From f13af83a9499dd26998f482111ca3c654a231279 Mon Sep 17 00:00:00 2001
From: Niels Lohmann <mail@nlohmann.me>
Date: Tue, 28 Jul 2020 21:47:06 +0200
Subject: [PATCH] :bug: add more functions from std::map to
 nlohmann::ordered_map

---
 include/nlohmann/ordered_map.hpp |  69 +++++++++++++
 single_include/nlohmann/json.hpp |  69 +++++++++++++
 test/src/unit-ordered_map.cpp    | 167 +++++++++++++++++++++++++++++++
 test/src/unit-regression.cpp     |   3 +
 4 files changed, 308 insertions(+)

diff --git a/include/nlohmann/ordered_map.hpp b/include/nlohmann/ordered_map.hpp
index 5b88834f..57679091 100644
--- a/include/nlohmann/ordered_map.hpp
+++ b/include/nlohmann/ordered_map.hpp
@@ -18,6 +18,7 @@ template <class Key, class T, class IgnoredLess = std::less<Key>,
     using mapped_type = T;
     using Container = std::vector<std::pair<const Key, T>, Allocator>;
     using typename Container::iterator;
+    using typename Container::const_iterator;
     using typename Container::size_type;
     using typename Container::value_type;
 
@@ -97,6 +98,74 @@ template <class Key, class T, class IgnoredLess = std::less<Key>,
         }
         return 0;
     }
+
+    iterator erase(iterator pos)
+    {
+        auto it = pos;
+
+        // Since we cannot move const Keys, re-construct them in place
+        for (auto next = it; ++next != this->end(); ++it)
+        {
+            it->~value_type(); // Destroy but keep allocation
+            new (&*it) value_type{std::move(*next)};
+        }
+        Container::pop_back();
+        return pos;
+    }
+
+    size_type count(const Key& key) const
+    {
+        for (auto it = this->begin(); it != this->end(); ++it)
+        {
+            if (it->first == key)
+            {
+                return 1;
+            }
+        }
+        return 0;
+    }
+
+    iterator find(const Key& key)
+    {
+        for (auto it = this->begin(); it != this->end(); ++it)
+        {
+            if (it->first == key)
+            {
+                return it;
+            }
+        }
+        return Container::end();
+    }
+
+    const_iterator find(const Key& key) const
+    {
+        for (auto it = this->begin(); it != this->end(); ++it)
+        {
+            if (it->first == key)
+            {
+                return it;
+            }
+        }
+        return Container::end();
+    }
+
+    std::pair<iterator, bool> insert( value_type&& value )
+    {
+        return emplace(value.first, std::move(value.second));
+    }
+
+    std::pair<iterator, bool> insert( const value_type& value )
+    {
+        for (auto it = this->begin(); it != this->end(); ++it)
+        {
+            if (it->first == value.first)
+            {
+                return {it, false};
+            }
+        }
+        Container::push_back(value);
+        return {--this->end(), true};
+    }
 };
 
 }  // namespace nlohmann
diff --git a/single_include/nlohmann/json.hpp b/single_include/nlohmann/json.hpp
index dfdde16f..9c66a845 100644
--- a/single_include/nlohmann/json.hpp
+++ b/single_include/nlohmann/json.hpp
@@ -16408,6 +16408,7 @@ template <class Key, class T, class IgnoredLess = std::less<Key>,
     using mapped_type = T;
     using Container = std::vector<std::pair<const Key, T>, Allocator>;
     using typename Container::iterator;
+    using typename Container::const_iterator;
     using typename Container::size_type;
     using typename Container::value_type;
 
