From d72b1258b68817649a14eda2cae04fc3fdb7f1ed Mon Sep 17 00:00:00 2001 From: Marc Khouzam Date: Sat, 16 May 2020 20:06:45 -0400 Subject: [PATCH] Bash completion v2 This v2 version of bash completion is based on Go completions. It also supports descriptions like fish and zsh. Signed-off-by: Marc Khouzam --- bash_completionsV2.go | 277 ++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 277 insertions(+) create mode 100644 bash_completionsV2.go diff --git a/bash_completionsV2.go b/bash_completionsV2.go new file mode 100644 index 000000000..6f0b25342 --- /dev/null +++ b/bash_completionsV2.go @@ -0,0 +1,277 @@ +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 *bytes.Buffer, name string, includeDesc bool) { + compCmd := ShellCompRequestCmd + if !includeDesc { + compCmd = ShellCompNoDescRequestCmd + } + + buf.WriteString(fmt.Sprintf(`# bash completion for %-36[1]s -*- shell-script -*- + +__%[1]s_debug() +{ + if [[ -n ${BASH_COMP_DEBUG_FILE} ]]; then + echo "$*" >> "${BASH_COMP_DEBUG_FILE}" + fi +} + +__%[1]s_perform_completion() +{ + __%[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 shellCompDirectiveError=%[3]d + local shellCompDirectiveNoSpace=%[4]d + local shellCompDirectiveNoFileComp=%[5]d + local shellCompDirectiveFilterFileExt=%[6]d + local shellCompDirectiveFilterDirs=%[7]d + + local out requestComp lastParam lastChar comp directive args flagPrefix + + # 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=) + # bash focuses on the part after the =, so we need to remove + # the flag part from $cur + if [[ "${cur}" == -*=* ]]; then + flagPrefix="${cur%%%%=*}=" + cur="${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[*]}" + + 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 + fi + fi + if [ $((directive & shellCompDirectiveNoFileComp)) -ne 0 ]; then + if [[ $(type -t compopt) = "builtin" ]]; then + __%[1]s_debug "Activating no file completion" + compopt +o default + 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 [ $((directive & shellCompDirectiveFilterDirs)) -ne 0 ]; then + # File completion for directories only + + # Use printf to strip any trailing newline + local subdir=$(printf "%%s" "${out[0]}") + if [ -n "$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 + local tab=$(printf '\t') + local longest=0 + # Look for the longest completion so that we can format things nicely + while IFS='' read -r comp; do + comp=${comp%%%%$tab*} + if ((${#comp}>$longest)); then + longest=${#comp} + fi + done < <(printf "%%s\n" "${out[@]}") + + local completions=() + while IFS='' read -r comp; do + if [ -z "$comp" ]; then + continue + fi + + __%[1]s_debug "Original comp: $comp" + comp="$(__%[1]s_format_comp_descriptions "$comp" $longest)" + __%[1]s_debug "Final comp: $comp" + completions+=("$comp") + done < <(printf "%%s\n" "${out[@]}") + + while IFS='' read -r comp; do + # Although this script should only be used for bash + # there may be programs that still convert the bash + # script into a zsh one. To continue supporting those + # programs, we do this single adaptation for zsh + if [ -n "${ZSH_VERSION}" ]; then + # zsh completion needs --flag= prefix + COMPREPLY+=("$flagPrefix$comp") + else + COMPREPLY+=("$comp") + fi + done < <(compgen -W "${completions[*]}" -- "$cur") + + # 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]%%%% *}" + __%[1]s_debug "Removed description from single completion, which is now: ${comp}" + COMPREPLY=() + COMPREPLY+=("$comp") + fi + fi + + __%[1]s_handle_special_char "$cur" : + __%[1]s_handle_special_char "$cur" = +} + +__%[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]#"$word"} + done + fi +} + +__%[1]s_format_comp_descriptions() +{ + local tab=$(printf '\t') + local comp="$1" + local longest=$2 + + # Properly format the description string which follows a tab character if there is one + if [[ "$comp" == *$tab* ]]; then + desc=${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 + fi + + # Must use printf to escape all special characters + printf "%%q" "${comp}" +} + +__start_%[1]s() +{ + local cur prev words cword + + COMPREPLY=() + _get_comp_words_by_ref -n "=:" cur prev words cword + + __%[1]s_perform_completion +} + +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) +}