cobra/fish_completions.go
Marc Khouzam a684a6d7f5
Fish completion using Go completion (#1048)
Signed-off-by: Marc Khouzam <marc.khouzam@montreal.ca>
2020-04-10 13:56:28 -06:00

173 lines
5.8 KiB
Go

package cobra
import (
"bytes"
"fmt"
"io"
"os"
)
func genFishComp(buf *bytes.Buffer, name string, includeDesc bool) {
compCmd := ShellCompRequestCmd
if !includeDesc {
compCmd = ShellCompNoDescRequestCmd
}
buf.WriteString(fmt.Sprintf("# fish completion for %-36s -*- shell-script -*-\n", name))
buf.WriteString(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: $emptyArg"
set requestComp "$args[1] %[2]s $args[2..-1] $emptyArg"
__%[1]s_debug "Calling $requestComp"
set results (eval $requestComp 2> /dev/null)
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
set __%[1]s_comp_commandLine (commandline)
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 0
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: $directive"
if test -z "$directive"
set directive 0
end
set compErr (math (math --scale 0 $directive / %[3]d) %% 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 0
end
set nospace (math (math --scale 0 $directive / %[4]d) %% 2)
set nofiles (math (math --scale 0 $directive / %[5]d) %% 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 $nofiles -eq 0
__%[1]s_debug "Requesting file completion"
set --global __%[1]s_comp_do_file_comp 1
end
# If we don't want file completion, we must return true even if there
# are no completions found. This is because fish will perform the last
# completion command, even if its condition is false, if no other
# completion command was triggered
return (not set --query __%[1]s_comp_do_file_comp)
end
# Remove any pre-existing completions for the program since we will be handling all of them
# TODO this cleanup is not sufficient. Fish completions are only loaded once the user triggers
# them, so the below deletion will not work as it is run too early. What else can we do?
complete -c %[1]s -e
# The order in which the below two lines are defined is very important so that __%[1]s_prepare_completions
# is called first. It is __%[1]s_prepare_completions that sets up the __%[1]s_comp_do_file_comp variable.
#
# This completion will be run second as complete commands are added FILO.
# It triggers file completion choices when __%[1]s_comp_do_file_comp is set.
complete -c %[1]s -n 'set --query __%[1]s_comp_do_file_comp'
# This completion will be run first as complete commands are added FILO.
# The call to __%[1]s_prepare_completions will setup both __%[1]s_comp_results abd __%[1]s_comp_do_file_comp.
# It provides the program's completion choices.
complete -c %[1]s -n '__%[1]s_prepare_completions' -f -a '$__%[1]s_comp_results'
`, name, compCmd, ShellCompDirectiveError, ShellCompDirectiveNoSpace, ShellCompDirectiveNoFileComp))
}
// 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)
}