improve (completion): simplify grunt completion using built in

completion/available/grunt.completion.bash

@@ -1,75 +1,6 @@
-#!/bin/bash
-
-# grunt-cli
-# http://gruntjs.com/
-#
-# Copyright jQuery Foundation and other contributors, https://jquery.org/
-
-# This software consists of voluntary contributions made by many
-# individuals. For exact contribution history, see the revision history
-# available at https://github.com/gruntjs/grunt .
-
-# The following license applies to all parts of this software except as
-# documented below:
-
-# ====
-
-# Permission is hereby granted, free of charge, to any person obtaining
-# a copy of this software and associated documentation files (the
-# "Software"), to deal in the Software without restriction, including
-# without limitation the rights to use, copy, modify, merge, publish,
-# distribute, sublicense, and/or sell copies of the Software, and to
-# permit persons to whom the Software is furnished to do so, subject to
-# the following conditions:
-
-# The above copyright notice and this permission notice shall be
-# included in all copies or substantial portions of the Software.
-
-# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
-# EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
-# MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
-# NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
-# LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
-# OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
-# WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
-
-# Usage:
-#
-# To enable bash <tab> completion for grunt, add the following line (minus the
-# leading #, which is the bash comment character) to your ~/.bashrc file:
-#
-# eval "$(grunt --completion=bash)"
+# shellcheck shell=bash
 
 # Search the current directory and all parent directories for a gruntfile.
-function _grunt_gruntfile() {
-  local curpath="$PWD"
-  while [[ "$curpath" ]]; do
-    for gruntfile in "$curpath/"{G,g}runtfile.{js,coffee}; do
-      if [[ -e "$gruntfile" ]]; then
-        echo "$gruntfile"
-        return
-      fi
-    done
-    curpath="${curpath%/*}"
-  done
-  return 1
-}
-
-# Enable bash autocompletion.
-function _grunt_completions() {
-  # The currently-being-completed word.
-  local cur="${COMP_WORDS[COMP_CWORD]}"
-  # The current gruntfile, if it exists.
-  local gruntfile="$(_grunt_gruntfile)"
-  # The current grunt version, available tasks, options, etc.
-  local gruntinfo="$(grunt --version --verbose 2>/dev/null)"
-  # Options and tasks.
-  local opts="$(echo "$gruntinfo" | awk '/Available options: / {$1=$2=""; print $0}')"
-  local compls="$(echo "$gruntinfo" | awk '/Available tasks: / {$1=$2=""; print $0}')"
-  # Only add -- or - options if the user has started typing -
-  [[ "$cur" == -* ]] && compls="$compls $opts"
-  # Tell complete what stuff to show.
-  COMPREPLY=($(compgen -W "$compls" -- "$cur"))
-}
-
-complete -o default -F _grunt_completions grunt
+if _command_exists grunt; then
+	eval "$(grunt --completion=bash)"
+fi