bash_completionsV2.go

  1// Copyright 2013-2023 The Cobra Authors
  2//
  3// Licensed under the Apache License, Version 2.0 (the "License");
  4// you may not use this file except in compliance with the License.
  5// You may obtain a copy of the License at
  6//
  7//      http://www.apache.org/licenses/LICENSE-2.0
  8//
  9// Unless required by applicable law or agreed to in writing, software
 10// distributed under the License is distributed on an "AS IS" BASIS,
 11// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 12// See the License for the specific language governing permissions and
 13// limitations under the License.
 14
 15package cobra
 16
 17import (
 18	"bytes"
 19	"fmt"
 20	"io"
 21	"os"
 22)
 23
 24func (c *Command) genBashCompletion(w io.Writer, includeDesc bool) error {
 25	buf := new(bytes.Buffer)
 26	genBashComp(buf, c.Name(), includeDesc)
 27	_, err := buf.WriteTo(w)
 28	return err
 29}
 30
 31func genBashComp(buf io.StringWriter, name string, includeDesc bool) {
 32	compCmd := ShellCompRequestCmd
 33	if !includeDesc {
 34		compCmd = ShellCompNoDescRequestCmd
 35	}
 36
 37	WriteStringAndCheck(buf, fmt.Sprintf(`# bash completion V2 for %-36[1]s -*- shell-script -*-
 38
 39__%[1]s_debug()
 40{
 41    if [[ -n ${BASH_COMP_DEBUG_FILE-} ]]; then
 42        echo "$*" >> "${BASH_COMP_DEBUG_FILE}"
 43    fi
 44}
 45
 46# Macs have bash3 for which the bash-completion package doesn't include
 47# _init_completion. This is a minimal version of that function.
 48__%[1]s_init_completion()
 49{
 50    COMPREPLY=()
 51    _get_comp_words_by_ref "$@" cur prev words cword
 52}
 53
 54# This function calls the %[1]s program to obtain the completion
 55# results and the directive.  It fills the 'out' and 'directive' vars.
 56__%[1]s_get_completion_results() {
 57    local requestComp lastParam lastChar args
 58
 59    # Prepare the command to request completions for the program.
 60    # Calling ${words[0]} instead of directly %[1]s allows handling aliases
 61    args=("${words[@]:1}")
 62    requestComp="${words[0]} %[2]s ${args[*]}"
 63
 64    lastParam=${words[$((${#words[@]}-1))]}
 65    lastChar=${lastParam:$((${#lastParam}-1)):1}
 66    __%[1]s_debug "lastParam ${lastParam}, lastChar ${lastChar}"
 67
 68    if [[ -z ${cur} && ${lastChar} != = ]]; then
 69        # If the last parameter is complete (there is a space following it)
 70        # We add an extra empty parameter so we can indicate this to the go method.
 71        __%[1]s_debug "Adding extra empty parameter"
 72        requestComp="${requestComp} ''"
 73    fi
 74
 75    # When completing a flag with an = (e.g., %[1]s -n=<TAB>)
 76    # bash focuses on the part after the =, so we need to remove
 77    # the flag part from $cur
 78    if [[ ${cur} == -*=* ]]; then
 79        cur="${cur#*=}"
 80    fi
 81
 82    __%[1]s_debug "Calling ${requestComp}"
 83    # Use eval to handle any environment variables and such
 84    out=$(eval "${requestComp}" 2>/dev/null)
 85
 86    # Extract the directive integer at the very end of the output following a colon (:)
 87    directive=${out##*:}
 88    # Remove the directive
 89    out=${out%%:*}
 90    if [[ ${directive} == "${out}" ]]; then
 91        # There is not directive specified
 92        directive=0
 93    fi
 94    __%[1]s_debug "The completion directive is: ${directive}"
 95    __%[1]s_debug "The completions are: ${out}"
 96}
 97
 98__%[1]s_process_completion_results() {
 99    local shellCompDirectiveError=%[3]d
100    local shellCompDirectiveNoSpace=%[4]d
101    local shellCompDirectiveNoFileComp=%[5]d
102    local shellCompDirectiveFilterFileExt=%[6]d
103    local shellCompDirectiveFilterDirs=%[7]d
104    local shellCompDirectiveKeepOrder=%[8]d
105
106    if (((directive & shellCompDirectiveError) != 0)); then
107        # Error code.  No completion.
