cobra/fish_completions.go
Marc Khouzam 06e4b59b20
Allow fish comp to support trailing empty lines (#1284)
Some programs may output extra empty lines after the directive.
Those lines must be ignored for fish shell completion to work.
zsh and bash are not impacted.

Signed-off-by: Marc Khouzam <marc.khouzam@montreal.ca>
Co-authored-by: Johannes Altmanninger <aclopte@gmail.com>

Co-authored-by: Johannes Altmanninger <aclopte@gmail.com>
2021-05-03 10:23:34 -06:00

221 lines
7.8 KiB
Go

package cobra
import (
"bytes"
"fmt"
"io"
"os"
"strings"
)
func genFishComp(buf io.StringWriter, name string, includeDesc bool) {
// Variables should not contain a '-' or ':' character
nameForVar := name
nameForVar = strings.Replace(nameForVar, "-", "_", -1)
nameForVar = strings.Replace(nameForVar, ":", "_", -1)
compCmd := ShellCompRequestCmd
if !includeDesc {
compCmd = ShellCompNoDescRequestCmd
}
WriteStringAndCheck(buf, fmt.Sprintf("# fish completion for %-36s -*- shell-script -*-\n", name))
WriteStringAndCheck(buf, fmt.Sprintf(`
function __%[1]s_debug
set file "$BASH_COMP_DEBUG_FILE"
if test -n "$file"
echo "$argv" >> $file
end
end
function __%[1]s_perform_completion
__%[1]s_debug "Starting __%[1]s_perform_completion with: $argv"
set args (string split -- " " "$argv")
set lastArg "$args[-1]"
__%[1]s_debug "args: $args"
__%[1]s_debug "last arg: $lastArg"
set emptyArg ""
if test -z "$lastArg"
__%[1]s_debug "Setting emptyArg"
set emptyArg \"\"
end
__%[1]s_debug "emptyArg: $emptyArg"
if not type -q "$args[1]"
# This can happen when "complete --do-complete %[2]s" is called when running this script.
__%[1]s_debug "Cannot find $args[1]. No completions."
return
end
set requestComp "$args[1] %[3]s $args[2..-1] $emptyArg"
__%[1]s_debug "Calling $requestComp"
set results (eval $requestComp 2> /dev/null)
# Some programs may output extra empty lines after the directive.
# Let's ignore them or else it will break completion.
# Ref: https://github.com/spf13/cobra/issues/1279
for line in $results[-1..1]
if test (string trim -- $line) = ""
# Found an empty line, remove it
set results $results[1..-2]
else
# Found non-empty line, we have our proper output
break
end
end
set comps $results[1..-2]
set directiveLine $results[-1]
# For Fish, when completing a flag with an = (e.g., <program> -n=<TAB>)
# completions must be prefixed with the flag
set flagPrefix (string match -r -- '-.*=' "$lastArg")
__%[1]s_debug "Comps: $comps"
__%[1]s_debug "DirectiveLine: $directiveLine"
__%[1]s_debug "flagPrefix: $flagPrefix"
for comp in $comps
printf "%%s%%s\n" "$flagPrefix" "$comp"
end
printf "%%s\n" "$directiveLine"
end
# This function does three things:
# 1- Obtain the completions and store them in the global __%[1]s_comp_results
# 2- Set the __%[1]s_comp_do_file_comp flag if file completion should be performed
# and unset it otherwise
# 3- Return true if the completion results are not empty
function __%[1]s_prepare_completions
# Start fresh
set --erase __%[1]s_comp_do_file_comp
set --erase __%[1]s_comp_results
# Check if the command-line is already provided. This is useful for testing.
if not set --query __%[1]s_comp_commandLine
# Use the -c flag to allow for completion in the middle of the line
set __%[1]s_comp_commandLine (commandline -c)
end
__%[1]s_debug "commandLine is: $__%[1]s_comp_commandLine"
set results (__%[1]s_perform_completion "$__%[1]s_comp_commandLine")
set --erase __%[1]s_comp_commandLine
__%[1]s_debug "Completion results: $results"
if test -z "$results"
__%[1]s_debug "No completion, probably due to a failure"
# Might as well do file completion, in case it helps
set --global __%[1]s_comp_do_file_comp 1
return 1
end
set directive (string sub --start 2 $results[-1])
set --global __%[1]s_comp_results $results[1..-2]
__%[1]s_debug "Completions are: $__%[1]s_comp_results"
__%[1]s_debug "Directive is: $directive"
set shellCompDirectiveError %[4]d
set shellCompDirectiveNoSpace %[5]d
