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// Copyright 2013-2023 The Cobra Authors
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//
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// Licensed under the Apache License, Version 2.0 (the "License");
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// you may not use this file except in compliance with the License.
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// You may obtain a copy of the License at
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//
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//      http://www.apache.org/licenses/LICENSE-2.0
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//
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// Unless required by applicable law or agreed to in writing, software
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// distributed under the License is distributed on an "AS IS" BASIS,
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// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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// See the License for the specific language governing permissions and
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// limitations under the License.
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package cobra
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17
import (
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	"bytes"
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	"fmt"
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	"io"
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	"os"
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	"sort"
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	"strings"
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25
	"github.com/spf13/pflag"
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)
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// Annotations for Bash completion.
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const (
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	BashCompFilenameExt     = "cobra_annotation_bash_completion_filename_extensions"
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	BashCompCustom          = "cobra_annotation_bash_completion_custom"
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	BashCompOneRequiredFlag = "cobra_annotation_bash_completion_one_required_flag"
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	BashCompSubdirsInDir    = "cobra_annotation_bash_completion_subdirs_in_dir"
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)
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func writePreamble(buf io.StringWriter, name string) {
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	WriteStringAndCheck(buf, fmt.Sprintf("# bash completion for %-36s -*- shell-script -*-\n", name))
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	WriteStringAndCheck(buf, fmt.Sprintf(`
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__%[1]s_debug()
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{
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    if [[ -n ${BASH_COMP_DEBUG_FILE:-} ]]; then
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        echo "$*" >> "${BASH_COMP_DEBUG_FILE}"
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    fi
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}
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46
# Homebrew on Macs have version 1.3 of bash-completion which doesn't include
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# _init_completion. This is a very minimal version of that function.
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__%[1]s_init_completion()
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{
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    COMPREPLY=()
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    _get_comp_words_by_ref "$@" cur prev words cword
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}
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54
__%[1]s_index_of_word()
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{
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    local w word=$1
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    shift
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    index=0
59
    for w in "$@"; do
60
        [[ $w = "$word" ]] && return
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        index=$((index+1))
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    done
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    index=-1
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}
65

66
__%[1]s_contains_word()
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{
68
    local w word=$1; shift
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    for w in "$@"; do
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        [[ $w = "$word" ]] && return
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    done
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    return 1
73
}
74

75
__%[1]s_handle_go_custom_completion()
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{
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    __%[1]s_debug "${FUNCNAME[0]}: cur is ${cur}, words[*] is ${words[*]}, #words[@] is ${#words[@]}"
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79
    local shellCompDirectiveError=%[3]d
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    local shellCompDirectiveNoSpace=%[4]d
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    local shellCompDirectiveNoFileComp=%[5]d
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    local shellCompDirectiveFilterFileExt=%[6]d
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    local shellCompDirectiveFilterDirs=%[7]d
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85
    local out requestComp lastParam lastChar comp directive args
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87
    # Prepare the command to request completions for the program.
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    # Calling ${words[0]} instead of directly %[1]s allows handling aliases
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    args=("${words[@]:1}")
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    # Disable ActiveHelp which is not supported for bash completion v1
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    requestComp="%[8]s=0 ${words[0]} %[2]s ${args[*]}"
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93
    lastParam=${words[$((${#words[@]}-1))]}
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    lastChar=${lastParam:$((${#lastParam}-1)):1}
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    __%[1]s_debug "${FUNCNAME[0]}: lastParam ${lastParam}, lastChar ${lastChar}"
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97
    if [ -z "${cur}" ] && [ "${lastChar}" != "=" ]; then
98
        # If the last parameter is complete (there is a space following it)
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        # We add an extra empty parameter so we can indicate this to the go method.
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        __%[1]s_debug "${FUNCNAME[0]}: Adding extra empty parameter"
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        requestComp="${requestComp} \"\""
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    fi
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104
    __%[1]s_debug "${FUNCNAME[0]}: calling ${requestComp}"
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    # Use eval to handle any environment variables and such
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    out=$(eval "${requestComp}" 2>/dev/null)
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108
    # Extract the directive integer at the very end of the output following a colon (:)
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    directive=${out##*:}
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    # Remove the directive
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    out=${out%%:*}
112
    if [ "${directive}" = "${out}" ]; then
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        # There is not directive specified
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        directive=0
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    fi
116
    __%[1]s_debug "${FUNCNAME[0]}: the completion directive is: ${directive}"
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    __%[1]s_debug "${FUNCNAME[0]}: the completions are: ${out}"
118

