csharp/src/Google.Protobuf.Test/CodedOutputStreamTest.cs - third_party/protobuf - Git at Google

 #region Copyright notice and license
 // Protocol Buffers - Google's data interchange format
 // Copyright 2008 Google Inc.  All rights reserved.
 // https://developers.google.com/protocol-buffers/
 //
 // 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.IO;
 using Google.Protobuf.TestProtos;
 using Google.Protobuf.Buffers;
 using NUnit.Framework;
 using System.Text;

 namespace Google.Protobuf
 {
     public class CodedOutputStreamTest
     {
         /// <summary>
         /// Writes the given value using WriteRawVarint32() and WriteRawVarint64() and
         /// checks that the result matches the given bytes
         /// </summary>
         private static void AssertWriteVarint(byte[] data, ulong value)
         {
             // Only do 32-bit write if the value fits in 32 bits.
             if ((value >> 32) == 0)
             {
                 // CodedOutputStream
                 MemoryStream rawOutput = new MemoryStream();
                 CodedOutputStream output = new CodedOutputStream(rawOutput);
                 output.WriteRawVarint32((uint) value);
                 output.Flush();
                 Assert.AreEqual(data, rawOutput.ToArray());

                 // IBufferWriter
                 var bufferWriter = new TestArrayBufferWriter<byte>();
                 WriteContext.Initialize(bufferWriter, out WriteContext ctx);
                 ctx.WriteUInt32((uint) value);
                 ctx.Flush();
                 Assert.AreEqual(data, bufferWriter.WrittenSpan.ToArray());

                 // Also try computing size.
                 Assert.AreEqual(data.Length, CodedOutputStream.ComputeRawVarint32Size((uint) value));
             }

             {
                 // CodedOutputStream
                 MemoryStream rawOutput = new MemoryStream();
                 CodedOutputStream output = new CodedOutputStream(rawOutput);
                 output.WriteRawVarint64(value);
                 output.Flush();
                 Assert.AreEqual(data, rawOutput.ToArray());

                 // IBufferWriter
                 var bufferWriter = new TestArrayBufferWriter<byte>();
                 WriteContext.Initialize(bufferWriter, out WriteContext ctx);
                 ctx.WriteUInt64(value);
                 ctx.Flush();
                 Assert.AreEqual(data, bufferWriter.WrittenSpan.ToArray());

                 // Also try computing size.
                 Assert.AreEqual(data.Length, CodedOutputStream.ComputeRawVarint64Size(value));
             }

             // Try different buffer sizes.
             for (int bufferSize = 1; bufferSize <= 16; bufferSize *= 2)
             {
                 // Only do 32-bit write if the value fits in 32 bits.
                 if ((value >> 32) == 0)
                 {
                     MemoryStream rawOutput = new MemoryStream();
                     CodedOutputStream output =
                         new CodedOutputStream(rawOutput, bufferSize);
                     output.WriteRawVarint32((uint) value);
                     output.Flush();
                     Assert.AreEqual(data, rawOutput.ToArray());

                     var bufferWriter = new TestArrayBufferWriter<byte>();
                     bufferWriter.MaxGrowBy = bufferSize;
                     WriteContext.Initialize(bufferWriter, out WriteContext ctx);
                     ctx.WriteUInt32((uint) value);
                     ctx.Flush();
                     Assert.AreEqual(data, bufferWriter.WrittenSpan.ToArray());
                 }

                 {
                     MemoryStream rawOutput = new MemoryStream();
                     CodedOutputStream output = new CodedOutputStream(rawOutput, bufferSize);
                     output.WriteRawVarint64(value);
                     output.Flush();
                     Assert.AreEqual(data, rawOutput.ToArray());

                     var bufferWriter = new TestArrayBufferWriter<byte>();
                     bufferWriter.MaxGrowBy = bufferSize;
                     WriteContext.Initialize(bufferWriter, out WriteContext ctx);
                     ctx.WriteUInt64(value);
                     ctx.Flush();
                     Assert.AreEqual(data, bufferWriter.WrittenSpan.ToArray());
                 }

