From f97d8e3905f4ede7403be512df4aaeccc59147be Mon Sep 17 00:00:00 2001
From: Dominyk Tiller <dominyktiller@gmail.com>
Date: Sat, 10 Feb 2018 09:05:06 +0000
Subject: [PATCH] diagnostic: implement cache size check

---
 Library/Homebrew/diagnostic.rb | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/Library/Homebrew/diagnostic.rb b/Library/Homebrew/diagnostic.rb
index dbd6aa0c14..cc364eaaa4 100644
--- a/Library/Homebrew/diagnostic.rb
+++ b/Library/Homebrew/diagnostic.rb
@@ -835,6 +835,17 @@ module Homebrew
         EOS
       end
 
+      def check_for_large_cache
+        return unless HOMEBREW_CACHE.exist?
+        return if ENV["CI"] # CI can be expected to have a large cache.
+        cache_size = HOMEBREW_CACHE.disk_usage
+        return unless cache_size > 2_147_483_648
+        <<~EOS
+          Your HOMEBREW_CACHE is using #{disk_usage_readable(cache_size)} of disk space.
+          You may wish to consider running `brew cleanup`.
+        EOS
+      end
+
       def check_for_other_frameworks
         # Other frameworks that are known to cause problems when present
         frameworks_to_check = %w[