119
    if [ $((directive & shellCompDirectiveError)) -ne 0 ]; then
120
        # Error code.  No completion.
121
        __%[1]s_debug "${FUNCNAME[0]}: received error from custom completion go code"
122
        return
123
    else
124
        if [ $((directive & shellCompDirectiveNoSpace)) -ne 0 ]; then
125
            if [[ $(type -t compopt) = "builtin" ]]; then
126
                __%[1]s_debug "${FUNCNAME[0]}: activating no space"
127
                compopt -o nospace
128
            fi
129
        fi
130
        if [ $((directive & shellCompDirectiveNoFileComp)) -ne 0 ]; then
131
            if [[ $(type -t compopt) = "builtin" ]]; then
132
                __%[1]s_debug "${FUNCNAME[0]}: activating no file completion"
133
                compopt +o default
134
            fi
135
        fi
136
    fi
137

138
    if [ $((directive & shellCompDirectiveFilterFileExt)) -ne 0 ]; then
139
        # File extension filtering
140
        local fullFilter filter filteringCmd
141
        # Do not use quotes around the $out variable or else newline
142
        # characters will be kept.
143
        for filter in ${out}; do
144
            fullFilter+="$filter|"
145
        done
146

147
        filteringCmd="_filedir $fullFilter"
148
        __%[1]s_debug "File filtering command: $filteringCmd"
149
        $filteringCmd
150
    elif [ $((directive & shellCompDirectiveFilterDirs)) -ne 0 ]; then
151
        # File completion for directories only
152
        local subdir
153
        # Use printf to strip any trailing newline
154
        subdir=$(printf "%%s" "${out}")
155
        if [ -n "$subdir" ]; then
156
            __%[1]s_debug "Listing directories in $subdir"
157
            __%[1]s_handle_subdirs_in_dir_flag "$subdir"
158
        else
159
            __%[1]s_debug "Listing directories in ."
160
            _filedir -d
161
        fi
162
    else
163
        while IFS='' read -r comp; do
164
            COMPREPLY+=("$comp")
165
        done < <(compgen -W "${out}" -- "$cur")
166
    fi
167
}
168

169
__%[1]s_handle_reply()
170
{
171
    __%[1]s_debug "${FUNCNAME[0]}"
172
    local comp
173
    case $cur in
174
        -*)
175
            if [[ $(type -t compopt) = "builtin" ]]; then
176
                compopt -o nospace
177
            fi
178
            local allflags
179
            if [ ${#must_have_one_flag[@]} -ne 0 ]; then
180
                allflags=("${must_have_one_flag[@]}")
181
            else
182
                allflags=("${flags[*]} ${two_word_flags[*]}")
183
            fi
184
            while IFS='' read -r comp; do
185
                COMPREPLY+=("$comp")
186
            done < <(compgen -W "${allflags[*]}" -- "$cur")
187
            if [[ $(type -t compopt) = "builtin" ]]; then
188
                [[ "${COMPREPLY[0]}" == *= ]] || compopt +o nospace
189
            fi
190

191
            # complete after --flag=abc
192
            if [[ $cur == *=* ]]; then
193
                if [[ $(type -t compopt) = "builtin" ]]; then
194
                    compopt +o nospace
195
                fi
196

197
                local index flag
198
                flag="${cur%%=*}"
199
                __%[1]s_index_of_word "${flag}" "${flags_with_completion[@]}"
200
                COMPREPLY=()
201
                if [[ ${index} -ge 0 ]]; then
202
                    PREFIX=""
203
                    cur="${cur#*=}"
204
                    ${flags_completion[${index}]}
205
                    if [ -n "${ZSH_VERSION:-}" ]; then
206
                        # zsh completion needs --flag= prefix
207
                        eval "COMPREPLY=( \"\${COMPREPLY[@]/#/${flag}=}\" )"
208
                    fi
209
                fi
210
            fi
211

212
            if [[ -z "${flag_parsing_disabled}" ]]; then
213
                # If flag parsing is enabled, we have completed the flags and can return.
214
                # If flag parsing is disabled, we may not know all (or any) of the flags, so we fallthrough
215
                # to possibly call handle_go_custom_completion.
216
                return 0;
217
            fi
218
            ;;
219
    esac
220

