tests: nest HOMEBREW_TEMP inside TEST_TMPDIR (#554)

Library/Homebrew/test/lib/config.rb

@@ -2,10 +2,9 @@ require "tmpdir"
 require "pathname"
 
 HOMEBREW_BREW_FILE = Pathname.new(ENV["HOMEBREW_BREW_FILE"])
-HOMEBREW_TEMP = Pathname.new(ENV["HOMEBREW_TEMP"] || Dir.tmpdir)
 
 TEST_TMPDIR = ENV.fetch("HOMEBREW_TEST_TMPDIR") { |k|
-  dir = Dir.mktmpdir("homebrew_tests", HOMEBREW_TEMP)
+  dir = Dir.mktmpdir("homebrew-tests-", ENV["HOMEBREW_TEMP"] || "/tmp")
   at_exit { FileUtils.remove_entry(dir) }
   ENV[k] = dir
 }
@@ -24,6 +23,7 @@ HOMEBREW_CACHE_FORMULA = HOMEBREW_PREFIX.parent+"formula_cache"
 HOMEBREW_LOCK_DIR      = HOMEBREW_PREFIX.parent+"locks"
 HOMEBREW_CELLAR        = HOMEBREW_PREFIX.parent+"cellar"
 HOMEBREW_LOGS          = HOMEBREW_PREFIX.parent+"logs"
+HOMEBREW_TEMP          = HOMEBREW_PREFIX.parent+"temp"
 
 TESTBALL_SHA1 = "be478fd8a80fe7f29196d6400326ac91dad68c37"
 TESTBALL_SHA256 = "91e3f7930c98d7ccfb288e115ed52d06b0e5bc16fec7dce8bdda86530027067b"

Library/Homebrew/test/test_integration_cmds.rb

@@ -18,6 +18,7 @@ class IntegrationCommandTests < Homebrew::TestCase
       HOMEBREW_CACHE.children,
       HOMEBREW_LOCK_DIR.children,
       HOMEBREW_LOGS.children,
+      HOMEBREW_TEMP.children,
       HOMEBREW_PREFIX/"bin",
       HOMEBREW_PREFIX/"share",
       HOMEBREW_PREFIX/"opt",

Library/Homebrew/test/testing_env.rb

@@ -7,7 +7,7 @@ require "formulary"
 
 # Test environment setup
 (HOMEBREW_LIBRARY/"Taps/homebrew/homebrew-core/Formula").mkpath
-%w[cache formula_cache locks cellar logs].each { |d| HOMEBREW_PREFIX.parent.join(d).mkpath }
+%w[cache formula_cache locks cellar logs temp].each { |d| HOMEBREW_PREFIX.parent.join(d).mkpath }
 
 # Test fixtures and files can be found relative to this path
 TEST_DIRECTORY = File.dirname(File.expand_path(__FILE__))