             }
         }

         /// <summary>
         /// Tests WriteRawVarint32() and WriteRawVarint64()
         /// </summary>
         [Test]
         public void WriteVarint()
         {
             AssertWriteVarint(new byte[] {0x00}, 0);
             AssertWriteVarint(new byte[] {0x01}, 1);
             AssertWriteVarint(new byte[] {0x7f}, 127);
             // 14882
             AssertWriteVarint(new byte[] {0xa2, 0x74}, (0x22 << 0) | (0x74 << 7));
             // 2961488830
             AssertWriteVarint(new byte[] {0xbe, 0xf7, 0x92, 0x84, 0x0b},
                               (0x3e << 0) | (0x77 << 7) | (0x12 << 14) | (0x04 << 21) |
                               (0x0bL << 28));

             // 64-bit
             // 7256456126
             AssertWriteVarint(new byte[] {0xbe, 0xf7, 0x92, 0x84, 0x1b},
                               (0x3e << 0) | (0x77 << 7) | (0x12 << 14) | (0x04 << 21) |
                               (0x1bL << 28));
             // 41256202580718336
             AssertWriteVarint(
                 new byte[] {0x80, 0xe6, 0xeb, 0x9c, 0xc3, 0xc9, 0xa4, 0x49},
                 (0x00 << 0) | (0x66 << 7) | (0x6b << 14) | (0x1c << 21) |
                 (0x43UL << 28) | (0x49L << 35) | (0x24UL << 42) | (0x49UL << 49));
             // 11964378330978735131
             AssertWriteVarint(
                 new byte[] {0x9b, 0xa8, 0xf9, 0xc2, 0xbb, 0xd6, 0x80, 0x85, 0xa6, 0x01},
                 unchecked((ulong)
                           ((0x1b << 0) | (0x28 << 7) | (0x79 << 14) | (0x42 << 21) |
                            (0x3bL << 28) | (0x56L << 35) | (0x00L << 42) |
                            (0x05L << 49) | (0x26L << 56) | (0x01L << 63))));
         }

         /// <summary>
         /// Parses the given bytes using WriteRawLittleEndian32() and checks
         /// that the result matches the given value.
         /// </summary>
         private static void AssertWriteLittleEndian32(byte[] data, uint value)
         {
             {
                 var rawOutput = new MemoryStream();
                 var output = new CodedOutputStream(rawOutput);
                 output.WriteRawLittleEndian32(value);
                 output.Flush();
                 Assert.AreEqual(data, rawOutput.ToArray());

                 var bufferWriter = new TestArrayBufferWriter<byte>();
                 WriteContext.Initialize(bufferWriter, out WriteContext ctx);
                 ctx.WriteFixed32(value);
                 ctx.Flush();
                 Assert.AreEqual(data, bufferWriter.WrittenSpan.ToArray());
             }

             // Try different buffer sizes.
             for (int bufferSize = 1; bufferSize <= 16; bufferSize *= 2)
             {
                 var rawOutput = new MemoryStream();
                 var output = new CodedOutputStream(rawOutput, bufferSize);
                 output.WriteRawLittleEndian32(value);
                 output.Flush();
                 Assert.AreEqual(data, rawOutput.ToArray());

                 var bufferWriter = new TestArrayBufferWriter<byte>();
                 bufferWriter.MaxGrowBy = bufferSize;
                 WriteContext.Initialize(bufferWriter, out WriteContext ctx);
                 ctx.WriteFixed32(value);
                 ctx.Flush();
                 Assert.AreEqual(data, bufferWriter.WrittenSpan.ToArray());
             }
         }

         /// <summary>
         /// Parses the given bytes using WriteRawLittleEndian64() and checks
         /// that the result matches the given value.
         /// </summary>
         private static void AssertWriteLittleEndian64(byte[] data, ulong value)
         {
             {
                 var rawOutput = new MemoryStream();
                 var output = new CodedOutputStream(rawOutput);
                 output.WriteRawLittleEndian64(value);
                 output.Flush();
                 Assert.AreEqual(data, rawOutput.ToArray());

                 var bufferWriter = new TestArrayBufferWriter<byte>();
                 WriteContext.Initialize(bufferWriter, out WriteContext ctx);
                 ctx.WriteFixed64(value);
                 ctx.Flush();
                 Assert.AreEqual(data, bufferWriter.WrittenSpan.ToArray());
             }

