Add String::New overload for string_view

Author: cacharle

napi-inl.h

@@ -20,6 +20,9 @@
 #endif  // NAPI_HAS_THREADS
 #include <type_traits>
 #include <utility>
+#if __cplusplus >= 201703L
+#include <string_view>
+#endif
 
 #if defined(__clang__) || defined(__GNUC__)
 #define NAPI_NO_SANITIZE_VPTR __attribute__((no_sanitize("vptr")))
@@ -1255,6 +1258,12 @@ inline String String::New(napi_env env, const std::u16string& val) {
   return String::New(env, val.c_str(), val.size());
 }
 
+#if __cplusplus >= 201703L
+inline String String::New(napi_env env, const std::string_view& val) {
+  return String::New(env, val.data(), val.size());
+}
+#endif
+
 inline String String::New(napi_env env, const char* val) {
   // TODO(@gabrielschulhof) Remove if-statement when core's error handling is
   // available in all supported versions.

napi.h

@@ -19,6 +19,9 @@
 #endif  // NAPI_HAS_THREADS
 #include <string>
 #include <vector>
+#if __cplusplus >= 201703L
+#include <string_view>
+#endif
 
 // VS2015 RTM has bugs with constexpr, so require min of VS2015 Update 3 (known
 // good version)
@@ -718,6 +721,14 @@ class String : public Name {
                     const std::u16string& value  ///< UTF-16 encoded C++ string
   );
 
+#if __cplusplus >= 201703L
+  /// Creates a new String value from a UTF-8 encoded C++ string view.
+  static String New(
+      napi_env env,                  ///< Node-API environment
+      const std::string_view& value  ///< UTF-8 encoded C++ string view
+  );
+#endif
+
   /// Creates a new String value from a UTF-8 encoded C string.
   static String New(
       napi_env env,      ///< Node-API environment