108        __%[1]s_debug "Received error from custom completion go code"
109        return
110    else
111        if (((directive & shellCompDirectiveNoSpace) != 0)); then
112            if [[ $(type -t compopt) == builtin ]]; then
113                __%[1]s_debug "Activating no space"
114                compopt -o nospace
115            else
116                __%[1]s_debug "No space directive not supported in this version of bash"
117            fi
118        fi
119        if (((directive & shellCompDirectiveKeepOrder) != 0)); then
120            if [[ $(type -t compopt) == builtin ]]; then
121                # no sort isn't supported for bash less than < 4.4
122                if [[ ${BASH_VERSINFO[0]} -lt 4 || ( ${BASH_VERSINFO[0]} -eq 4 && ${BASH_VERSINFO[1]} -lt 4 ) ]]; then
123                    __%[1]s_debug "No sort directive not supported in this version of bash"
124                else
125                    __%[1]s_debug "Activating keep order"
126                    compopt -o nosort
127                fi
128            else
129                __%[1]s_debug "No sort directive not supported in this version of bash"
130            fi
131        fi
132        if (((directive & shellCompDirectiveNoFileComp) != 0)); then
133            if [[ $(type -t compopt) == builtin ]]; then
134                __%[1]s_debug "Activating no file completion"
135                compopt +o default
136            else
137                __%[1]s_debug "No file completion directive not supported in this version of bash"
138            fi
139        fi
140    fi
141
142    # Separate activeHelp from normal completions
143    local completions=()
144    local activeHelp=()
145    __%[1]s_extract_activeHelp
146
147    if (((directive & shellCompDirectiveFilterFileExt) != 0)); then
148        # File extension filtering
149        local fullFilter="" filter filteringCmd
150
151        # Do not use quotes around the $completions variable or else newline
152        # characters will be kept.
153        for filter in ${completions[*]}; do
154            fullFilter+="$filter|"
155        done
156
157        filteringCmd="_filedir $fullFilter"
158        __%[1]s_debug "File filtering command: $filteringCmd"
159        $filteringCmd
160    elif (((directive & shellCompDirectiveFilterDirs) != 0)); then
161        # File completion for directories only
162
163        local subdir
164        subdir=${completions[0]}
165        if [[ -n $subdir ]]; then
166            __%[1]s_debug "Listing directories in $subdir"
167            pushd "$subdir" >/dev/null 2>&1 && _filedir -d && popd >/dev/null 2>&1 || return
168        else
169            __%[1]s_debug "Listing directories in ."
170            _filedir -d
171        fi
172    else
173        __%[1]s_handle_completion_types
174    fi
175
176    __%[1]s_handle_special_char "$cur" :
177    __%[1]s_handle_special_char "$cur" =
178
179    # Print the activeHelp statements before we finish
180    __%[1]s_handle_activeHelp
181}
182
183__%[1]s_handle_activeHelp() {
184    # Print the activeHelp statements
185    if ((${#activeHelp[*]} != 0)); then
186        if [ -z $COMP_TYPE ]; then
187            # Bash v3 does not set the COMP_TYPE variable.
188            printf "\n";
189            printf "%%s\n" "${activeHelp[@]}"
190            printf "\n"
191            __%[1]s_reprint_commandLine
192            return
193        fi
194
195        # Only print ActiveHelp on the second TAB press
196        if [ $COMP_TYPE -eq 63 ]; then
197            printf "\n"
198            printf "%%s\n" "${activeHelp[@]}"
199
200            if ((${#COMPREPLY[*]} == 0)); then
201                # When there are no completion choices from the program, file completion
202                # may kick in if the program has not disabled it; in such a case, we want
203                # to know if any files will match what the user typed, so that we know if
204                # there will be completions presented, so that we know how to handle ActiveHelp.
205                # To find out, we actually trigger the file completion ourselves;
206                # the call to _filedir will fill COMPREPLY if files match.
207                if (((directive & shellCompDirectiveNoFileComp) == 0)); then
208                    __%[1]s_debug "Listing files"
209                    _filedir
210                fi
211            fi
212
213            if ((${#COMPREPLY[*]} != 0)); then
214                # If there are completion choices to be shown, print a delimiter.
215                # Re-printing the command-line will automatically be done
216                # by the shell when it prints the completion choices.
217                printf -- "--"
218            else
219                # When there are no completion choices at all, we need
220                # to re-print the command-line since the shell will
221                # not be doing it itself.
222                __%[1]s_reprint_commandLine
223            fi
224        elif [ $COMP_TYPE -eq 37 ] || [ $COMP_TYPE -eq 42 ]; then
225            # For completion type: menu-complete/menu-complete-backward and insert-completions
226            # the completions are immediately inserted into the command-line, so we first
227            # print the activeHelp message and reprint the command-line since the shell won't.
228            printf "\n"
229            printf "%%s\n" "${activeHelp[@]}"
230
231            __%[1]s_reprint_commandLine
232        fi
233    fi
234}
235
236__%[1]s_reprint_commandLine() {
237    # The prompt format is only available from bash 4.4.
238    # We test if it is available before using it.
239    if (x=${PS1@P}) 2> /dev/null; then
240        printf "%%s" "${PS1@P}${COMP_LINE[@]}"
241    else
242        # Can't print the prompt.  Just print the
243        # text the user had typed, it is workable enough.