221
    # check if we are handling a flag with special work handling
222
    local index
223
    __%[1]s_index_of_word "${prev}" "${flags_with_completion[@]}"
224
    if [[ ${index} -ge 0 ]]; then
225
        ${flags_completion[${index}]}
226
        return
227
    fi
228

229
    # we are parsing a flag and don't have a special handler, no completion
230
    if [[ ${cur} != "${words[cword]}" ]]; then
231
        return
232
    fi
233

234
    local completions
235
    completions=("${commands[@]}")
236
    if [[ ${#must_have_one_noun[@]} -ne 0 ]]; then
237
        completions+=("${must_have_one_noun[@]}")
238
    elif [[ -n "${has_completion_function}" ]]; then
239
        # if a go completion function is provided, defer to that function
240
        __%[1]s_handle_go_custom_completion
241
    fi
242
    if [[ ${#must_have_one_flag[@]} -ne 0 ]]; then
243
        completions+=("${must_have_one_flag[@]}")
244
    fi
245
    while IFS='' read -r comp; do
246
        COMPREPLY+=("$comp")
247
    done < <(compgen -W "${completions[*]}" -- "$cur")
248

249
    if [[ ${#COMPREPLY[@]} -eq 0 && ${#noun_aliases[@]} -gt 0 && ${#must_have_one_noun[@]} -ne 0 ]]; then
250
        while IFS='' read -r comp; do
251
            COMPREPLY+=("$comp")
252
        done < <(compgen -W "${noun_aliases[*]}" -- "$cur")
253
    fi
254

255
    if [[ ${#COMPREPLY[@]} -eq 0 ]]; then
256
        if declare -F __%[1]s_custom_func >/dev/null; then
257
            # try command name qualified custom func
258
            __%[1]s_custom_func
259
        else
260
            # otherwise fall back to unqualified for compatibility
261
            declare -F __custom_func >/dev/null && __custom_func
262
        fi
263
    fi
264

265
    # available in bash-completion >= 2, not always present on macOS
266
    if declare -F __ltrim_colon_completions >/dev/null; then
267
        __ltrim_colon_completions "$cur"
268
    fi
269

270
    # If there is only 1 completion and it is a flag with an = it will be completed
271
    # but we don't want a space after the =
272
    if [[ "${#COMPREPLY[@]}" -eq "1" ]] && [[ $(type -t compopt) = "builtin" ]] && [[ "${COMPREPLY[0]}" == --*= ]]; then
273
       compopt -o nospace
274
    fi
275
}
276

277
# The arguments should be in the form "ext1|ext2|extn"
278
__%[1]s_handle_filename_extension_flag()
279
{
280
    local ext="$1"
281
    _filedir "@(${ext})"
282
}
283

284
__%[1]s_handle_subdirs_in_dir_flag()
285
{
286
    local dir="$1"
287
    pushd "${dir}" >/dev/null 2>&1 && _filedir -d && popd >/dev/null 2>&1 || return
288
}
289

290
__%[1]s_handle_flag()
291
{
292
    __%[1]s_debug "${FUNCNAME[0]}: c is $c words[c] is ${words[c]}"
293

294
    # if a command required a flag, and we found it, unset must_have_one_flag()
295
    local flagname=${words[c]}
296
    local flagvalue=""
297
    # if the word contained an =
298
    if [[ ${words[c]} == *"="* ]]; then
299
        flagvalue=${flagname#*=} # take in as flagvalue after the =
300
        flagname=${flagname%%=*} # strip everything after the =
301
        flagname="${flagname}=" # but put the = back
302
    fi
303
    __%[1]s_debug "${FUNCNAME[0]}: looking for ${flagname}"
304
    if __%[1]s_contains_word "${flagname}" "${must_have_one_flag[@]}"; then
305
        must_have_one_flag=()
306
    fi
307

308
    # if you set a flag which only applies to this command, don't show subcommands
309
    if __%[1]s_contains_word "${flagname}" "${local_nonpersistent_flags[@]}"; then
310
      commands=()
311
    fi
312

