diff --git a/Library/Homebrew/test/global_spec.rb b/Library/Homebrew/test/global_spec.rb
index 6c34ca8838..914cb3cf84 100644
--- a/Library/Homebrew/test/global_spec.rb
+++ b/Library/Homebrew/test/global_spec.rb
@@ -8,4 +8,8 @@ describe "brew", :integration_test do
       .and not_to_output.to_stderr
       .and be_a_success
   end
+
+  it "ensures that HOMEBREW_LIBRARY=HOMEBREW_REPOSITORY/Library" do
+    expect(HOMEBREW_LIBRARY.to_s).to eq("#{HOMEBREW_REPOSITORY}/Library")
+  end
 end