244        printf "%%s" "${COMP_LINE[@]}"
245    fi
246}
247
248# Separate activeHelp lines from real completions.
249# Fills the $activeHelp and $completions arrays.
250__%[1]s_extract_activeHelp() {
251    local activeHelpMarker="%[9]s"
252    local endIndex=${#activeHelpMarker}
253
254    while IFS='' read -r comp; do
255        [[ -z $comp ]] && continue
256
257        if [[ ${comp:0:endIndex} == $activeHelpMarker ]]; then
258            comp=${comp:endIndex}
259            __%[1]s_debug "ActiveHelp found: $comp"
260            if [[ -n $comp ]]; then
261                activeHelp+=("$comp")
262            fi
263        else
264            # Not an activeHelp line but a normal completion
265            completions+=("$comp")
266        fi
267    done <<<"${out}"
268}
269
270__%[1]s_handle_completion_types() {
271    __%[1]s_debug "__%[1]s_handle_completion_types: COMP_TYPE is $COMP_TYPE"
272
273    case $COMP_TYPE in
274    37|42)
275        # Type: menu-complete/menu-complete-backward and insert-completions
276        # If the user requested inserting one completion at a time, or all
277        # completions at once on the command-line we must remove the descriptions.
278        # https://github.com/spf13/cobra/issues/1508
279
280        # If there are no completions, we don't need to do anything
281        (( ${#completions[@]} == 0 )) && return 0
282
283        local tab=$'\t'
284
285        # Strip any description and escape the completion to handled special characters
286        IFS=$'\n' read -ra completions -d '' < <(printf "%%q\n" "${completions[@]%%%%$tab*}")
287
288        # Only consider the completions that match
289        IFS=$'\n' read -ra COMPREPLY -d '' < <(IFS=$'\n'; compgen -W "${completions[*]}" -- "${cur}")
290
291        # compgen looses the escaping so we need to escape all completions again since they will
292        # all be inserted on the command-line.
293        IFS=$'\n' read -ra COMPREPLY -d '' < <(printf "%%q\n" "${COMPREPLY[@]}")
294        ;;
295
296    *)
297        # Type: complete (normal completion)
298        __%[1]s_handle_standard_completion_case
299        ;;
300    esac
301}
302
303__%[1]s_handle_standard_completion_case() {
304    local tab=$'\t'
305
306    # If there are no completions, we don't need to do anything
307    (( ${#completions[@]} == 0 )) && return 0
308
309    # Short circuit to optimize if we don't have descriptions
310    if [[ "${completions[*]}" != *$tab* ]]; then
311        # First, escape the completions to handle special characters
312        IFS=$'\n' read -ra completions -d '' < <(printf "%%q\n" "${completions[@]}")
313        # Only consider the completions that match what the user typed
314        IFS=$'\n' read -ra COMPREPLY -d '' < <(IFS=$'\n'; compgen -W "${completions[*]}" -- "${cur}")
315
316        # compgen looses the escaping so, if there is only a single completion, we need to
317        # escape it again because it will be inserted on the command-line.  If there are multiple
318        # completions, we don't want to escape them because they will be printed in a list
319        # and we don't want to show escape characters in that list.
320        if (( ${#COMPREPLY[@]} == 1 )); then
321            COMPREPLY[0]=$(printf "%%q" "${COMPREPLY[0]}")
322        fi
323        return 0
324    fi
325
326    local longest=0
327    local compline
328    # Look for the longest completion so that we can format things nicely
329    while IFS='' read -r compline; do
330        [[ -z $compline ]] && continue
331
332        # Before checking if the completion matches what the user typed,
333        # we need to strip any description and escape the completion to handle special
334        # characters because those escape characters are part of what the user typed.
335        # Don't call "printf" in a sub-shell because it will be much slower
336        # since we are in a loop.
337        printf -v comp "%%q" "${compline%%%%$tab*}" &>/dev/null || comp=$(printf "%%q" "${compline%%%%$tab*}")
338
339        # Only consider the completions that match
340        [[ $comp == "$cur"* ]] || continue
341
342        # The completions matches.  Add it to the list of full completions including
343        # its description.  We don't escape the completion because it may get printed
344        # in a list if there are more than one and we don't want show escape characters
345        # in that list.
346        COMPREPLY+=("$compline")
347
348        # Strip any description before checking the length, and again, don't escape
349        # the completion because this length is only used when printing the completions
350        # in a list and we don't want show escape characters in that list.
