diff --git a/Library/Homebrew/extend/os/mac/diagnostic.rb b/Library/Homebrew/extend/os/mac/diagnostic.rb
index 3e0c1d04d0..c7dabde2b9 100644
--- a/Library/Homebrew/extend/os/mac/diagnostic.rb
+++ b/Library/Homebrew/extend/os/mac/diagnostic.rb
@@ -53,8 +53,11 @@ module Homebrew
         return unless MacOS::Xcode.installed?
         return unless MacOS::Xcode.outdated?
 
-        # CI images are going to end up outdated so don't complain.
-        return if ENV["TRAVIS"] || ENV["CIRCLECI"]
+        # Travis CI images are going to end up outdated so don't complain when
+        # `brew test-bot` runs `brew doctor` in the CI for the Homebrew/brew
+        # repository. This only needs to support whatever CI provider
+        # Homebrew/brew is currently using.
+        return if ENV["TRAVIS"]
 
         message = <<-EOS.undent
           Your Xcode (#{MacOS::Xcode.version}) is outdated.