313
    # keep flag value with flagname as flaghash
314
    # flaghash variable is an associative array which is only supported in bash > 3.
315
    if [[ -z "${BASH_VERSION:-}" || "${BASH_VERSINFO[0]:-}" -gt 3 ]]; then
316
        if [ -n "${flagvalue}" ] ; then
317
            flaghash[${flagname}]=${flagvalue}
318
        elif [ -n "${words[ $((c+1)) ]}" ] ; then
319
            flaghash[${flagname}]=${words[ $((c+1)) ]}
320
        else
321
            flaghash[${flagname}]="true" # pad "true" for bool flag
322
        fi
323
    fi
324

325
    # skip the argument to a two word flag
326
    if [[ ${words[c]} != *"="* ]] && __%[1]s_contains_word "${words[c]}" "${two_word_flags[@]}"; then
327
        __%[1]s_debug "${FUNCNAME[0]}: found a flag ${words[c]}, skip the next argument"
328
        c=$((c+1))
329
        # if we are looking for a flags value, don't show commands
330
        if [[ $c -eq $cword ]]; then
331
            commands=()
332
        fi
333
    fi
334

335
    c=$((c+1))
336

337
}
338

339
__%[1]s_handle_noun()
340
{
341
    __%[1]s_debug "${FUNCNAME[0]}: c is $c words[c] is ${words[c]}"
342

343
    if __%[1]s_contains_word "${words[c]}" "${must_have_one_noun[@]}"; then
344
        must_have_one_noun=()
345
    elif __%[1]s_contains_word "${words[c]}" "${noun_aliases[@]}"; then
346
        must_have_one_noun=()
347
    fi
348

349
    nouns+=("${words[c]}")
350
    c=$((c+1))
351
}
352

353
__%[1]s_handle_command()
354
{
355
    __%[1]s_debug "${FUNCNAME[0]}: c is $c words[c] is ${words[c]}"
356

357
    local next_command
358
    if [[ -n ${last_command} ]]; then
359
        next_command="_${last_command}_${words[c]//:/__}"
360
    else
361
        if [[ $c -eq 0 ]]; then
362
            next_command="_%[1]s_root_command"
363
        else
364
            next_command="_${words[c]//:/__}"
365
        fi
366
    fi
367
    c=$((c+1))
368
    __%[1]s_debug "${FUNCNAME[0]}: looking for ${next_command}"
369
    declare -F "$next_command" >/dev/null && $next_command
370
}
371

372
__%[1]s_handle_word()
373
{
374
    if [[ $c -ge $cword ]]; then
375
        __%[1]s_handle_reply
376
        return
377
    fi
378
    __%[1]s_debug "${FUNCNAME[0]}: c is $c words[c] is ${words[c]}"
379
    if [[ "${words[c]}" == -* ]]; then
380
        __%[1]s_handle_flag
381
    elif __%[1]s_contains_word "${words[c]}" "${commands[@]}"; then
382
        __%[1]s_handle_command
383
    elif [[ $c -eq 0 ]]; then
384
        __%[1]s_handle_command
385
    elif __%[1]s_contains_word "${words[c]}" "${command_aliases[@]}"; then
386
        # aliashash variable is an associative array which is only supported in bash > 3.
387
        if [[ -z "${BASH_VERSION:-}" || "${BASH_VERSINFO[0]:-}" -gt 3 ]]; then
388
            words[c]=${aliashash[${words[c]}]}
389
            __%[1]s_handle_command
390
        else
391
            __%[1]s_handle_noun
392
        fi
393
    else
394
        __%[1]s_handle_noun
395
    fi
396
    __%[1]s_handle_word
397
}
398

399
`, name, ShellCompNoDescRequestCmd,
400
		ShellCompDirectiveError, ShellCompDirectiveNoSpace, ShellCompDirectiveNoFileComp,
401
		ShellCompDirectiveFilterFileExt, ShellCompDirectiveFilterDirs, activeHelpEnvVar(name)))
402
}
403

404
func writePostscript(buf io.StringWriter, name string) {
405
	name = strings.ReplaceAll(name, ":", "__")
406
	WriteStringAndCheck(buf, fmt.Sprintf("__start_%s()\n", name))
407
	WriteStringAndCheck(buf, fmt.Sprintf(`{
408
    local cur prev words cword split
409
    declare -A flaghash 2>/dev/null || :
410
    declare -A aliashash 2>/dev/null || :
411
    if declare -F _init_completion >/dev/null 2>&1; then
412
        _init_completion -s || return
413
    else
414
        __%[1]s_init_completion -n "=" || return
415
    fi
416

