Extract HOMEBREW_TEMP constant

Library/Homebrew/cmd/doctor.rb

@@ -681,8 +681,7 @@ def check_for_multiple_volumes
   # Find the volumes for the TMP folder & HOMEBREW_CELLAR
   real_cellar = HOMEBREW_CELLAR.realpath
 
-  tmp_prefix = ENV['HOMEBREW_TEMP'] || '/tmp'
-  tmp = Pathname.new with_system_path { `mktemp -d #{tmp_prefix}/homebrew-brew-doctor-XXXX` }.strip
+  tmp = Pathname.new with_system_path { `mktemp -d #{HOMEBREW_TEMP}/homebrew-brew-doctor-XXXX` }.strip
   real_temp = tmp.realpath.parent
 
   where_cellar = volumes.which real_cellar
@@ -703,8 +702,7 @@ end
 
 def check_filesystem_case_sensitive
   volumes = Volumes.new
-  tmp_prefix = Pathname.new(ENV['HOMEBREW_TEMP'] || '/tmp')
-  case_sensitive_vols = [HOMEBREW_PREFIX, HOMEBREW_REPOSITORY, HOMEBREW_CELLAR, tmp_prefix].select do |dir|
+  case_sensitive_vols = [HOMEBREW_PREFIX, HOMEBREW_REPOSITORY, HOMEBREW_CELLAR, HOMEBREW_TEMP].select do |dir|
     # We select the dir as being case-sensitive if either the UPCASED or the
     # downcased variant is missing.
     # Of course, on a case-insensitive fs, both exist because the os reports so.

Library/Homebrew/extend/fileutils.rb

@@ -13,8 +13,8 @@ module FileUtils extend self
     # If the user has FileVault enabled, then we can't mv symlinks from the
     # /tmp volume to the other volume. So we let the user override the tmp
     # prefix if they need to.
-    tmp = ENV['HOMEBREW_TEMP'].chuzzle || '/tmp'
-    tempd = with_system_path { `mktemp -d #{tmp}/#{prefix}-XXXX` }.chuzzle
+
+    tempd = with_system_path { `mktemp -d #{HOMEBREW_TEMP}/#{prefix}-XXXX` }.chuzzle
     raise "Failed to create sandbox" if tempd.nil?
     prevd = pwd
     cd tempd

Library/Homebrew/global.rb

@@ -66,6 +66,8 @@ end
 
 HOMEBREW_LOGS = Pathname.new(ENV['HOMEBREW_LOGS'] || '~/Library/Logs/Homebrew/').expand_path
 
+HOMEBREW_TEMP = Pathname.new(ENV.fetch('HOMEBREW_TEMP', '/tmp'))
+
 RUBY_BIN = Pathname.new(RbConfig::CONFIG['bindir'])
 RUBY_PATH = RUBY_BIN + RbConfig::CONFIG['ruby_install_name'] + RbConfig::CONFIG['EXEEXT']
 

Library/Homebrew/keg_fix_install_names.rb

@@ -3,15 +3,13 @@ class Keg
   CELLAR_PLACEHOLDER = "@@HOMEBREW_CELLAR@@".freeze
 
   def fix_install_names options={}
-    tmp = ENV['HOMEBREW_TEMP'] ? Regexp.escape(ENV['HOMEBREW_TEMP']) : '/tmp'
-
     mach_o_files.each do |file|
       file.ensure_writable do
         change_dylib_id(dylib_id_for(file, options), file) if file.dylib?
 
         each_install_name_for(file) do |bad_name|
           # Don't fix absolute paths unless they are rooted in the build directory
-          next if bad_name.start_with? '/' and not %r[^#{tmp}] === bad_name
+          next if bad_name.start_with? '/' and not %r[^#{HOMEBREW_TEMP}] === bad_name
 
           new_name = fixed_name(file, bad_name)
           change_install_name(bad_name, new_name, file) unless new_name == bad_name