From 776743bb6c1b2abc6a91a8292cf67fd0515c4fbc Mon Sep 17 00:00:00 2001
From: dota17 <chenguopingdota@163.com>
Date: Sat, 16 May 2020 15:16:31 +0800
Subject: [PATCH] fix issue 859

---
 include/yaml-cpp/node/convert.h     | 8 ++++++++
 test/integration/load_node_test.cpp | 5 +++++
 2 files changed, 13 insertions(+)

diff --git a/include/yaml-cpp/node/convert.h b/include/yaml-cpp/node/convert.h
index d6bd365..7164022 100644
--- a/include/yaml-cpp/node/convert.h
+++ b/include/yaml-cpp/node/convert.h
@@ -15,6 +15,7 @@
 #include <sstream>
 #include <type_traits>
 #include <vector>
+#include <typeinfo>
 
 #include "yaml-cpp/binary.h"
 #include "yaml-cpp/node/impl.h"
@@ -133,6 +134,13 @@ inner_encode(const T& rhs, std::stringstream& stream){
       const std::string& input = node.Scalar();                            \
       std::stringstream stream(input);                                     \
       stream.unsetf(std::ios::dec);                                        \
+      if ((stream.peek() == '-') &&                                        \
+         (typeid(rhs) == typeid(unsigned) ||                               \
+         typeid(rhs) == typeid(unsigned short) ||                          \
+         typeid(rhs) == typeid(unsigned long) ||                           \
+         typeid(rhs) == typeid(unsigned long long))) {                     \
+        return false;                                                      \
+      }                                                                    \
       if ((stream >> std::noskipws >> rhs) && (stream >> std::ws).eof()) { \
         return true;                                                       \
       }                                                                    \
diff --git a/test/integration/load_node_test.cpp b/test/integration/load_node_test.cpp
index 1d86f51..786e566 100644
--- a/test/integration/load_node_test.cpp
+++ b/test/integration/load_node_test.cpp
@@ -32,6 +32,11 @@ TEST(LoadNodeTest, NumericConversion) {
   EXPECT_EQ(-std::numeric_limits<float>::infinity(), node[4].as<float>());
   EXPECT_EQ(21, node[5].as<int>());
   EXPECT_EQ(13, node[6].as<int>());
+  // Throw error: convert signed number to unsigned number.
+  EXPECT_THROW(node[7].as<unsigned>(), TypedBadConversion<unsigned int>);
+  EXPECT_THROW(node[7].as<unsigned short>(), TypedBadConversion<unsigned short>);
+  EXPECT_THROW(node[7].as<unsigned long>(), TypedBadConversion<unsigned long>);
+  EXPECT_THROW(node[7].as<unsigned long long>(), TypedBadConversion<unsigned long long>);
 }
 
 TEST(LoadNodeTest, Binary) {