From 60765fcaafabfc3b26fca2a2ab5fc0c609a55052 Mon Sep 17 00:00:00 2001
From: BlackMATov <blackmatov@gmail.com>
Date: Sat, 4 May 2019 17:44:47 +0700
Subject: [PATCH] first flat_map impl and tests

---
 flat_map.hpp       | 127 +++++++++++++------------
 flat_map_tests.cpp | 225 +++++++++++++++++++++++++++++++++++----------
 2 files changed, 245 insertions(+), 107 deletions(-)

diff --git a/flat_map.hpp b/flat_map.hpp
index c223ad5..b117b2a 100644
--- a/flat_map.hpp
+++ b/flat_map.hpp
@@ -22,7 +22,27 @@ namespace flat_hpp
              , typename Compare = std::less<Key>
              , typename Allocator = std::allocator<std::pair<Key, Value>> >
     class flat_map final {
-        using data_type = std::vector<std::pair<Key, Value>, Allocator>;
+        using data_type = std::vector<
+            std::pair<Key, Value>,
+            Allocator>;
+
+        class uber_comparer_type : public Compare {
+        public:
+            uber_comparer_type() = default;
+            uber_comparer_type(const Compare& c) : Compare(c) {}
+
+            bool operator()(const Key& l, const Key& r) const {
+                return Compare::operator()(l, r);
+            }
+
+            bool operator()(const Key& l, typename data_type::const_reference r) const {
+                return Compare::operator()(l, r.first);
+            }
+
+            bool operator()(typename data_type::const_reference l, const Key& r) const {
+                return Compare::operator()(l.first, r);
+            }
+        };
     public:
         using key_type = Key;
         using mapped_type = Value;
@@ -44,7 +64,7 @@ namespace flat_hpp
         using reverse_iterator = typename data_type::reverse_iterator;
         using const_reverse_iterator = typename data_type::const_reverse_iterator;
 
-        class value_compare final : public std::binary_function<value_type, value_type, bool> {
+        class value_compare final {
         public:
             bool operator()(const value_type& l, const value_type& r) const {
                 return compare_(l.first, r.first);
@@ -92,19 +112,19 @@ namespace flat_hpp
         }
 
         flat_map(
-            std::initializer_list<value_type> il,
+            std::initializer_list<value_type> ilist,
             const Allocator& a)
         : data_(a) {
-            insert(il.begin(), il.end());
+            insert(ilist);
         }
 
         flat_map(
-            std::initializer_list<value_type> il,
+            std::initializer_list<value_type> ilist,
             const Compare& c = Compare(),
             const Allocator& a = Allocator())
         : data_(a)
         , compare_(c) {
-            insert(il.begin(), il.end());
+            insert(ilist);
         }
 
         iterator begin() noexcept { return data_.begin(); }
@@ -160,36 +180,37 @@ namespace flat_hpp
         }
 
         std::pair<iterator, bool> insert(const value_type& value) {
-            bool found = true;
-            iterator iter = lower_bound(value.first);
-            if ( iter == end() || compare_(value.first, iter->first) ) {
-                iter = data_.insert(iter, value);
-                found = false;
-            }
-            return std::make_pair(iter, !found);
+            const iterator iter = lower_bound(value.first);
+            return iter == end() || compare_(value.first, iter->first)
+                ? std::make_pair(data_.insert(iter, value), true)
+                : std::make_pair(iter, false);
         }
 
-        std::pair<iterator, bool> insert(const_iterator hint, const value_type& value) {
-            //TODO(BlackMat): implme
-            return insert(value);
+        iterator insert(const_iterator hint, const value_type& value) {
+            return (hint == begin() || compare_((hint - 1)->first, value.first))
+                && (hint == end() || compare_(value.first, hint->first))
+                ? data_.insert(hint, std::move(value))
+                : insert(std::move(value)).first;
         }
 
         template < typename InputIter >
         void insert(InputIter first, InputIter last) {
-            for ( auto iter = first; iter != last; ++iter ) {
-                insert(*iter);
+            while ( first != last ) {
+                insert(*first++);
             }
         }
 
+        void insert(std::initializer_list<value_type> ilist) {
+            insert(ilist.begin(), ilist.end());
+        }
+
         template < typename... Args >
         std::pair<iterator, bool> emplace(Args&&... args) {
-            //TODO(BlackMat): implme
             return insert(value_type(std::forward<Args>(args)...));
         }
 
         template < typename... Args >
-        std::pair<iterator, bool> emplace_hint(const_iterator hint, Args&&... args) {
-            //TODO(BlackMat): implme
+        iterator emplace_hint(const_iterator hint, Args&&... args) {
             return insert(hint, value_type(std::forward<Args>(args)...));
         }
 
@@ -198,22 +219,24 @@ namespace flat_hpp
         }
 
         iterator erase(const_iterator iter) {
-            //TODO(BlackMat): implme
-            return end();
+            return data_.erase(iter);
         }
 
         iterator erase(const_iterator first, const_iterator last) {
-            //TODO(BlackMat): implme
-            return end();
+            return data_.erase(first, last);
         }
 
-        iterator erase(const key_type& key) {
-            //TODO(BlackMat): implme
-            return end();
+        size_type erase(const key_type& key) {
+            const iterator iter = find(key);
+            return iter != end()
+                ? (erase(iter), 1)
+                : 0;
         }
 
         void swap(flat_map& other) {
-            //TODO(BlackMat): implme
+            using std::swap;
+            swap(data_, other.data_);
+            swap(compare_, other.compare_);
         }
 
         size_type count(const key_type& key) const {
@@ -222,57 +245,41 @@ namespace flat_hpp
         }
 
         iterator find(const key_type& key) {
-            iterator iter = lower_bound(key);
-            if ( iter != end() && compare_(key, iter->first) ) {
-                iter = end();
-            }
-            return iter;
+            const iterator iter = lower_bound(key);
+            return iter != end() && !compare_(key, iter->first)
+                ? iter
+                : end();
         }
 
         const_iterator find(const key_type& key) const {
-            const_iterator iter = lower_bound(key);
-            if ( iter != end() && compare_(key, iter->first) ) {
-                iter = end();
-            }
-            return iter;
+            const const_iterator iter = lower_bound(key);
+            return iter != end() && !compare_(key, iter->first)
+                ? iter
+                : end();
         }
 
         std::pair<iterator, iterator> equal_range(const key_type& key) {
-            //TODO(BlackMat): implme
-            return {end(), end()};
+            return std::equal_range(begin(), end(), key, compare_);
         }
 
         std::pair<const_iterator, const_iterator> equal_range(const key_type& key) const {
-            //TODO(BlackMat): implme
-            return {end(), end()};
+            return std::equal_range(begin(), end(), key, compare_);
         }
 
         iterator lower_bound(const key_type& key) {
-            //TODO(BlackMat): implme
-            return std::lower_bound(begin(), end(), key, [this](const value_type& l, const key_type& r){
-                return compare_(l.first, r);
-            });
+            return std::lower_bound(begin(), end(), key, compare_);
         }
 
         const_iterator lower_bound(const key_type& key) const {
-            //TODO(BlackMat): implme
-            return std::lower_bound(begin(), end(), key, [this](const value_type& l, const key_type& r){
-                return compare_(l.first, r);
-            });
+            return std::lower_bound(begin(), end(), key, compare_);
         }
 
         iterator upper_bound(const key_type& key) {
-            //TODO(BlackMat): implme
-            return std::upper_bound(begin(), end(), key, [this](const key_type& l, const value_type& r){
-                return compare_(l, r.first);
-            });
+            return std::upper_bound(begin(), end(), key, compare_);
         }
 
         const_iterator upper_bound(const key_type& key) const {
-            //TODO(BlackMat): implme
-            return std::upper_bound(begin(), end(), key, [this](const key_type& l, const value_type& r){
-                return compare_(l, r.first);
-            });
+            return std::upper_bound(begin(), end(), key, compare_);
         }
 
         key_compare key_comp() const {
@@ -284,7 +291,7 @@ namespace flat_hpp
         }
     private:
         data_type data_;
-        key_compare compare_;
+        uber_comparer_type compare_;
     };
 }
 
diff --git a/flat_map_tests.cpp b/flat_map_tests.cpp
index aab7a16..fa2eeeb 100644
--- a/flat_map_tests.cpp
+++ b/flat_map_tests.cpp
@@ -78,19 +78,32 @@ TEST_CASE("flat_map") {
             std::less<int>,
             alloc_t>;
 
