From 370d236b6680303cdcbdf04b2b019a82936348d8 Mon Sep 17 00:00:00 2001
From: Bartosz Brachaczek <b.brachaczek@gmail.com>
Date: Fri, 6 Jan 2023 23:06:18 +0100
Subject: [PATCH 1/2] Opportunistically take advantage of C++20 move-out-of
 stringstream

---
 src/lib_json/json_writer.cpp | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/lib_json/json_writer.cpp b/src/lib_json/json_writer.cpp
index 0dd160e45..183bbd8d8 100644
--- a/src/lib_json/json_writer.cpp
+++ b/src/lib_json/json_writer.cpp
@@ -1246,7 +1246,7 @@ String writeString(StreamWriter::Factory const& factory, Value const& root) {
   OStringStream sout;
   StreamWriterPtr const writer(factory.newStreamWriter());
   writer->write(root, &sout);
-  return sout.str();
+  return std::move(sout).str();
 }
 
 OStream& operator<<(OStream& sout, Value const& root) {

From 5a44947ab8e6117b90be56ae322efc5a4db2086e Mon Sep 17 00:00:00 2001
From: Bartosz Brachaczek <b.brachaczek@gmail.com>
Date: Wed, 11 Jan 2023 17:21:10 +0100
Subject: [PATCH 2/2] Opportunistically take advantage of C++20 move-in/out-of
 stringstream

---
 src/lib_json/json_reader.cpp | 8 +++-----
 1 file changed, 3 insertions(+), 5 deletions(-)

diff --git a/src/lib_json/json_reader.cpp b/src/lib_json/json_reader.cpp
index 1ac5e81ab..8109e88ed 100644
--- a/src/lib_json/json_reader.cpp
+++ b/src/lib_json/json_reader.cpp
@@ -599,8 +599,7 @@ bool Reader::decodeDouble(Token& token) {
 
 bool Reader::decodeDouble(Token& token, Value& decoded) {
   double value = 0;
-  String buffer(token.start_, token.end_);
-  IStringStream is(buffer);
+  IStringStream is(String(token.start_, token.end_));
   if (!(is >> value)) {
     if (value == std::numeric_limits<double>::max())
       value = std::numeric_limits<double>::infinity();
@@ -1651,8 +1650,7 @@ bool OurReader::decodeDouble(Token& token) {
 
 bool OurReader::decodeDouble(Token& token, Value& decoded) {
   double value = 0;
-  const String buffer(token.start_, token.end_);
-  IStringStream is(buffer);
+  IStringStream is(String(token.start_, token.end_));
   if (!(is >> value)) {
     if (value == std::numeric_limits<double>::max())
       value = std::numeric_limits<double>::infinity();
@@ -1983,7 +1981,7 @@ bool parseFromStream(CharReader::Factory const& fact, IStream& sin, Value* root,
                      String* errs) {
   OStringStream ssin;
   ssin << sin.rdbuf();
-  String doc = ssin.str();
+  String doc = std::move(ssin).str();
   char const* begin = doc.data();
   char const* end = begin + doc.size();
   // Note that we do not actually need a null-terminator.