Test against both JSON.dump and Float#to_s

Author: byroot

test/json/json_ryu_fallback_test.rb

@@ -134,11 +134,12 @@ def test_subnormal_edge_cases_round_trip
       # Parse the number
       result = JSON.parse(input)
 
-      # Re-parse to verify round-trip
-      result2 = JSON.parse(result.to_s)
+      # Should be bit-identical
+      assert_equal(result, JSON.parse(result.to_s),
+        "Subnormal #{input} failed round-trip test")
 
       # Should be bit-identical
-      assert_equal(result, result2,
+      assert_equal(result, JSON.parse(JSON.dump(result)),
         "Subnormal #{input} failed round-trip test")
 
       # Verify the value is in the expected subnormal range