+        using map2_t = flat_map<
+            int,
+            unsigned,
+            std::greater<int>,
+            alloc_t>;
+
         {
             auto s0 = map_t();
-            auto s1 = map_t(alloc_t());
+            auto s1 = map2_t(alloc_t());
             auto s2 = map_t(std::less<int>());
-            auto s3 = map_t(std::less<int>(), alloc_t());
+            auto s3 = map2_t(std::greater<int>(), alloc_t());
         }
 
         {
-            std::vector<std::pair<int,unsigned>> v;
+            using vec_t = std::vector<std::pair<int,unsigned>>;
+
+            vec_t v{{1,30},{2,20},{3,10}};
             auto s0 = map_t(v.cbegin(), v.cend());
-            auto s1 = map_t(v.cbegin(), v.cend(), alloc_t());
+            auto s1 = map2_t(v.cbegin(), v.cend(), alloc_t());
             auto s2 = map_t(v.cbegin(), v.cend(), std::less<int>());
-            auto s3 = map_t(v.cbegin(), v.cend(), std::less<int>(), alloc_t());
+            auto s3 = map2_t(v.cbegin(), v.cend(), std::greater<int>(), alloc_t());
+
+            REQUIRE(vec_t(s0.begin(), s0.end()) == vec_t({{1,30},{2,20},{3,10}}));
+            REQUIRE(vec_t(s1.begin(), s1.end()) == vec_t({{3,10},{2,20},{1,30}}));
+            REQUIRE(vec_t(s2.begin(), s2.end()) == vec_t({{1,30},{2,20},{3,10}}));
+            REQUIRE(vec_t(s3.begin(), s3.end()) == vec_t({{3,10},{2,20},{1,30}}));
         }
 
         {
@@ -103,16 +116,40 @@ TEST_CASE("flat_map") {
     SECTION("capacity") {
         using map_t = flat_map<int, unsigned>;
         map_t s0;
-        s0.empty();
-        s0.size();
-        s0.max_size();
+
+        REQUIRE(s0.empty());
+        REQUIRE_FALSE(s0.size());
+        REQUIRE(s0.max_size() == std::allocator<std::pair<int,unsigned>>().max_size());
+
+        s0.insert({2,42});
+
+        REQUIRE_FALSE(s0.empty());
+        REQUIRE(s0.size() == 1u);
+        REQUIRE(s0.max_size() == std::allocator<std::pair<int,unsigned>>().max_size());
+
+        s0.insert({2,84});
+        REQUIRE(s0.size() == 1u);
+
+        s0.insert({3,84});
+        REQUIRE(s0.size() == 2u);
+
+        s0.clear();
+
+        REQUIRE(s0.empty());
+        REQUIRE_FALSE(s0.size());
+        REQUIRE(s0.max_size() == std::allocator<std::pair<int,unsigned>>().max_size());
     }
     SECTION("access") {
         using map_t = flat_map<int, unsigned>;
         map_t s0;
         s0[1] = 42;
-        s0.at(1);
-        my_as_const(s0).at(1);
+        REQUIRE(s0 == map_t{{1,42}});
+        s0[1] = 84;
+        REQUIRE(s0 == map_t{{1,84}});
+
+        REQUIRE(s0.at(1) == 84);
+        REQUIRE(my_as_const(s0).at(1) == 84);
+        REQUIRE_THROWS_AS(s0.at(0), std::out_of_range);
     }
     SECTION("inserts") {
         struct obj_t {
@@ -122,61 +159,155 @@ TEST_CASE("flat_map") {
             bool operator<(const obj_t& o) const {
                 return i < o.i;
             }
+
+            bool operator==(const obj_t& o) const {
+                return i == o.i;
+            }
         };
 
         using map_t = flat_map<int, obj_t>;
 
