From 775245262d02017cbc10cf842f7a09fd464d30a4 Mon Sep 17 00:00:00 2001
From: Andrew Lazarus <lazarus@squareup.com>
Date: Wed, 30 Aug 2017 14:36:16 -0700
Subject: [PATCH] add zsh completion for switch <formula> <version>

---
 completions/zsh/_brew | 10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/completions/zsh/_brew b/completions/zsh/_brew
index bc88f402b5..22792860dd 100644
--- a/completions/zsh/_brew
+++ b/completions/zsh/_brew
@@ -592,8 +592,14 @@ _brew_style() {
 
 # brew switch name version:
 _brew_switch() {
-  _message "name version"
-  return 1
+  local -a versions
+  if [[ -n ${words[2]} ]]; then
+    versions=(${$(brew ls "${words[2]}" --versions)#${words[2]}})
+  fi
+  _arguments -S \
+    '1::formula:__brew_formulae' \
+    "2:: :(${versions[*]})" \
+    && ret=0
 }
 
 # brew tap: