update benchmark

include/util/json_renderer.hpp

@@ -32,19 +32,20 @@ template <typename Out> struct Renderer
         write('"');
         // here we assume that vast majority of strings don't need to be escaped,
         // so we check it first and escape only if needed
-        auto size = SizeOfEscapedJSONString(string.value);
-        if (size == string.value.size())
-        {
-            write(string.value);
-        }
-        else
+        if (RequiresJSONStringEscaping(string.value))
         {
             std::string escaped;
-            escaped.reserve(size);
+            // just a guess that 16 bytes for escaped characters will be enough to avoid
+            // reallocations
+            escaped.reserve(string.value.size() + 16);
             EscapeJSONString(string.value, escaped);
 
             write(escaped);
         }
+        else
+        {
+            write(string.value);
+        }
         write('"');
     }
 

include/util/string_util.hpp

@@ -58,9 +58,8 @@ template <int length, int precision> char *printInt(char *buffer, int value)
     return buffer;
 }
 
-inline size_t SizeOfEscapedJSONString(const std::string &string)
+inline bool RequiresJSONStringEscaping(const std::string &string)
 {
-    size_t size = 0;
     for (const char letter : string)
     {
         switch (letter)
@@ -73,13 +72,12 @@ inline size_t SizeOfEscapedJSONString(const std::string &string)
         case '\n':
         case '\r':
         case '\t':
-            size += 2;
-            break;
+            return true;
         default:
-            size += 1;
+            continue;
         }
     }
-    return size;
+    return false;
 }
 
 inline void EscapeJSONString(const std::string &input, std::string &output)