Core/Utils: Replace boost flat_set with our own

(cherry picked from commit 42fbcf2fc5)

src/common/Containers/FlatSet.h

@@ -0,0 +1,105 @@
+/*
+ * This file is part of the TrinityCore Project. See AUTHORS file for Copyright information
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation; either version 2 of the License, or (at your
+ * option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+#ifndef TRINITYCORE_FLAT_SET_H
+#define TRINITYCORE_FLAT_SET_H
+
+#include <functional>
+#include <vector>
+
+namespace Trinity::Containers
+{
+template <class Key, class Compare = std::less<Key>, class KeyContainer = std::vector<Key>>
+class FlatSet
+{
+public:
+    using iterator = typename KeyContainer::iterator;
+    using const_iterator = typename KeyContainer::const_iterator;
+
+    bool empty() const { return _storage.empty(); }
+    auto size() const { return _storage.size(); }
+
+    auto begin()  { return _storage.begin(); }
+    auto begin() const { return _storage.begin(); }
+
+    auto end()  { return _storage.end(); }
+    auto end() const { return _storage.end(); }
+
+    auto find(Key const& value) const
+    {
+        auto end = this->end();
+        auto itr = std::lower_bound(this->begin(), end, value, Compare());
+        if (itr != end && Compare()(value, *itr))
+            itr = end;
+
+        return itr;
+    }
+
+    auto find(Key const& value)
+    {
+        auto end = this->end();
+        auto itr = std::lower_bound(this->begin(), end, value, Compare());
+        if (itr != end && Compare()(value, *itr))
+            itr = end;
+
+        return itr;
+    }
+
+    template <class... Args>
+    std::pair<iterator, bool> emplace(Args&&... args)
+    {
+        Key newElement(std::forward<Args>(args)...);
+        auto end = this->end();
+        auto itr = std::lower_bound(this->begin(), end, newElement, Compare());
+        if (itr != end && !Compare()(newElement, *itr))
+            return { itr, false };
+
+        return { _storage.emplace(itr, std::move(newElement)), true };
+    }
+
+    std::pair<iterator, bool> insert(Key const& key) { return emplace(key); }
+
+    std::size_t erase(Key const& key)
+    {
+        auto itr = this->find(key);
+        if (itr == this->end())
+            return 0;
+
+        this->erase(itr);
+        return 1;
+    }
+    auto erase(const_iterator itr) { return _storage.erase(itr); }
+
+    void clear() { _storage.clear(); }
+
+    void shrink_to_fit() { _storage.shrink_to_fit(); }
+
+    friend bool operator==(FlatSet const& left, FlatSet const& right)
+    {
+        return left._storage == right._storage;
+    }
+
+    friend bool operator!=(FlatSet const& left, FlatSet const& right)
+    {
+        return !(left == right);
+    }
+
+private:
+    KeyContainer _storage;
+};
+}
+
+#endif // TRINITYCORE_FLAT_SET_H