@@ -16487,6 +16488,74 @@ template <class Key, class T, class IgnoredLess = std::less<Key>,
         }
         return 0;
     }
+
+    iterator erase(iterator pos)
+    {
+        auto it = pos;
+
+        // Since we cannot move const Keys, re-construct them in place
+        for (auto next = it; ++next != this->end(); ++it)
+        {
+            it->~value_type(); // Destroy but keep allocation
+            new (&*it) value_type{std::move(*next)};
+        }
+        Container::pop_back();
+        return pos;
+    }
+
+    size_type count(const Key& key) const
+    {
+        for (auto it = this->begin(); it != this->end(); ++it)
+        {
+            if (it->first == key)
+            {
+                return 1;
+            }
+        }
+        return 0;
+    }
+
+    iterator find(const Key& key)
+    {
+        for (auto it = this->begin(); it != this->end(); ++it)
+        {
+            if (it->first == key)
+            {
+                return it;
+            }
+        }
+        return Container::end();
+    }
+
+    const_iterator find(const Key& key) const
+    {
+        for (auto it = this->begin(); it != this->end(); ++it)
+        {
+            if (it->first == key)
+            {
+                return it;
+            }
+        }
+        return Container::end();
+    }
+
+    std::pair<iterator, bool> insert( value_type&& value )
+    {
+        return emplace(value.first, std::move(value.second));
+    }
+
+    std::pair<iterator, bool> insert( const value_type& value )
+    {
+        for (auto it = this->begin(); it != this->end(); ++it)
+        {
+            if (it->first == value.first)
+            {
+                return {it, false};
+            }
+        }
+        Container::push_back(value);
+        return {--this->end(), true};
+    }
 };
 
