1 files changed, 7 insertions, 3 deletions
diff --git a/spec/ruby/core/rational/integer_spec.rb b/spec/ruby/core/rational/integer_spec.rb
index 451e42ee14..cd7fa97fcf 100644
--- a/spec/ruby/core/rational/integer_spec.rb
+++ b/spec/ruby/core/rational/integer_spec.rb
@@ -1,9 +1,13 @@
+require_relative "../../spec_helper"
 describe "Rational#integer?" do
-  it "returns false for a rational with a numerator and no denominator" do
-    Rational(20).integer?.should be_false
+  # Guard against the Mathn library
+  guard -> { !defined?(Math.rsqrt) } do
+    it "returns false for a rational with a numerator and no denominator" do
+      Rational(20).integer?.should == false
+    end
   end
 
   it "returns false for a rational with a numerator and a denominator" do
-    Rational(20,3).integer?.should be_false
+    Rational(20,3).integer?.should == false
   end
 end