From 7c33b3cdab633e59d159d03797017c90ffee8e18 Mon Sep 17 00:00:00 2001
From: Vincent Cogne <xpac27@gmail.com>
Date: Mon, 13 Jun 2016 04:59:31 +0200
Subject: [PATCH] Add convert specialization for std::array.

---
 include/yaml-cpp/node/convert.h | 35 +++++++++++++++++++++++++++++++++
 test/node/node_test.cpp         | 24 ++++++++++++++++++++++
 2 files changed, 59 insertions(+)

diff --git a/include/yaml-cpp/node/convert.h b/include/yaml-cpp/node/convert.h
index f388a67..f232de7 100644
--- a/include/yaml-cpp/node/convert.h
+++ b/include/yaml-cpp/node/convert.h
@@ -7,6 +7,7 @@
 #pragma once
 #endif
 
+#include <array>
 #include <limits>
 #include <list>
 #include <map>
@@ -241,6 +242,40 @@ struct convert<std::list<T> > {
   }
 };
 
+// std::array
+template <typename T, std::size_t N>
+struct convert<std::array<T, N>> {
+  static Node encode(const std::array<T, N>& rhs) {
+    Node node(NodeType::Sequence);
+    for (const auto& element : rhs) {
+      node.push_back(element);
+    }
+    return node;
+  }
+
+  static bool decode(const Node& node, std::array<T, N>& rhs) {
+    if (!isNodeValid(node)) {
+      return false;
+    }
+
+    for (auto i = 0u; i < node.size(); ++i) {
+#if defined(__GNUC__) && __GNUC__ < 4
+      // workaround for GCC 3:
+      rhs[i] = node[i].template as<T>();
+#else
+      rhs[i] = node[i].as<T>();
+#endif
+    }
+    return true;
+  }
+
+private:
+
+  static bool isNodeValid(const Node& node) {
+    return node.IsSequence() && node.size() == N;
+  }
+};
+
 // std::pair
 template <typename T, typename U>
 struct convert<std::pair<T, U> > {
diff --git a/test/node/node_test.cpp b/test/node/node_test.cpp
index 4105e72..2202f72 100644
--- a/test/node/node_test.cpp
+++ b/test/node/node_test.cpp
@@ -12,6 +12,14 @@
 using ::testing::AnyOf;
 using ::testing::Eq;
 
+#define EXPECT_THROW_REPRESENTATION_EXCEPTION(statement, message) \
+  ASSERT_THROW(statement, RepresentationException);               \
+  try {                                                   \
+    statement;                                            \
+  } catch (const RepresentationException& e) {                    \
+    EXPECT_EQ(e.msg, message);                            \
+  }
+
 namespace YAML {
 namespace {
 TEST(NodeTest, SimpleScalar) {
@@ -154,6 +162,22 @@ TEST(NodeTest, SimpleSubkeys) {
   EXPECT_EQ("monkey", node["username"].as<std::string>());
 }
 
+TEST(NodeTest, StdArray) {
+  std::array<int, 5> evens {{ 2, 4, 6, 8, 10 }};
+  Node node;
+  node["evens"] = evens;
+  std::array<int, 5> actualEvens = node["evens"].as<std::array<int, 5>>();
+  EXPECT_EQ(evens, actualEvens);
+}
+
+TEST(NodeTest, StdArrayWrongSize) {
+  std::array<int, 3> evens {{ 2, 4, 6 }};
+  Node node;
+  node["evens"] = evens;
+  EXPECT_THROW_REPRESENTATION_EXCEPTION((node["evens"].as<std::array<int, 5>>()),
+                                        ErrorMsg::BAD_CONVERSION);
+}
+
 TEST(NodeTest, StdVector) {
   std::vector<int> primes;
   primes.push_back(2);