength -gt 0 ]; then
if [ ${#desc} -gt $maxdesclength ]; then
desc=${desc:0:$(( maxdesclength - 1 ))}
desc+="…"
fi
comp+=" ($desc)"
fi
COMPREPLY[ci]=$comp
__%[1]s_debug "Final comp: $comp"
fi
done
}
__start_%[1]s()
{
local cur prev words cword split
COMPREPLY=()
# Call _init_completion from the bash-completion package
# to prepare the arguments properly
if declare -F _init_completion >/dev/null 2>&1; then
_init_completion -n "=:" || return
else
__%[1]s_init_completion -n "=:" || return
fi
__%[1]s_debug
__%[1]s_debug "========= starting completion logic =========="
__%[1]s_debug "cur is ${cur}, words[*] is ${words[*]}, #words[@] is ${#words[@]}, cword is $cword"
# The user could have moved the cursor backwards on the command-line.
# We need to trigger completion from the $cword location, so we need
# to truncate the command-line ($words) up to the $cword location.
words=("${words[@]:0:$cword+1}")
__%[1]s_debug "Truncated words[*]: ${words[*]},"
local out directive
__%[1]s_get_completion_results
__%[1]s_process_completion_results
}
if [[ $(type -t compopt) = "builtin" ]]; then
complete -o default -F __start_%[1]s %[1]s
else
complete -o default -o nospace -F __start_%[1]s %[1]s
fi
# ex: ts=4 sw=4 et filetype=sh
`, name, compCmd,
ShellCompDirectiveError, ShellCompDirectiveNoSpace, ShellCompDirectiveNoFileComp,
ShellCompDirectiveFilterFileExt, ShellCompDirectiveFilterDirs))
}
// GenBashCompletionFileV2 generates Bash completion version 2.
func (c *Command) GenBashCompletionFileV2(filename string, includeDesc bool) error {
outFile, err := os.Create(filename)
if err != nil {
return err
}
defer outFile.Close()
return c.GenBashCompletionV2(outFile, includeDesc)
}
// GenBashCompletionV2 generates Bash completion file version 2
// and writes it to the passed writer.
func (c *Command) GenBashCompletionV2(w io.Writer, includeDesc bool) error {
return c.genBashCompletion(w, includeDesc)
}