         {
             map_t s0;
-            s0.insert(std::make_pair(1, 42));
-            s0.insert(std::make_pair(2, obj_t(42)));
-            s0.insert(s0.cend(), std::make_pair(3, 84));
+
+            auto i0 = s0.insert(std::make_pair(1, 42));
+            REQUIRE(s0 == map_t{{1,42}});
+            REQUIRE(i0 == std::make_pair(s0.begin(), true));
+
+            auto i1 = s0.insert(std::make_pair(1, obj_t(42)));
+            REQUIRE(s0 == map_t{{1,42}});
+            REQUIRE(i1 == std::make_pair(s0.begin(), false));
+
+            auto i2 = s0.insert(std::make_pair(2, obj_t(42)));
+            REQUIRE(s0 == map_t{{1,42},{2,42}});
+            REQUIRE(i2 == std::make_pair(s0.begin() + 1, true));
+
+            auto i3 = s0.insert(s0.cend(), std::make_pair(3, 84));
+            REQUIRE(i3 == s0.begin() + 2);
+
             s0.insert(s0.cend(), std::make_pair(4, obj_t(84)));
-            s0.emplace(5, 100500);
-            s0.emplace_hint(s0.cend(), 6, 100500);
+
+            auto i4 = s0.emplace(5, 100500);
+            REQUIRE(i4 == std::make_pair(s0.end() - 1, true));
+            REQUIRE(s0 == map_t{{1,42},{2,42},{3,84},{4,84},{5,100500}});
+
+            auto i5 = s0.emplace_hint(s0.cend(), 6, 100500);
+            REQUIRE(s0 == map_t{{1,42},{2,42},{3,84},{4,84},{5,100500},{6,100500}});
         }
     }
     SECTION("erasers") {
         using map_t = flat_map<int, unsigned>;
-        map_t s0;
-        s0.clear();
-        s0.erase(s0.begin());
-        s0.erase(s0.cbegin());
-        s0.erase(s0.begin(), s0.end());
-        s0.erase(s0.cbegin(), s0.cend());
-        s0.erase(42);
-        map_t s1;
-        s0.swap(s1);
-        swap(s0, s1);
+        {
+            map_t s0{{1,2},{2,3},{3,4}};
+            s0.clear();
+            REQUIRE(s0.empty());
+        }
+        {
+            map_t s0{{1,2},{2,3},{3,4}};
+            auto i = s0.erase(s0.find(2));
+            REQUIRE(i == s0.begin() + 1);
+            REQUIRE(s0 == map_t{{1,2},{3,4}});
+        }
+        {
+            map_t s0{{1,2},{2,3},{3,4}};
+            auto i = s0.erase(s0.begin() + 1, s0.end());
+            REQUIRE(i == s0.end());
+            REQUIRE(s0 == map_t{{1,2}});
+        }
+        {
+            map_t s0{{1,2},{2,3},{3,4}};
+            REQUIRE(s0.erase(1) == 1);
+            REQUIRE(s0.erase(6) == 0);
+            REQUIRE(s0 == map_t{{2,3},{3,4}});
+        }
+        {
+            map_t s0{{1,2},{2,3},{3,4}};
+            map_t s1{{2,3},{3,4},{5,6}};
+            s0.swap(s1);
+            REQUIRE(s0 == map_t{{2,3},{3,4},{5,6}});
+            REQUIRE(s1 == map_t{{1,2},{2,3},{3,4}});
+            swap(s1, s0);
+            REQUIRE(s0 == map_t{{1,2},{2,3},{3,4}});
+            REQUIRE(s1 == map_t{{2,3},{3,4},{5,6}});
+        }
     }
     SECTION("lookup") {
         using map_t = flat_map<int, unsigned>;
-        map_t s0;
-        s0.count(10);
-        s0.find(10);
-        my_as_const(s0).find(10);
-        s0.equal_range(20);
-        my_as_const(s0).equal_range(20);
-        s0.lower_bound(30);
-        my_as_const(s0).lower_bound(30);
-        s0.upper_bound(30);
-        my_as_const(s0).upper_bound(30);
+        {
+            map_t s0{{1,2},{2,3},{3,4},{4,5},{5,6}};
+            REQUIRE(s0.count(3));
+            REQUIRE_FALSE(s0.count(6));
+            REQUIRE(my_as_const(s0).count(5));
+            REQUIRE_FALSE(my_as_const(s0).count(0));
+        }
+        {
+            map_t s0{{1,2},{2,3},{3,4},{4,5},{5,6}};
