Add copying utility methods to Arena

tests/test_metric.cpp

@@ -585,32 +585,6 @@ TEST_CASE("thread counter cleanup bug") {
   }
 }
 
-TEST_CASE("error conditions") {
-  SUBCASE("counter negative increment") {
-    auto counter_family = metric::create_counter("error_counter", "Error test");
-    auto counter = counter_family.create({});
-
-    // This should abort in debug builds due to validation
-    // In release builds, behavior is undefined
-    // counter.inc(-1.0); // Would abort
-  }
-
-  SUBCASE("invalid metric names") {
-    // These should abort due to validation
-    // auto bad_counter = metric::create_counter("123invalid", "help"); // Would
-    // abort auto bad_gauge = metric::create_gauge("invalid-name", "help");   //
-    // Would abort
-  }
-
-  SUBCASE("invalid label keys") {
-    auto counter_family = metric::create_counter("valid_name", "help");
-
-    // This should abort due to label validation
-    // auto counter = counter_family.create({{"123invalid", "value"}}); // Would
-    // abort
-  }
-}
-
 TEST_CASE("memory management") {
   SUBCASE("arena allocation in render") {
     Arena arena;

tests/test_server.cpp

@@ -8,24 +8,14 @@
 #include <string_view>
 #include <thread>
 
-// Helper to copy a string into arena memory
-static std::string_view arena_copy_string(std::string_view str, Arena &arena) {
-  if (str.empty()) {
-    return std::string_view{};
-  }
-  char *copied = arena.allocate<char>(str.size());
-  std::memcpy(copied, str.data(), str.size());
-  return std::string_view(copied, str.size());
-}
-
 struct EchoHandler : ConnectionHandler {
   Arena arena;
   std::span<std::string_view> reply;
   WeakRef<MessageSender> wconn;
   std::latch done{1};
   void on_data_arrived(std::string_view data, Connection &conn) override {
-    reply = std::span{arena.allocate<std::string_view>(1), 1};
-    reply[0] = arena_copy_string(data, arena);
+    reply = arena.allocate_span<std::string_view>(1);
+    reply[0] = arena.copy_string(data);
     wconn = conn.get_weak_ref();
     CHECK(wconn.lock());
     done.count_down();