Refactored string adapters: only one IsString<T> and adaptString()

src/ArduinoJson/Strings/Adapters/StdStringAdapter.hpp

@@ -0,0 +1,52 @@
+// ArduinoJson - https://arduinojson.org
+// Copyright Benoit Blanchon 2014-2021
+// MIT License
+
+#pragma once
+
+#include <ArduinoJson/Namespace.hpp>
+#include <ArduinoJson/Strings/StoragePolicy.hpp>
+#include <ArduinoJson/Strings/StringAdapter.hpp>
+
+#include <string>
+
+namespace ARDUINOJSON_NAMESPACE {
+
+template <typename TCharTraits, typename TAllocator>
+class StringAdapter<std::basic_string<char, TCharTraits, TAllocator> > {
+ public:
+  typedef std::basic_string<char, TCharTraits, TAllocator> string_type;
+
+  StringAdapter(const string_type& str) : _str(&str) {}
+
+  void copyTo(char* p, size_t n) const {
+    memcpy(p, _str->c_str(), n);
+  }
+
+  bool isNull() const {
+    return false;
+  }
+
+  int compare(const char* other) const {
+    if (!other)
+      return 1;
+    return _str->compare(other);
+  }
+
+  bool equals(const char* expected) const {
+    if (!expected)
+      return false;
+    return *_str == expected;
+  }
+
+  size_t size() const {
+    return _str->size();
+  }
+
+  typedef storage_policies::store_by_copy storage_policy;
+
+ private:
+  const string_type* _str;
+};
+
+}  // namespace ARDUINOJSON_NAMESPACE