set shellCompDirectiveNoFileComp %[6]d
set shellCompDirectiveFilterFileExt %[7]d
set shellCompDirectiveFilterDirs %[8]d
if test -z "$directive"
set directive 0
end
set compErr (math (math --scale 0 $directive / $shellCompDirectiveError) %% 2)
if test $compErr -eq 1
__%[1]s_debug "Received error directive: aborting."
# Might as well do file completion, in case it helps
set --global __%[1]s_comp_do_file_comp 1
return 1
end
set filefilter (math (math --scale 0 $directive / $shellCompDirectiveFilterFileExt) %% 2)
set dirfilter (math (math --scale 0 $directive / $shellCompDirectiveFilterDirs) %% 2)
if test $filefilter -eq 1; or test $dirfilter -eq 1
__%[1]s_debug "File extension filtering or directory filtering not supported"
# Do full file completion instead
set --global __%[1]s_comp_do_file_comp 1
return 1
end
set nospace (math (math --scale 0 $directive / $shellCompDirectiveNoSpace) %% 2)
set nofiles (math (math --scale 0 $directive / $shellCompDirectiveNoFileComp) %% 2)
__%[1]s_debug "nospace: $nospace, nofiles: $nofiles"
# Important not to quote the variable for count to work
set numComps (count $__%[1]s_comp_results)
__%[1]s_debug "numComps: $numComps"
if test $numComps -eq 1; and test $nospace -ne 0
# To support the "nospace" directive we trick the shell
# by outputting an extra, longer completion.
__%[1]s_debug "Adding second completion to perform nospace directive"
set --append __%[1]s_comp_results $__%[1]s_comp_results[1].
end
if test $numComps -eq 0; and test $nofiles -eq 0
__%[1]s_debug "Requesting file completion"
set --global __%[1]s_comp_do_file_comp 1
end
# If we don't want file completion, we must return true even if there
# are no completions found. This is because fish will perform the last
# completion command, even if its condition is false, if no other
# completion command was triggered
return (not set --query __%[1]s_comp_do_file_comp)
end
# Since Fish completions are only loaded once the user triggers them, we trigger them ourselves
# so we can properly delete any completions provided by another script.
# The space after the the program name is essential to trigger completion for the program
# and not completion of the program name itself.
complete --do-complete "%[2]s " > /dev/null 2>&1
# Using '> /dev/null 2>&1' since '&>' is not supported in older versions of fish.
# Remove any pre-existing completions for the program since we will be handling all of them.
complete -c %[2]s -e
# The order in which the below two lines are defined is very important so that __%[1]s_prepare_completions
# is called first. It is __%[1]s_prepare_completions that sets up the __%[1]s_comp_do_file_comp variable.
#
# This completion will be run second as complete commands are added FILO.
# It triggers file completion choices when __%[1]s_comp_do_file_comp is set.
complete -c %[2]s -n 'set --query __%[1]s_comp_do_file_comp'
# This completion will be run first as complete commands are added FILO.
# The call to __%[1]s_prepare_completions will setup both __%[1]s_comp_results and __%[1]s_comp_do_file_comp.
# It provides the program's completion choices.
complete -c %[2]s -n '__%[1]s_prepare_completions' -f -a '$__%[1]s_comp_results'
`, nameForVar, name, compCmd,
ShellCompDirectiveError, ShellCompDirectiveNoSpace, ShellCompDirectiveNoFileComp,
ShellCompDirectiveFilterFileExt, ShellCompDirectiveFilterDirs))
}
// GenFishCompletion generates fish completion file and writes to the passed writer.
func (c *Command) GenFishCompletion(w io.Writer, includeDesc bool) error {
buf := new(bytes.Buffer)
genFishComp(buf, c.Name(), includeDesc)
_, err := buf.WriteTo(w)
return err
}
// GenFishCompletionFile generates fish completion file.
func (c *Command) GenFishCompletionFile(filename string, includeDesc bool) error {
outFile, err := os.Create(filename)
if err != nil {
return err
}
defer outFile.Close()
return c.GenFishCompletion(outFile, includeDesc)
}