Bash completion V2 with completion descriptions (#1146)
* Bash completion v2 This v2 version of bash completion is based on Go completions. It also supports descriptions like the other shells. Signed-off-by: Marc Khouzam <marc.khouzam@montreal.ca> * Only consider matching completions for formatting Signed-off-by: Marc Khouzam <marc.khouzam@montreal.ca> * Use bash compV2 for the default completion command Signed-off-by: Marc Khouzam <marc.khouzam@montreal.ca> * Update comments that still referred to bash completion Signed-off-by: Marc Khouzam <marc.khouzam@montreal.ca>
This commit is contained in:
Marc Khouzam
GitHub
parent
d0f318d45b
commit
b36196066e
@ -6,6 +6,8 @@ Please refer to [Shell Completions](shell_completions.md) for details.
|
||||
|
||||
For backward compatibility, Cobra still supports its legacy dynamic completion solution (described below). Unlike the `ValidArgsFunction` solution, the legacy solution will only work for Bash shell-completion and not for other shells. This legacy solution can be used along-side `ValidArgsFunction` and `RegisterFlagCompletionFunc()`, as long as both solutions are not used for the same command. This provides a path to gradually migrate from the legacy solution to the new solution.
|
||||
|
||||
**Note**: Cobra's default `completion` command uses bash completion V2. If you are currently using Cobra's legacy dynamic completion solution, you should not use the default `completion` command but continue using your own.
|
||||
|
||||
The legacy solution allows you to inject bash functions into the bash completion script. Those bash functions are responsible for providing the completion choices for your own completions.
|
||||
|
||||
Some code that works in kubernetes:
|
||||
|
||||
302
bash_completionsV2.go
Normal file
302
bash_completionsV2.go
Normal file
@ -0,0 +1,302 @@
|
||||
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" "${out[0]}")
|
||||
if [ -n "$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
|
||||
__%[1]s_handle_standard_completion_case
|
||||
fi
|
||||
|
||||
__%[1]s_handle_special_char "$cur" :
|
||||
__%[1]s_handle_special_char "$cur" =
|
||||
}
|
||||
|
||||
__%[1]s_handle_standard_completion_case() {
|
||||
local tab comp
|
||||
tab=$(printf '\t')
|
||||
|
||||
local longest=0
|
||||
# Look for the longest completion so that we can format things nicely
|
||||
while IFS='' read -r comp; do
|
||||
# Strip any description before checking the length
|
||||
comp=${comp%%%%$tab*}
|
||||
# Only consider the completions that match
|
||||
comp=$(compgen -W "$comp" -- "$cur")
|
||||
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" "${out[@]}")
|
||||
|
||||
while IFS='' read -r comp; do
|
||||
COMPREPLY+=("$comp")
|
||||
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
|
||||
}
|
||||
|
||||
__%[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]#"$word"}
|
||||
done
|
||||
fi
|
||||
}
|
||||
|
||||
__%[1]s_format_comp_descriptions()
|
||||
{
|
||||
local tab
|
||||
tab=$(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 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)
|
||||
}
|
||||
11
command.go
11
command.go
@ -63,9 +63,9 @@ type Command struct {
|
||||
// Example is examples of how to use the command.
|
||||
Example string
|
||||
|
||||
// ValidArgs is list of all valid non-flag arguments that are accepted in bash completions
|
||||
// ValidArgs is list of all valid non-flag arguments that are accepted in shell completions
|
||||
ValidArgs []string
|
||||
// ValidArgsFunction is an optional function that provides valid non-flag arguments for bash completion.
|
||||
// ValidArgsFunction is an optional function that provides valid non-flag arguments for shell completion.
|
||||
// It is a dynamic version of using ValidArgs.
|
||||
// Only one of ValidArgs and ValidArgsFunction can be used for a command.
|
||||
ValidArgsFunction func(cmd *Command, args []string, toComplete string) ([]string, ShellCompDirective)
|
||||
@ -74,11 +74,12 @@ type Command struct {
|
||||
Args PositionalArgs
|
||||
|
||||
// ArgAliases is List of aliases for ValidArgs.
|
||||
// These are not suggested to the user in the bash completion,
|
||||
// These are not suggested to the user in the shell completion,
|
||||
// but accepted if entered manually.
|
||||
ArgAliases []string
|
||||
|
||||
// BashCompletionFunction is custom functions used by the bash autocompletion generator.
|
||||
// BashCompletionFunction is custom bash functions used by the legacy bash autocompletion generator.
|
||||
// For portability with other shells, it is recommended to instead use ValidArgsFunction
|
||||
BashCompletionFunction string
|
||||
|
||||
// Deprecated defines, if this command is deprecated and should print this string when used.
|
||||
@ -938,7 +939,7 @@ func (c *Command) ExecuteC() (cmd *Command, err error) {
|
||||
args = os.Args[1:]
|
||||
}
|
||||
|
||||
// initialize the hidden command to be used for bash completion
|
||||
// initialize the hidden command to be used for shell completion
|
||||
c.initCompleteCmd(args)
|
||||
|
||||
var flags []string
|
||||
|
||||
@ -34,7 +34,6 @@ const (
|
||||
|
||||
// ShellCompDirectiveNoFileComp indicates that the shell should not provide
|
||||
// file completion even when no completion is provided.