351        comp=${compline%%%%$tab*}
352        if ((${#comp}>longest)); then
353            longest=${#comp}
354        fi
355    done < <(printf "%%s\n" "${completions[@]}")
356
357    # If there is a single completion left, remove the description text and escape any special characters
358    if ((${#COMPREPLY[*]} == 1)); then
359        __%[1]s_debug "COMPREPLY[0]: ${COMPREPLY[0]}"
360        COMPREPLY[0]=$(printf "%%q" "${COMPREPLY[0]%%%%$tab*}")
361        __%[1]s_debug "Removed description from single completion, which is now: ${COMPREPLY[0]}"
362    else
363        # Format the descriptions
364        __%[1]s_format_comp_descriptions $longest
365    fi
366}
367
368__%[1]s_handle_special_char()
369{
370    local comp="$1"
371    local char=$2
372    if [[ "$comp" == *${char}* && "$COMP_WORDBREAKS" == *${char}* ]]; then
373        local word=${comp%%"${comp##*${char}}"}
374        local idx=${#COMPREPLY[*]}
375        while ((--idx >= 0)); do
376            COMPREPLY[idx]=${COMPREPLY[idx]#"$word"}
377        done
378    fi
379}
380
381__%[1]s_format_comp_descriptions()
382{
383    local tab=$'\t'
384    local comp desc maxdesclength
385    local longest=$1
386
387    local i ci
388    for ci in ${!COMPREPLY[*]}; do
389        comp=${COMPREPLY[ci]}
390        # Properly format the description string which follows a tab character if there is one
391        if [[ "$comp" == *$tab* ]]; then
392            __%[1]s_debug "Original comp: $comp"
393            desc=${comp#*$tab}
394            comp=${comp%%%%$tab*}
395
396            # $COLUMNS stores the current shell width.
397            # Remove an extra 4 because we add 2 spaces and 2 parentheses.
398            maxdesclength=$(( COLUMNS - longest - 4 ))
399
400            # Make sure we can fit a description of at least 8 characters
401            # if we are to align the descriptions.
402            if ((maxdesclength > 8)); then
403                # Add the proper number of spaces to align the descriptions
404                for ((i = ${#comp} ; i < longest ; i++)); do
405                    comp+=" "
406                done
407            else
408                # Don't pad the descriptions so we can fit more text after the completion
409                maxdesclength=$(( COLUMNS - ${#comp} - 4 ))
410            fi
411
412            # If there is enough space for any description text,
413            # truncate the descriptions that are too long for the shell width
414            if ((maxdesclength > 0)); then
415                if ((${#desc} > maxdesclength)); then
416                    desc=${desc:0:$(( maxdesclength - 1 ))}
417                    desc+="…"
418                fi
419                comp+="  ($desc)"
420            fi
421            COMPREPLY[ci]=$comp
422            __%[1]s_debug "Final comp: $comp"
423        fi
424    done
425}
426
427__start_%[1]s()
428{
429    local cur prev words cword split
430
431    COMPREPLY=()
432
433    # Call _init_completion from the bash-completion package
434    # to prepare the arguments properly
435    if declare -F _init_completion >/dev/null 2>&1; then
436        _init_completion -n =: || return
437    else
438        __%[1]s_init_completion -n =: || return
439    fi
440
441    __%[1]s_debug
442    __%[1]s_debug "========= starting completion logic =========="
443    __%[1]s_debug "cur is ${cur}, words[*] is ${words[*]}, #words[@] is ${#words[@]}, cword is $cword"
444
445    # The user could have moved the cursor backwards on the command-line.
446    # We need to trigger completion from the $cword location, so we need
447    # to truncate the command-line ($words) up to the $cword location.
448    words=("${words[@]:0:$cword+1}")
449    __%[1]s_debug "Truncated words[*]: ${words[*]},"
450
451    local out directive
452    __%[1]s_get_completion_results
453    __%[1]s_process_completion_results
454}
455
456if [[ $(type -t compopt) = "builtin" ]]; then
457    complete -o default -F __start_%[1]s %[1]s
458else
459    complete -o default -o nospace -F __start_%[1]s %[1]s
460fi
461
462# ex: ts=4 sw=4 et filetype=sh
463`, name, compCmd,
464		ShellCompDirectiveError, ShellCompDirectiveNoSpace, ShellCompDirectiveNoFileComp,
465		ShellCompDirectiveFilterFileExt, ShellCompDirectiveFilterDirs, ShellCompDirectiveKeepOrder,
466		activeHelpMarker))
467}
468
469// GenBashCompletionFileV2 generates Bash completion version 2.
470func (c *Command) GenBashCompletionFileV2(filename string, includeDesc bool) error {
471	outFile, err := os.Create(filename)
472	if err != nil {
473		return err
474	}
475	defer outFile.Close()
476
477	return c.GenBashCompletionV2(outFile, includeDesc)
478}
479
480// GenBashCompletionV2 generates Bash completion file version 2
481// and writes it to the passed writer.
482func (c *Command) GenBashCompletionV2(w io.Writer, includeDesc bool) error {
483	return c.genBashCompletion(w, includeDesc)
484}