test/must_test.rb in maiha-must-0.1 vs test/must_test.rb in maiha-must-0.2

@@ -18,13 +18,15 @@
   def test_must_be_with_block
     assert_equal :error, 1.must.be(2) {:error}
   end
 
   def test_must_not_be_blank
-    assert_equal "ok", "ok".must.not.be.blank
-    assert_equal "ok", "ok".must.not.be.blank {"ng"}
-    assert_equal "ng",   "".must.not.be.blank {"ng"}
-    assert_raises(Invalid) {"".must.not.be.blank}
+    if Object.instance_methods.include?("blank?")
+      assert_equal "ok", "ok".must.not.be.blank
+      assert_equal "ok", "ok".must.not.be.blank {"ng"}
+      assert_equal "ng",   "".must.not.be.blank {"ng"}
+      assert_raises(Invalid) {"".must.not.be.blank}
+    end
   end
 end
 
 
 class CoercedTest < Test::Unit::TestCase