+            REQUIRE(s0.find(2) == s0.begin() + 1);
+            REQUIRE(my_as_const(s0).find(3) == s0.cbegin() + 2);
+            REQUIRE(s0.find(6) == s0.end());
+            REQUIRE(my_as_const(s0).find(0) == s0.cend());
+        }
+        {
+            map_t s0{{1,2},{2,3},{3,4},{4,5},{5,6}};
+            REQUIRE(s0.equal_range(3) == std::make_pair(s0.begin() + 2, s0.begin() + 3));
+            REQUIRE(s0.equal_range(6) == std::make_pair(s0.end(), s0.end()));
+            REQUIRE(my_as_const(s0).equal_range(3) == std::make_pair(s0.cbegin() + 2, s0.cbegin() + 3));
+            REQUIRE(my_as_const(s0).equal_range(0) == std::make_pair(s0.cbegin(), s0.cbegin()));
+        }
+        {
+            map_t s0{{0,1},{3,2},{6,3}};
+            REQUIRE(s0.lower_bound(0) == s0.begin());
+            REQUIRE(s0.lower_bound(1) == s0.begin() + 1);
+            REQUIRE(s0.lower_bound(10) == s0.end());
+            REQUIRE(my_as_const(s0).lower_bound(-1) == s0.cbegin());
+            REQUIRE(my_as_const(s0).lower_bound(7) == s0.cbegin() + 3);
+        }
     }
     SECTION("observers") {
-        using map_t = flat_map<int, unsigned>;
-        map_t s0;
-        my_as_const(s0).key_comp();
-        my_as_const(s0).value_comp();
+        struct my_less {
+            int i;
+            my_less(int i) : i(i) {}
+            bool operator()(int l, int r) const {
+                return l < r;
+            }
+        };
+        using map_t = flat_map<int, unsigned, my_less>;
+        map_t s0(my_less(42));
+        REQUIRE(my_as_const(s0).key_comp().i == 42);
+        REQUIRE(my_as_const(s0).value_comp()({2,50},{4,20}));
     }
     SECTION("operators") {
         using map_t = flat_map<int, unsigned>;
-        map_t s0;
-        map_t s1;
-        REQUIRE(s0 == s1);
-        REQUIRE_FALSE(s0 != s1);
-        REQUIRE_FALSE(s0 < s1);
-        REQUIRE_FALSE(s0 > s1);
-        REQUIRE(s0 <= s1);
-        REQUIRE(s0 >= s1);
+
+        REQUIRE(map_t{{1,2},{3,4}} == map_t{{3,4},{1,2}});
+        REQUIRE_FALSE(map_t{{1,2},{3,4}} == map_t{{2,4},{1,2}});
+        REQUIRE_FALSE(map_t{{1,2},{3,4}} == map_t{{1,3},{1,2}});
+        REQUIRE_FALSE(map_t{{1,2},{3,4}} == map_t{{3,4},{1,2},{0,0}});
+
+        REQUIRE_FALSE(map_t{{1,2},{3,4}} != map_t{{3,4},{1,2}});
+        REQUIRE(map_t{{1,2},{3,4}} != map_t{{2,4},{1,2}});
+        REQUIRE(map_t{{1,2},{3,4}} != map_t{{1,3},{1,2}});
+        REQUIRE(map_t{{1,2},{3,4}} != map_t{{3,4},{1,2},{0,0}});
+
+        REQUIRE(map_t{{0,2},{3,4}} < map_t{{1,2},{3,4}});
+        REQUIRE(map_t{{1,1},{3,4}} < map_t{{1,2},{3,4}});
+        REQUIRE(map_t{{1,2},{3,4}} < map_t{{1,2},{3,4},{5,6}});
+
+        REQUIRE(map_t{{0,2},{3,4}} <= map_t{{1,2},{3,4}});
+        REQUIRE(map_t{{1,1},{3,4}} <= map_t{{1,2},{3,4}});
+        REQUIRE(map_t{{1,2},{3,4}} <= map_t{{1,2},{3,4},{5,6}});
+
+        REQUIRE(map_t{{1,2},{3,4}} > map_t{{0,2},{3,4}});
+        REQUIRE(map_t{{1,2},{3,4}} > map_t{{1,1},{3,4}});
+        REQUIRE(map_t{{1,2},{3,4},{5,6}} > map_t{{1,2},{3,4}});
+
+        REQUIRE(map_t{{1,2},{3,4}} >= map_t{{0,2},{3,4}});
+        REQUIRE(map_t{{1,2},{3,4}} >= map_t{{1,1},{3,4}});
+        REQUIRE(map_t{{1,2},{3,4},{5,6}} >= map_t{{1,2},{3,4}});
+
+        REQUIRE_FALSE(map_t{{1,2},{3,4}} < map_t{{1,2},{3,4}});
+        REQUIRE(map_t{{1,2},{3,4}} <= map_t{{1,2},{3,4}});
+        REQUIRE_FALSE(map_t{{1,2},{3,4}} > map_t{{1,2},{3,4}});
+        REQUIRE(map_t{{1,2},{3,4}} >= map_t{{1,2},{3,4}});
     }
 }