|
||||
// This currently does not work for zsh or bash < 4
|
||||
ShellCompDirectiveNoFileComp
|
||||
|
||||
// ShellCompDirectiveFilterFileExt indicates that the provided completions
|
||||
@ -592,9 +591,12 @@ You will need to start a new shell for this setup to take effect.
|
||||
DisableFlagsInUseLine: true,
|
||||
ValidArgsFunction: NoFileCompletions,
|
||||
RunE: func(cmd *Command, args []string) error {
|
||||
return cmd.Root().GenBashCompletion(out)
|
||||
return cmd.Root().GenBashCompletionV2(out, !noDesc)
|
||||
},
|
||||
}
|
||||
if haveNoDescFlag {
|
||||
bash.Flags().BoolVar(&noDesc, compCmdNoDescFlagName, compCmdNoDescFlagDefault, compCmdNoDescFlagDesc)
|
||||
}
|
||||
|
||||
zsh := &Command{
|
||||
Use: "zsh",
|
||||
|
||||
@ -2097,9 +2097,9 @@ func TestDefaultCompletionCmd(t *testing.T) {
|
||||
removeCompCmd(rootCmd)
|
||||
|
||||
var compCmd *Command
|
||||
// Test that the --no-descriptions flag is present for the relevant shells only
|
||||
// Test that the --no-descriptions flag is present on all shells
|
||||
assertNoErr(t, rootCmd.Execute())
|
||||
for _, shell := range []string{"fish", "powershell", "zsh"} {
|
||||
for _, shell := range []string{"bash", "fish", "powershell", "zsh"} {
|
||||
if compCmd, _, err = rootCmd.Find([]string{compCmdName, shell}); err != nil {
|
||||
t.Errorf("Unexpected error: %v", err)
|
||||
}
|
||||
@ -2107,14 +2107,6 @@ func TestDefaultCompletionCmd(t *testing.T) {
|
||||
t.Errorf("Missing --%s flag for %s shell", compCmdNoDescFlagName, shell)
|
||||
}
|
||||
}
|
||||
for _, shell := range []string{"bash"} {
|
||||
if compCmd, _, err = rootCmd.Find([]string{compCmdName, shell}); err != nil {
|
||||
t.Errorf("Unexpected error: %v", err)
|
||||
}
|
||||
if flag := compCmd.Flags().Lookup(compCmdNoDescFlagName); flag != nil {
|
||||
t.Errorf("Unexpected --%s flag for %s shell", compCmdNoDescFlagName, shell)
|
||||
}
|
||||
}
|
||||
// Remove completion command for the next test
|
||||
removeCompCmd(rootCmd)
|
||||
|
||||
|
||||
@ -400,6 +400,36 @@ completion firstcommand secondcommand
|
||||
For backward compatibility, Cobra still supports its bash legacy dynamic completion solution.
|
||||
Please refer to [Bash Completions](bash_completions.md) for details.
|
||||
|
||||
### Bash completion V2
|
||||
|
||||
Cobra provides two versions for bash completion. The original bash completion (which started it all!) can be used by calling
|
||||
`GenBashCompletion()` or `GenBashCompletionFile()`.
|
||||
|
||||
A new V2 bash completion version is also available. This version can be used by calling `GenBashCompletionV2()` or
|
||||
`GenBashCompletionFileV2()`. The V2 version does **not** support the legacy dynamic completion (see [Bash Completions]
|
||||
(bash_completions.md)) but instead works only with the Go dynamic completion solution described in this Readme.
|
||||
Unless your program already uses the legacy dynamic completion solution, it is recommended that you use the bash
|
||||
completion V2 solution which provides the following extra features:
|
||||
- Supports completion descriptions (like the other shells)
|
||||
- Small completion script of less than 300 lines (v1 generates scripts of thousands of lines; `kubectl` for example has a bash v1 completion script of over 13K lines)
|
||||
- Streamlined user experience thanks to a completion behavior aligned with the other shells
|
||||
|
||||
`Bash` completion V2 supports descriptions for completions. When calling `GenBashCompletionV2()` or `GenBashCompletionFileV2()`
|
||||
you must provide these functions with a parameter indicating if the completions should be annotated with a description; Cobra
|
||||
will provide the description automatically based on usage information. You can choose to make this option configurable by
|
||||
your users.
|
||||
|
||||
```
|
||||
# With descriptions
|
||||
$ helm s[tab][tab]
|
||||
search (search for a keyword in charts) status (display the status of the named release)
|
||||
show (show information of a chart)
|
||||
|
||||
# Without descriptions
|
||||
$ helm s[tab][tab]
|
||||
search show status
|
||||
```
|
||||
**Note**: Cobra's default `completion` command uses bash completion V2. If for some reason you need to use bash completion V1, you will need to implement your own `completion` command.
|
||||
## Zsh completions
|
||||
|
||||
Cobra supports native zsh completion generated from the root `cobra.Command`.
|
||||
|
||||
Loading…
Reference in New Issue
Block a user