 }  // namespace nlohmann
diff --git a/test/src/unit-ordered_map.cpp b/test/src/unit-ordered_map.cpp
index 78871af0..49937aa2 100644
--- a/test/src/unit-ordered_map.cpp
+++ b/test/src/unit-ordered_map.cpp
@@ -122,4 +122,171 @@ TEST_CASE("ordered_map")
             CHECK(om.size() == 4);
         }
     }
+
+    SECTION("erase")
+    {
+        ordered_map<std::string, std::string> om;
+        om["eins"] = "one";
+        om["zwei"] = "two";
+        om["drei"] = "three";
+
+        {
+            auto it = om.begin();
+            CHECK(it->first == "eins");
+            ++it;
+            CHECK(it->first == "zwei");
+            ++it;
+            CHECK(it->first == "drei");
+            ++it;
+            CHECK(it == om.end());
+        }
+
+        SECTION("with Key&&")
+        {
+            CHECK(om.size() == 3);
+            CHECK(om.erase(std::string("eins")) == 1);
+            CHECK(om.size() == 2);
+            CHECK(om.erase(std::string("vier")) == 0);
+            CHECK(om.size() == 2);
+
+            auto it = om.begin();
+            CHECK(it->first == "zwei");
+            ++it;
+            CHECK(it->first == "drei");
+            ++it;
+            CHECK(it == om.end());
+        }
+
+        SECTION("with const Key&&")
+        {
+            const std::string eins = "eins";
+            const std::string vier = "vier";
+            CHECK(om.size() == 3);
+            CHECK(om.erase(eins) == 1);
+            CHECK(om.size() == 2);
+            CHECK(om.erase(vier) == 0);
+            CHECK(om.size() == 2);
+
+            auto it = om.begin();
+            CHECK(it->first == "zwei");
+            ++it;
+            CHECK(it->first == "drei");
+            ++it;
+            CHECK(it == om.end());
+        }
+
+        SECTION("with string literal")
+        {
+            CHECK(om.size() == 3);
+            CHECK(om.erase("eins") == 1);
+            CHECK(om.size() == 2);
+            CHECK(om.erase("vier") == 0);
+            CHECK(om.size() == 2);
+
+            auto it = om.begin();
+            CHECK(it->first == "zwei");
+            ++it;
+            CHECK(it->first == "drei");
+            ++it;
+            CHECK(it == om.end());
+        }
+
+        SECTION("with iterator")
+        {
+            CHECK(om.size() == 3);
+            CHECK(om.begin()->first == "eins");
+            CHECK(std::next(om.begin(), 1)->first == "zwei");
+            CHECK(std::next(om.begin(), 2)->first == "drei");
+
+            auto it = om.erase(om.begin());
+            CHECK(it->first == "zwei");
+            CHECK(om.size() == 2);
+
+            auto it2 = om.begin();
+            CHECK(it2->first == "zwei");
+            ++it2;
+            CHECK(it2->first == "drei");
+            ++it2;
+            CHECK(it2 == om.end());
+        }
+    }
+
+    SECTION("count")
+    {
+        ordered_map<std::string, std::string> om;
+        om["eins"] = "one";
+        om["zwei"] = "two";
+        om["drei"] = "three";
+
+        const std::string eins("eins");
+        const std::string vier("vier");
+        CHECK(om.count("eins") == 1);
+        CHECK(om.count(std::string("eins")) == 1);
+        CHECK(om.count(eins) == 1);
+        CHECK(om.count("vier") == 0);
+        CHECK(om.count(std::string("vier")) == 0);
+        CHECK(om.count(vier) == 0);
+    }
+
+    SECTION("find")
+    {
+        ordered_map<std::string, std::string> om;
+        om["eins"] = "one";
+        om["zwei"] = "two";
+        om["drei"] = "three";
+        const auto com = om;
+
+        const std::string eins("eins");
+        const std::string vier("vier");
+        CHECK(om.find("eins") == om.begin());
+        CHECK(om.find(std::string("eins")) == om.begin());
+        CHECK(om.find(eins) == om.begin());
+        CHECK(om.find("vier") == om.end());
+        CHECK(om.find(std::string("vier")) == om.end());
+        CHECK(om.find(vier) == om.end());
+
+        CHECK(com.find("eins") == com.begin());
+        CHECK(com.find(std::string("eins")) == com.begin());
+        CHECK(com.find(eins) == com.begin());
+        CHECK(com.find("vier") == com.end());
+        CHECK(com.find(std::string("vier")) == com.end());
+        CHECK(com.find(vier) == com.end());
+    }
+
+    SECTION("insert")
+    {
+        ordered_map<std::string, std::string> om;
+        om["eins"] = "one";
+        om["zwei"] = "two";
+        om["drei"] = "three";
+
+        SECTION("const value_type&")
+        {
+            ordered_map<std::string, std::string>::value_type vt1 {"eins", "1"};
+            ordered_map<std::string, std::string>::value_type vt4 {"vier", "four"};
+
+            auto res1 = om.insert(vt1);
+            CHECK(res1.first == om.begin());
+            CHECK(res1.second == false);
+            CHECK(om.size() == 3);
+
+            auto res4 = om.insert(vt4);
+            CHECK(res4.first == om.begin() + 3);
+            CHECK(res4.second == true);
+            CHECK(om.size() == 4);
+        }
+
+        SECTION("value_type&&")
+        {
+            auto res1 = om.insert({"eins", "1"});
+            CHECK(res1.first == om.begin());
+            CHECK(res1.second == false);
+            CHECK(om.size() == 3);
+
+            auto res4 = om.insert({"vier", "four"});
+            CHECK(res4.first == om.begin() + 3);
+            CHECK(res4.second == true);
+            CHECK(om.size() == 4);
+        }
+    }
 }
diff --git a/test/src/unit-regression.cpp b/test/src/unit-regression.cpp
index 0199a0fb..f0fdd41c 100644
--- a/test/src/unit-regression.cpp
+++ b/test/src/unit-regression.cpp
@@ -1984,6 +1984,9 @@ TEST_CASE("regression tests")
         jsonAnimals.update(jsonCat);
         CHECK(jsonAnimals["animal"] == "cat");
 
+        auto jsonAnimals_parsed = nlohmann::ordered_json::parse(jsonAnimals.dump());
+        CHECK(jsonAnimals == jsonAnimals_parsed);
+
         std::vector<std::pair<std::string, int64_t>> intData = {std::make_pair("aaaa", 11),
                                                                 std::make_pair("bbb", 222)
                                                                };