优化了平衡，尤其对于向后倾倒的几种极限情况进行优化

Shibo-main-TOMMY/lib/ArduinoJson/extras/tests/JsonArray/std_string.cpp

@@ -0,0 +1,32 @@
+// ArduinoJson - https://arduinojson.org
+// Copyright © 2014-2023, Benoit BLANCHON
+// MIT License
+
+#include <ArduinoJson.h>
+#include <catch.hpp>
+
+static void eraseString(std::string& str) {
+  char* p = const_cast<char*>(str.c_str());
+  while (*p)
+    *p++ = '*';
+}
+
+TEST_CASE("std::string") {
+  DynamicJsonDocument doc(4096);
+  JsonArray array = doc.to<JsonArray>();
+
+  SECTION("add()") {
+    std::string value("hello");
+    array.add(value);
+    eraseString(value);
+    REQUIRE(std::string("hello") == array[0]);
+  }
+
+  SECTION("operator[]") {
+    std::string value("world");
+    array.add("hello");
+    array[0] = value;
+    eraseString(value);
+    REQUIRE(std::string("world") == array[0]);
+  }
+}