Deprecate drush completion as it is GPLv2

completion/available/drush.completion.bash

@@ -1,37 +1,2 @@
-#!/usr/bin/env bash
-#
-# bash completion support for Drush:
-#   https://github.com/drush-ops/drush
-#
-# Originally from:
-#   http://github.com/drush-ops/drush/blob/master/drush.complete.sh
-
-# Ensure drush is available.
-which drush &> /dev/null || alias drush &> /dev/null || return
-
-__drush_ps1() {
-  f="${TMPDIR:-/tmp/}/drush-env/drush-drupal-site-$$"
-  if [ -f $f ]
-  then
-    __DRUPAL_SITE=$(cat "$f")
-  else
-    __DRUPAL_SITE="$DRUPAL_SITE"
-  fi
-
-  [[ -n "$__DRUPAL_SITE" ]] && printf "${1:- (%s)}" "$__DRUPAL_SITE"
-}
-
-# Completion function, uses the "drush complete" command to retrieve
-# completions for a specific command line COMP_WORDS.
-_drush_completion() {
-  # Set IFS to newline (locally), since we only use newline separators, and
-  # need to retain spaces (or not) after completions.
-  local IFS=$'\n'
-  # The '< /dev/null' is a work around for a bug in php libedit stdin handling.
-  # Note that libedit in place of libreadline in some distributions. See:
-  # https://bugs.launchpad.net/ubuntu/+source/php5/+bug/322214
-  COMPREPLY=( $(drush --early=includes/complete.inc "${COMP_WORDS[@]}" < /dev/null 2> /dev/null) )
-}
-
-# Register our completion function. We include common short aliases for Drush.
-complete -o bashdefault -o default -o nospace -F _drush_completion d dr drush drush5 drush6 drush6 drush.php
+_log_error 'Bash completion for "drush" is now deprecated, as it used code with incompatible license.
+Please disable this completion and use the instructions from "drush" developers instead.'