Use RTEST and add test for GH-6832

Technically we shouldn't see Qfalse now, but RTEST also compiles down to
just one branch anyways. Pretty contrived issue, but easy to fix.

1 files changed, 8 insertions, 0 deletions

diff --git a/test/ruby/test_marshal.rb b/test/ruby/test_marshal.rb
index fc5cd9e93e..6cd0b9acc3 100644
--- a/test/ruby/test_marshal.rb
+++ b/test/ruby/test_marshal.rb
@@ -92,6 +92,14 @@ class TestMarshal < Test::Unit::TestCase
     TestMarshal.instance_eval { remove_const :StructInvalidMembers }
   end
 
+  def test_load_range_as_struct
+    assert_raise(TypeError, 'GH-6832') do
+      # Can be obtained with:
+      #  $ ruby -e 'Range = Struct.new(:a, :b, :c); p Marshal.dump(Range.new(nil, nil, nil))'
+      Marshal.load("\x04\bS:\nRange\b:\x06a0:\x06b0:\x06c0")
+    end
+  end
+
   class C
     def initialize(str)
       @str = str