Split rbenv-version into rbenv-version-name and rbenv-version-origin, update versions, prefix, and which appropriately

libexec/rbenv-version

@@ -1,52 +1,3 @@
 #!/usr/bin/env bash -e
 
-read_version_file() {
-  egrep -m 1 '[^[:space:]]' "$1"
-}
-
-find_version_file() {
-  local root="$(pwd)"
-  while [ -n "$root" ]; do
-    if [ -e "${root}/.rbenv-version" ]; then
-      echo "${root}/.rbenv-version"
-      return 0
-    fi
-    root="${root%/*}"
-  done
-  return 1
-}
-
-DEFAULT_PATH="${HOME}/.rbenv/default"
-
-find_default_version_file() {
-  if [ -e "$DEFAULT_PATH" ]; then
-    echo "$DEFAULT_PATH"
-    return 0
-  fi
-  return 1
-}
-
-if [ -z "$RBENV_VERSION" ]; then
-  RBENV_VERSION_FILE="$(find_version_file || find_default_version_file || true)"
-
-  if [ -n "$RBENV_VERSION_FILE" ]; then
-    RBENV_VERSION="$(read_version_file "$RBENV_VERSION_FILE")"
-  else
-    echo system > "$DEFAULT_PATH"
-    RBENV_VERSION=system
-  fi
-fi
-
-if [ "$RBENV_VERSION" = "system" ]; then
-  echo "$RBENV_VERSION"
-  exit
-fi
-
-RBENV_VERSION_PATH="${HOME}/.rbenv/versions/${RBENV_VERSION}"
-
-if [ -d "$RBENV_VERSION_PATH" ]; then
-  echo "$RBENV_VERSION"
-else
-  echo "rbenv: version \`$RBENV_VERSION' is not installed" >&2
-  exit 1
-fi
+echo "$(rbenv-version-name) (set by $(rbenv-version-origin))"