417
    local c=0
418
    local flag_parsing_disabled=
419
    local flags=()
420
    local two_word_flags=()
421
    local local_nonpersistent_flags=()
422
    local flags_with_completion=()
423
    local flags_completion=()
424
    local commands=("%[1]s")
425
    local command_aliases=()
426
    local must_have_one_flag=()
427
    local must_have_one_noun=()
428
    local has_completion_function=""
429
    local last_command=""
430
    local nouns=()
431
    local noun_aliases=()
432

433
    __%[1]s_handle_word
434
}
435

436
`, name))
437
	WriteStringAndCheck(buf, fmt.Sprintf(`if [[ $(type -t compopt) = "builtin" ]]; then
438
    complete -o default -F __start_%s %s
439
else
440
    complete -o default -o nospace -F __start_%s %s
441
fi
442

443
`, name, name, name, name))
444
	WriteStringAndCheck(buf, "# ex: ts=4 sw=4 et filetype=sh\n")
445
}
446

447
func writeCommands(buf io.StringWriter, cmd *Command) {
448
	WriteStringAndCheck(buf, "    commands=()\n")
449
	for _, c := range cmd.Commands() {
450
		if !c.IsAvailableCommand() && c != cmd.helpCommand {
451
			continue
452
		}
453
		WriteStringAndCheck(buf, fmt.Sprintf("    commands+=(%q)\n", c.Name()))
454
		writeCmdAliases(buf, c)
455
	}
456
	WriteStringAndCheck(buf, "\n")
457
}
458

459
func writeFlagHandler(buf io.StringWriter, name string, annotations map[string][]string, cmd *Command) {
460
	for key, value := range annotations {
461
		switch key {
462
		case BashCompFilenameExt:
463
			WriteStringAndCheck(buf, fmt.Sprintf("    flags_with_completion+=(%q)\n", name))
464

465
			var ext string
466
			if len(value) > 0 {
467
				ext = fmt.Sprintf("__%s_handle_filename_extension_flag ", cmd.Root().Name()) + strings.Join(value, "|")
468
			} else {
469
				ext = "_filedir"
470
			}
471
			WriteStringAndCheck(buf, fmt.Sprintf("    flags_completion+=(%q)\n", ext))
472
		case BashCompCustom:
473
			WriteStringAndCheck(buf, fmt.Sprintf("    flags_with_completion+=(%q)\n", name))
474

475
			if len(value) > 0 {
476
				handlers := strings.Join(value, "; ")
477
				WriteStringAndCheck(buf, fmt.Sprintf("    flags_completion+=(%q)\n", handlers))
478
			} else {
479
				WriteStringAndCheck(buf, "    flags_completion+=(:)\n")
480
			}
481
		case BashCompSubdirsInDir:
482
			WriteStringAndCheck(buf, fmt.Sprintf("    flags_with_completion+=(%q)\n", name))
483

484
			var ext string
485
			if len(value) == 1 {
486
				ext = fmt.Sprintf("__%s_handle_subdirs_in_dir_flag ", cmd.Root().Name()) + value[0]
487
			} else {
488
				ext = "_filedir -d"
489
			}
490
			WriteStringAndCheck(buf, fmt.Sprintf("    flags_completion+=(%q)\n", ext))
491
		}
492
	}
493
}
494

495
const cbn = "\")\n"
496

497
func writeShortFlag(buf io.StringWriter, flag *pflag.Flag, cmd *Command) {
498
	name := flag.Shorthand
499
	format := "    "
500
	if len(flag.NoOptDefVal) == 0 {
501
		format += "two_word_"
502
	}
503
	format += "flags+=(\"-%s" + cbn
504
	WriteStringAndCheck(buf, fmt.Sprintf(format, name))
505
	writeFlagHandler(buf, "-"+name, flag.Annotations, cmd)
506
}
507

508
func writeFlag(buf io.StringWriter, flag *pflag.Flag, cmd *Command) {
509
	name := flag.Name
510
	format := "    flags+=(\"--%s"
511
	if len(flag.NoOptDefVal) == 0 {
512
		format += "="
513
	}
514
	format += cbn
515
	WriteStringAndCheck(buf, fmt.Sprintf(format, name))
516
	if len(flag.NoOptDefVal) == 0 {
517
		format = "    two_word_flags+=(\"--%s" + cbn
518
		WriteStringAndCheck(buf, fmt.Sprintf(format, name))
519
	}
520
	writeFlagHandler(buf, "--"+name, flag.Annotations, cmd)
521
}
522

