diff --git a/Library/Homebrew/dev-cmd/test-bot.rb b/Library/Homebrew/dev-cmd/test-bot.rb
index 1a495d04cb..7d06b93c31 100644
--- a/Library/Homebrew/dev-cmd/test-bot.rb
+++ b/Library/Homebrew/dev-cmd/test-bot.rb
@@ -687,14 +687,13 @@ module Homebrew
         git "checkout", "-f", "master"
         git "reset", "--hard", "origin/master"
       end
-      git "clean", "-ffdx", "--exclude=/Library/Taps/"
+      git "clean", "-ffdx"
 
       Pathname.glob("{#{HOMEBREW_REPOSITORY},#{HOMEBREW_LIBRARY}/Taps/*/*}").each do |git_repo|
         next if @repository == git_repo
         git_repo.cd do
           safe_system "git", "checkout", "-f", "master"
           safe_system "git", "reset", "--hard", "origin/master"
-          safe_system "git", "clean", "-ffdx", "--exclude=/Library/Taps/"
         end
       end
 
@@ -717,14 +716,15 @@ module Homebrew
         git "stash", "pop"
         test "brew", "cleanup", "--prune=7"
         git "gc", "--auto"
-        test "git", "clean", "-ffdx", "--exclude=/Library/Taps/homebrew/homebrew-core"
+        test "git", "clean", "-ffdx"
+
+        Tap.names.each { |s| safe_system "brew", "untap", s if s != "homebrew/core" }
 
         Pathname.glob("{#{HOMEBREW_REPOSITORY},#{HOMEBREW_LIBRARY}/Taps/*/*}").each do |git_repo|
           next if @repository == git_repo
           git_repo.cd do
             safe_system "git", "checkout", "-f", "master"
             safe_system "git", "reset", "--hard", "origin/master"
-            safe_system "git", "clean", "-ffdx", "--exclude=/Library/Taps/homebrew/homebrew-core"
           end
         end