2 files changed, 16 insertions, 0 deletions
diff --git a/test/ruby/envutil.rb b/test/ruby/envutil.rb
index 80700d6dc5..3e0c1a3f00 100644
--- a/test/ruby/envutil.rb
+++ b/test/ruby/envutil.rb
@@ -212,6 +212,10 @@ module Test
         assert_equal([true, ""], [status.success?, err], message)
         assert_operator(after.fdiv(before), :<, limit, message)
       end
+
+      def assert_is_minus_zero(f)
+        assert(1.0/f == -Float::INFINITY, "#{f} is not -0.0")
+      end
     end
   end
 end
diff --git a/test/ruby/test_float.rb b/test/ruby/test_float.rb
index 1935cfdd52..f561d00158 100644
--- a/test/ruby/test_float.rb
+++ b/test/ruby/test_float.rb
@@ -195,6 +195,18 @@ class TestFloat < Test::Unit::TestCase
     assert_raise(TypeError) { 2.0.send(:%, nil) }
   end
 
+  def test_modulo3
+    bug6048 = '[ruby-core:42726]'
+    assert_equal(4.2, 4.2.send(:%, Float::INFINITY))
+    assert_equal(4.2, 4.2 % Float::INFINITY)
+    assert_is_minus_zero(-0.0 % 4.2)
+    assert_is_minus_zero(-0.0.send :%, 4.2)
+    assert_raise(ZeroDivisionError) { 4.2.send(:%, 0.0) }
+    assert_raise(ZeroDivisionError) { 4.2 % 0.0 }
+    assert_raise(ZeroDivisionError) { 42.send(:%, 0) }
+    assert_raise(ZeroDivisionError) { 42 % 0 }
+  end
+
   def test_divmod2
     assert_equal([1.0, 0.0], 2.0.divmod(2))
     assert_equal([1.0, 0.0], 2.0.divmod((2**32).coerce(2).first))