SQ: Add test

Author: davidfstr

test/rdiscount_test.rb

@@ -21,6 +21,21 @@ def test_that_discount_does_not_blow_up_with_weird_formatting_case
     RDiscount.new(text).to_html
   end
 
+  def test_that_oversized_input_raises_argument_error
+    # mkd_string() takes an int length, so inputs > INT_MAX (2 147 483 647 bytes)
+    # must be rejected before reaching C to avoid integer truncation / overflow.
+    INT_MAX = 2_147_483_647
+    begin
+      oversized_text = 'a' * (INT_MAX + 1)
+    rescue NoMemoryError
+      skip "Insufficient memory to create oversized input for this test"
+    end
+
+    assert_raise(ArgumentError) do
+      RDiscount.new(oversized_text).to_html
+    end
+  end
+
   def test_that_smart_converts_double_quotes_to_curly_quotes
     rd = RDiscount.new(%("Quoted text"), :smart)
     assert_equal %(<p>&ldquo;Quoted text&rdquo;</p>\n), rd.to_html