text: #region Copyright notice and license
  
  // Protocol Buffers - Google's data interchange format
  // Copyright 2008 Google Inc.  All rights reserved.
  // http://github.com/jskeet/dotnet-protobufs/
  // Original C++/Java/Python code:
  // http://code.google.com/p/protobuf/
  //
  // Redistribution and use in source and binary forms, with or without
  // modification, are permitted provided that the following conditions are
  // met:
  //
  //     * Redistributions of source code must retain the above copyright
  // notice, this list of conditions and the following disclaimer.
  //     * Redistributions in binary form must reproduce the above
  // copyright notice, this list of conditions and the following disclaimer
  // in the documentation and/or other materials provided with the
  // distribution.
  //     * Neither the name of Google Inc. nor the names of its
  // contributors may be used to endorse or promote products derived from
  // this software without specific prior written permission.
  //
  // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  
  #endregion
  
  using System;
  using System.Collections.Generic;
  using Microsoft.VisualStudio.TestTools.UnitTesting;
  
  namespace Google.ProtocolBuffers.Collections
  {
      [TestClass]
      public class PopsicleListTest
      {
          [TestMethod]
          public void MutatingOperationsOnFrozenList()
          {
              PopsicleList<string> list = new PopsicleList<string>();
              list.MakeReadOnly();
              TestUtil.AssertNotSupported(() => list.Add(""));
              TestUtil.AssertNotSupported(() => list.Clear());
              TestUtil.AssertNotSupported(() => list.Insert(0, ""));
              TestUtil.AssertNotSupported(() => list.Remove(""));
              TestUtil.AssertNotSupported(() => list.RemoveAt(0));
              TestUtil.AssertNotSupported(() => list.Add(new[] { "", "" }));
          }
  
          [TestMethod]
          public void NonMutatingOperationsOnFrozenList()
          {
              PopsicleList<string> list = new PopsicleList<string>();
              list.MakeReadOnly();
              Assert.IsFalse(list.Contains(""));
              Assert.AreEqual(0, list.Count);
              list.CopyTo(new string[5], 0);
              list.GetEnumerator();
              Assert.AreEqual(-1, list.IndexOf(""));
              Assert.IsTrue(list.IsReadOnly);
          }
  
          [TestMethod]
          public void MutatingOperationsOnFluidList()
          {
              PopsicleList<string> list = new PopsicleList<string>();
              list.Add("");
              list.Clear();
              list.Insert(0, "");
              list.Remove("");
              list.Add("x"); // Just to make the next call valid
              list.RemoveAt(0);
          }
  
          [TestMethod]
          public void NonMutatingOperationsOnFluidList()
          {
              PopsicleList<string> list = new PopsicleList<string>();
              Assert.IsFalse(list.Contains(""));
              Assert.AreEqual(0, list.Count);
              list.CopyTo(new string[5], 0);
              list.GetEnumerator();
              Assert.AreEqual(-1, list.IndexOf(""));
              Assert.IsFalse(list.IsReadOnly);
          }
  
          [TestMethod]
          public void DoesNotAddNullEnumerable()
          {
              PopsicleList<string> list = new PopsicleList<string>();
              try
              {
                  list.Add((IEnumerable<string>)null);
              }
              catch (ArgumentNullException)
              { return; }
  
              Assert.Fail("List should not allow nulls.");
          }
  
          [TestMethod]
          public void DoesNotAddRangeWithNull()
          {
              PopsicleList<string> list = new PopsicleList<string>();
              try
              {
                  list.Add(new[] { "a", "b", null });
              }
              catch (ArgumentNullException)
              { return; }
  
              Assert.Fail("List should not allow nulls.");
          }
  
          [TestMethod]
          public void DoesNotAddNull()
          {
              PopsicleList<string> list = new PopsicleList<string>();
              try
              {
                  list.Add((string)null);
              }
              catch (ArgumentNullException)
              { return; }
  
              Assert.Fail("List should not allow nulls.");
          }
  
          [TestMethod]
          public void DoesNotSetNull()
          {
              PopsicleList<string> list = new PopsicleList<string>();
              list.Add("a");
              try
              {
                  list[0] = null;
              }
              catch (ArgumentNullException)
              { return; }
  
              Assert.Fail("List should not allow nulls.");
          }
      }
  }