From b1c54532df55f5433e948c3bae1d5e5f1f006194 Mon Sep 17 00:00:00 2001
From: ToruNiina <niina.toru.68u@gmail.com>
Date: Thu, 14 Feb 2019 15:48:05 +0900
Subject: [PATCH] feat: improve array serialization

- make multiline array more clean
- short-circuit for empty array
---
 toml/serializer.hpp | 25 +++++++++++++++++++++++--
 1 file changed, 23 insertions(+), 2 deletions(-)

diff --git a/toml/serializer.hpp b/toml/serializer.hpp
index 480fc3c..d42e45c 100644
--- a/toml/serializer.hpp
+++ b/toml/serializer.hpp
@@ -203,6 +203,10 @@ struct serializer
             }
             return token;
         }
+        if(v.empty())
+        {
+            return std::string("[]");
+        }
 
         // not an array of tables. normal array. first, try to make it inline.
         {
@@ -216,11 +220,28 @@ struct serializer
 
         // if the length exceeds this->width_, print multiline array
         std::string token;
+        std::string current_line;
         token += "[\n";
         for(const auto& item : v)
         {
-            token += toml::visit(*this, item);
-            token += ",\n";
+            const auto next_elem = toml::visit(*this, item);
+            if(current_line.size() + next_elem.size() + 1 < this->width_)
+            {
+                current_line += next_elem;
+                current_line += ',';
+            }
+            else if(current_line.empty())
+            {
+                // the next elem cannot be within the width.
+                token += next_elem;
+                token += ",\n";
+            }
+            else
+            {
+                token += current_line;
+                token += ",\n";
+                current_line = next_elem;
+            }
         }
         token += "]\n";
         return token;