From b751742dfc3c8cb3d851d8c006bc514b1bfa118f Mon Sep 17 00:00:00 2001
From: Mike McQuaid <mike@mikemcquaid.com>
Date: Mon, 7 Dec 2020 14:32:56 +0000
Subject: [PATCH] diagnostic: don't complain about creatable directories that
 don't exist.

If you can write to `HOMEBREW_PREFIX` (which isn't the case for
`/usr/local` on newer macOSs) then don't complain about these
directories not existing.
---
 Library/Homebrew/diagnostic.rb | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/Library/Homebrew/diagnostic.rb b/Library/Homebrew/diagnostic.rb
index 3199df2ac5..0b9355d580 100644
--- a/Library/Homebrew/diagnostic.rb
+++ b/Library/Homebrew/diagnostic.rb
@@ -341,6 +341,8 @@ module Homebrew
       alias generic_check_tmpdir_sticky_bit check_tmpdir_sticky_bit
 
       def check_exist_directories
+        return if HOMEBREW_PREFIX.writable_real?
+
         not_exist_dirs = Keg::MUST_EXIST_DIRECTORIES.reject(&:exist?)
         return if not_exist_dirs.empty?