// Licensed to the .NET Foundation under one or more agreements.
// The .NET Foundation licenses this file to you under the MIT license.
// See the LICENSE file in the project root for more information.
 
using System;
using System.Collections.Generic;
 
namespace Roslyn.Utilities
{
    internal partial class SpecializedCollections
    {
        private static partial class ReadOnly
        {
            internal class Collection<TUnderlying, T> : Enumerable<TUnderlying, T>, ICollection<T>
                where TUnderlying : ICollection<T>
            {
                public Collection(TUnderlying underlying)
                    : base(underlying)
                {
                }
 
                public void Add(T item)
                {
                    throw new NotSupportedException();
                }
 
                public void Clear()
                {
                    throw new NotSupportedException();
                }
 
                public bool Contains(T item)
                {
                    return this.Underlying.Contains(item);
                }
 
                public void CopyTo(T[] array, int arrayIndex)
                {
                    this.Underlying.CopyTo(array, arrayIndex);
                }
 
                public int Count
                {
                    get
                    {
                        return this.Underlying.Count;
                    }
                }
 
                public bool IsReadOnly => true;
 
                public bool Remove(T item)
                {
                    throw new NotSupportedException();
                }
            }
        }
    }
}