Fix stack-overflow in ttype-debug

Summary: Fix infinte recursion bug for unknown ttypes

Reviewed By: hchokshi, iahs

Differential Revision: D90136336

fbshipit-source-id: 168d135a3577ea99d53cfc7ef9c5ce36ed1a67b8

Author: pranavtbhat

third-party/thrift/src/thrift/lib/cpp/protocol/TType.cpp

@@ -59,7 +59,7 @@ std::string debugStringForTType(TType type) {
     case T_FLOAT:
       return "FLOAT";
     default:
-      return fmt::format("UNKNOWN({})", type);
+      return fmt::format("UNKNOWN({})", static_cast<uint8_t>(type));
   }
 }
 

third-party/thrift/src/thrift/lib/cpp2/protocol/test/ProtocolTest.cpp

@@ -36,6 +36,11 @@ static constexpr size_t kTestingProtocolMaxDepth = 4;
 TEST(TTypeTest, Format) {
   EXPECT_EQ(fmt::format("{}", T_BOOL), "BOOL");
   EXPECT_EQ(fmt::format("{}", T_I64), "I64");
+
+  auto uint8Max = std::numeric_limits<uint8_t>::max();
+  EXPECT_EQ(
+      fmt::format("{}", static_cast<TType>(uint8Max)),
+      fmt::format("UNKNOWN({})", uint8Max));
 }
 
 template <typename ProtocolWriter>