#if !NET_4_6
using System.Collections.Generic;

namespace LinqInternal.Collections
{
    internal class KeyValuePairEqualityComparer<TKey, TValue> : IEqualityComparer<KeyValuePair<TKey, TValue>>
    {
        private readonly IEqualityComparer<TKey> _keyComparer;
        private readonly IEqualityComparer<TValue> _valueComparer;

        public KeyValuePairEqualityComparer(IEqualityComparer<TKey> keyComparer, IEqualityComparer<TValue> valueComparer)
        {
            _keyComparer = keyComparer ?? EqualityComparer<TKey>.Default;
            _valueComparer = valueComparer ?? EqualityComparer<TValue>.Default;
        }

        public bool Equals(KeyValuePair<TKey, TValue> x, KeyValuePair<TKey, TValue> y)
        {
            return _keyComparer.Equals(x.Key, y.Key) && _valueComparer.Equals(x.Value, y.Value);
        }

        public int GetHashCode(KeyValuePair<TKey, TValue> obj)
        {
            return (_keyComparer.GetHashCode(obj.Key) * 13) + _valueComparer.GetHashCode(obj.Value);
        }
    }
}
#endif