From 6da85246c65fb65f0aa32e8feef4a7e0a909e510 Mon Sep 17 00:00:00 2001
From: Sam Stephenson <sam@37signals.com>
Date: Tue, 13 Sep 2011 10:13:27 -0500
Subject: [PATCH] Proof-of-concept external completions

---
 completions/rbenv.bash    | 31 ++++++++-----------------------
 libexec/rbenv-completions | 15 +++++++++++++++
 libexec/rbenv-local       |  7 +++++++
 3 files changed, 30 insertions(+), 23 deletions(-)
 create mode 100755 libexec/rbenv-completions

diff --git a/completions/rbenv.bash b/completions/rbenv.bash
index d548a859..e3276016 100644
--- a/completions/rbenv.bash
+++ b/completions/rbenv.bash
@@ -1,29 +1,14 @@
-_rbenv_commands() {
-  COMPREPLY=()
-  local cur="${COMP_WORDS[COMP_CWORD]}"
-  COMPREPLY=( $( compgen -W "$(rbenv commands)" -- $cur ) )
-}
-
-_rbenv_versions() {
-  COMPREPLY=()
-  local cur="${COMP_WORDS[COMP_CWORD]}"
-  local versions="$(echo system; rbenv versions --bare)"
-  COMPREPLY=( $( compgen -W "$versions" -- $cur ) )
-}
-
 _rbenv() {
   COMPREPLY=()
-  local cur="${COMP_WORDS[COMP_CWORD]}"
-  local prev="${COMP_WORDS[COMP_CWORD-1]}"
+  local word="${COMP_WORDS[COMP_CWORD]}"
 
-  case "$prev" in
-  set-* | global | local | shell | prefix )
-    _rbenv_versions
-    ;;
-  * )
-    _rbenv_commands
-    ;;
-  esac
+  if [ "$COMP_CWORD" -eq 1 ]; then
+    COMPREPLY=( $(compgen -W "$(rbenv commands)" -- "$word") )
+  else
+    local command="${COMP_WORDS[1]}"
+    local completions="$(rbenv completions "$command")"
+    COMPREPLY=( $(compgen -W "$completions" -- "$word") )
+  fi
 }
 
 complete -F _rbenv rbenv
diff --git a/libexec/rbenv-completions b/libexec/rbenv-completions
new file mode 100755
index 00000000..e83690dc
--- /dev/null
+++ b/libexec/rbenv-completions
@@ -0,0 +1,15 @@
+#!/usr/bin/env bash
+set -e
+[ -n "$RBENV_DEBUG" ] && set -x
+
+COMMAND="$1"
+if [ -z "$COMMAND" ]; then
+  echo "usage: rbenv completions COMMAND [arg1 arg2...]" >&2
+  exit 1
+fi
+
+COMMAND_PATH="$(command -v "rbenv-$COMMAND")"
+if grep -i "^# provide rbenv completions" "$COMMAND_PATH" >/dev/null; then
+  shift
+  exec "$COMMAND_PATH" --complete "$@"
+fi
diff --git a/libexec/rbenv-local b/libexec/rbenv-local
index e8f1c96d..d261564c 100755
--- a/libexec/rbenv-local
+++ b/libexec/rbenv-local
@@ -2,6 +2,13 @@
 set -e
 [ -n "$RBENV_DEBUG" ] && set -x
 
+# Provide rbenv completions
+if [ "$1" = "--complete" ]; then
+  shift
+  echo system
+  exec rbenv-versions --bare
+fi
+
 RBENV_VERSION="$1"
 RBENV_VERSION_FILE=".rbenv-version"