523
func writeLocalNonPersistentFlag(buf io.StringWriter, flag *pflag.Flag) {
524
	name := flag.Name
525
	format := "    local_nonpersistent_flags+=(\"--%[1]s" + cbn
526
	if len(flag.NoOptDefVal) == 0 {
527
		format += "    local_nonpersistent_flags+=(\"--%[1]s=" + cbn
528
	}
529
	WriteStringAndCheck(buf, fmt.Sprintf(format, name))
530
	if len(flag.Shorthand) > 0 {
531
		WriteStringAndCheck(buf, fmt.Sprintf("    local_nonpersistent_flags+=(\"-%s\")\n", flag.Shorthand))
532
	}
533
}
534

535
// prepareCustomAnnotationsForFlags setup annotations for go completions for registered flags
536
func prepareCustomAnnotationsForFlags(cmd *Command) {
537
	flagCompletionMutex.RLock()
538
	defer flagCompletionMutex.RUnlock()
539
	for flag := range flagCompletionFunctions {
540
		// Make sure the completion script calls the __*_go_custom_completion function for
541
		// every registered flag.  We need to do this here (and not when the flag was registered
542
		// for completion) so that we can know the root command name for the prefix
543
		// of __<prefix>_go_custom_completion
544
		if flag.Annotations == nil {
545
			flag.Annotations = map[string][]string{}
546
		}
547
		flag.Annotations[BashCompCustom] = []string{fmt.Sprintf("__%[1]s_handle_go_custom_completion", cmd.Root().Name())}
548
	}
549
}
550

551
func writeFlags(buf io.StringWriter, cmd *Command) {
552
	prepareCustomAnnotationsForFlags(cmd)
553
	WriteStringAndCheck(buf, `    flags=()
554
    two_word_flags=()
555
    local_nonpersistent_flags=()
556
    flags_with_completion=()
557
    flags_completion=()
558

559
`)
560

561
	if cmd.DisableFlagParsing {
562
		WriteStringAndCheck(buf, "    flag_parsing_disabled=1\n")
563
	}
564

565
	localNonPersistentFlags := cmd.LocalNonPersistentFlags()
566
	cmd.NonInheritedFlags().VisitAll(func(flag *pflag.Flag) {
567
		if nonCompletableFlag(flag) {
568
			return
569
		}
570
		writeFlag(buf, flag, cmd)
571
		if len(flag.Shorthand) > 0 {
572
			writeShortFlag(buf, flag, cmd)
573
		}
574
		// localNonPersistentFlags are used to stop the completion of subcommands when one is set
575
		// if TraverseChildren is true we should allow to complete subcommands
576
		if localNonPersistentFlags.Lookup(flag.Name) != nil && !cmd.Root().TraverseChildren {
577
			writeLocalNonPersistentFlag(buf, flag)
578
		}
579
	})
580
	cmd.InheritedFlags().VisitAll(func(flag *pflag.Flag) {
581
		if nonCompletableFlag(flag) {
582
			return
583
		}
584
		writeFlag(buf, flag, cmd)
585
		if len(flag.Shorthand) > 0 {
586
			writeShortFlag(buf, flag, cmd)
587
		}
588
	})
589

590
	WriteStringAndCheck(buf, "\n")
591
}
592

593
func writeRequiredFlag(buf io.StringWriter, cmd *Command) {
594
	WriteStringAndCheck(buf, "    must_have_one_flag=()\n")
595
	flags := cmd.NonInheritedFlags()
596
	flags.VisitAll(func(flag *pflag.Flag) {
597
		if nonCompletableFlag(flag) {
598
			return
599
		}
600
		if _, ok := flag.Annotations[BashCompOneRequiredFlag]; ok {
601
			format := "    must_have_one_flag+=(\"--%s"
602
			if flag.Value.Type() != "bool" {
603
				format += "="
604
			}
605
			format += cbn
606
			WriteStringAndCheck(buf, fmt.Sprintf(format, flag.Name))
607

608
			if len(flag.Shorthand) > 0 {
609
				WriteStringAndCheck(buf, fmt.Sprintf("    must_have_one_flag+=(\"-%s"+cbn, flag.Shorthand))
610
			}
611
		}
612
	})
613
}
614

