Function getPluginCompletions

pkg/cmd/plugin/plugin_completion.go:224–258

getPluginCompletions receives an executable's filepath, a slice of arguments, and a slice of environment variables to relay to the executable. The executable is responsible for printing the completions of the plugin for the current set of arguments.

(executablePath string, cmdArgs, environment []string)

// The executable is responsible for printing the completions of the
// plugin for the current set of arguments.
func getPluginCompletions(executablePath string, cmdArgs, environment []string) ([]string, cobra.ShellCompDirective) {
	buf := new(bytes.Buffer)

	prog := exec.Command(executablePath, cmdArgs...)
	prog.Stdin = os.Stdin
	prog.Stdout = buf
	prog.Stderr = os.Stderr
	prog.Env = environment

	var comps []string
	directive := cobra.ShellCompDirectiveDefault
	if err := prog.Run(); err == nil {
		for _, comp := range strings.Split(buf.String(), "\n") {
			// Remove any empty lines
			if len(comp) > 0 {
				comps = append(comps, comp)
			}
		}

		// Check if the last line of output is of the form :<integer>, which
		// indicates a Cobra ShellCompDirective.  We do this for plugins
		// that use Cobra or the ones that wish to use this directive to
		// communicate a special behavior for the shell.
		if len(comps) > 0 {
			lastLine := comps[len(comps)-1]
			if len(lastLine) > 1 && lastLine[0] == ':' {
				if strInt, err := strconv.Atoi(lastLine[1:]); err == nil {
					directive = cobra.ShellCompDirective(strInt)
					comps = comps[:len(comps)-1]
				}
			}
		}
	}
	return comps, directive
}