615
func writeRequiredNouns(buf io.StringWriter, cmd *Command) {
616
	WriteStringAndCheck(buf, "    must_have_one_noun=()\n")
617
	sort.Strings(cmd.ValidArgs)
618
	for _, value := range cmd.ValidArgs {
619
		// Remove any description that may be included following a tab character.
620
		// Descriptions are not supported by bash completion.
621
		value = strings.SplitN(value, "\t", 2)[0]
622
		WriteStringAndCheck(buf, fmt.Sprintf("    must_have_one_noun+=(%q)\n", value))
623
	}
624
	if cmd.ValidArgsFunction != nil {
625
		WriteStringAndCheck(buf, "    has_completion_function=1\n")
626
	}
627
}
628

629
func writeCmdAliases(buf io.StringWriter, cmd *Command) {
630
	if len(cmd.Aliases) == 0 {
631
		return
632
	}
633

634
	sort.Strings(cmd.Aliases)
635

636
	WriteStringAndCheck(buf, fmt.Sprint(`    if [[ -z "${BASH_VERSION:-}" || "${BASH_VERSINFO[0]:-}" -gt 3 ]]; then`, "\n"))
637
	for _, value := range cmd.Aliases {
638
		WriteStringAndCheck(buf, fmt.Sprintf("        command_aliases+=(%q)\n", value))
639
		WriteStringAndCheck(buf, fmt.Sprintf("        aliashash[%q]=%q\n", value, cmd.Name()))
640
	}
641
	WriteStringAndCheck(buf, `    fi`)
642
	WriteStringAndCheck(buf, "\n")
643
}
644
func writeArgAliases(buf io.StringWriter, cmd *Command) {
645
	WriteStringAndCheck(buf, "    noun_aliases=()\n")
646
	sort.Strings(cmd.ArgAliases)
647
	for _, value := range cmd.ArgAliases {
648
		WriteStringAndCheck(buf, fmt.Sprintf("    noun_aliases+=(%q)\n", value))
649
	}
650
}
651

652
func gen(buf io.StringWriter, cmd *Command) {
653
	for _, c := range cmd.Commands() {
654
		if !c.IsAvailableCommand() && c != cmd.helpCommand {
655
			continue
656
		}
657
		gen(buf, c)
658
	}
659
	commandName := cmd.CommandPath()
660
	commandName = strings.ReplaceAll(commandName, " ", "_")
661
	commandName = strings.ReplaceAll(commandName, ":", "__")
662

663
	if cmd.Root() == cmd {
664
		WriteStringAndCheck(buf, fmt.Sprintf("_%s_root_command()\n{\n", commandName))
665
	} else {
666
		WriteStringAndCheck(buf, fmt.Sprintf("_%s()\n{\n", commandName))
667
	}
668

669
	WriteStringAndCheck(buf, fmt.Sprintf("    last_command=%q\n", commandName))
670
	WriteStringAndCheck(buf, "\n")
671
	WriteStringAndCheck(buf, "    command_aliases=()\n")
672
	WriteStringAndCheck(buf, "\n")
673

674
	writeCommands(buf, cmd)
675
	writeFlags(buf, cmd)
676
	writeRequiredFlag(buf, cmd)
677
	writeRequiredNouns(buf, cmd)
678
	writeArgAliases(buf, cmd)
679
	WriteStringAndCheck(buf, "}\n\n")
680
}
681

682
// GenBashCompletion generates bash completion file and writes to the passed writer.
683
func (c *Command) GenBashCompletion(w io.Writer) error {
684
	buf := new(bytes.Buffer)
685
	writePreamble(buf, c.Name())
686
	if len(c.BashCompletionFunction) > 0 {
687
		buf.WriteString(c.BashCompletionFunction + "\n")
688
	}
689
	gen(buf, c)
690
	writePostscript(buf, c.Name())
691

692
	_, err := buf.WriteTo(w)
693
	return err
694
}
695

696
func nonCompletableFlag(flag *pflag.Flag) bool {
697
	return flag.Hidden || len(flag.Deprecated) > 0
698
}
699

700
// GenBashCompletionFile generates bash completion file.
701
func (c *Command) GenBashCompletionFile(filename string) error {
702
	outFile, err := os.Create(filename)
703
	if err != nil {
704
		return err
705
	}
706
	defer outFile.Close()
707

708
	return c.GenBashCompletion(outFile)
709
}
710

711