             // Try different block sizes.
             for (int blockSize = 1; blockSize <= 16; blockSize *= 2)
             {
                 var rawOutput = new MemoryStream();
                 var output = new CodedOutputStream(rawOutput, blockSize);
                 output.WriteRawLittleEndian64(value);
                 output.Flush();
                 Assert.AreEqual(data, rawOutput.ToArray());

                 var bufferWriter = new TestArrayBufferWriter<byte>();
                 bufferWriter.MaxGrowBy = blockSize;
                 WriteContext.Initialize(bufferWriter, out WriteContext ctx);
                 ctx.WriteFixed64(value);
                 ctx.Flush();
                 Assert.AreEqual(data, bufferWriter.WrittenSpan.ToArray());
             }
         }

         /// <summary>
         /// Tests writeRawLittleEndian32() and writeRawLittleEndian64().
         /// </summary>
         [Test]
         public void WriteLittleEndian()
         {
             AssertWriteLittleEndian32(new byte[] {0x78, 0x56, 0x34, 0x12}, 0x12345678);
             AssertWriteLittleEndian32(new byte[] {0xf0, 0xde, 0xbc, 0x9a}, 0x9abcdef0);

             AssertWriteLittleEndian64(
                 new byte[] {0xf0, 0xde, 0xbc, 0x9a, 0x78, 0x56, 0x34, 0x12},
                 0x123456789abcdef0L);
             AssertWriteLittleEndian64(
                 new byte[] {0x78, 0x56, 0x34, 0x12, 0xf0, 0xde, 0xbc, 0x9a},
                 0x9abcdef012345678UL);
         }

         [Test]
         public void WriteWholeMessage_VaryingBlockSizes()
         {
             TestAllTypes message = SampleMessages.CreateFullTestAllTypes();

             byte[] rawBytes = message.ToByteArray();

             // Try different block sizes.
             for (int blockSize = 1; blockSize < 256; blockSize *= 2)
             {
                 MemoryStream rawOutput = new MemoryStream();
                 CodedOutputStream output = new CodedOutputStream(rawOutput, blockSize);
                 message.WriteTo(output);
                 output.Flush();
                 Assert.AreEqual(rawBytes, rawOutput.ToArray());

                 var bufferWriter = new TestArrayBufferWriter<byte>();
                 bufferWriter.MaxGrowBy = blockSize;
                 message.WriteTo(bufferWriter);
                 Assert.AreEqual(rawBytes, bufferWriter.WrittenSpan.ToArray());
             }
         }

         [Test]
         public void WriteContext_WritesWithFlushes()
         {
             TestAllTypes message = SampleMessages.CreateFullTestAllTypes();

             MemoryStream expectedOutput = new MemoryStream();
             CodedOutputStream output = new CodedOutputStream(expectedOutput);
             output.WriteMessage(message);
             output.Flush();
             byte[] expectedBytes1 = expectedOutput.ToArray();

             output.WriteMessage(message);
             output.Flush();
             byte[] expectedBytes2 = expectedOutput.ToArray();

             var bufferWriter = new TestArrayBufferWriter<byte>();
             WriteContext.Initialize(bufferWriter, out WriteContext ctx);
             ctx.WriteMessage(message);
             ctx.Flush();
             Assert.AreEqual(expectedBytes1, bufferWriter.WrittenSpan.ToArray());

             ctx.WriteMessage(message);
             ctx.Flush();
             Assert.AreEqual(expectedBytes2, bufferWriter.WrittenSpan.ToArray());
         }

         [Test]
         public void EncodeZigZag32()
         {
             Assert.AreEqual(0u, WritingPrimitives.EncodeZigZag32(0));
             Assert.AreEqual(1u, WritingPrimitives.EncodeZigZag32(-1));
             Assert.AreEqual(2u, WritingPrimitives.EncodeZigZag32(1));
             Assert.AreEqual(3u, WritingPrimitives.EncodeZigZag32(-2));
             Assert.AreEqual(0x7FFFFFFEu, WritingPrimitives.EncodeZigZag32(0x3FFFFFFF));
             Assert.AreEqual(0x7FFFFFFFu, WritingPrimitives.EncodeZigZag32(unchecked((int) 0xC0000000)));
             Assert.AreEqual(0xFFFFFFFEu, WritingPrimitives.EncodeZigZag32(0x7FFFFFFF));
             Assert.AreEqual(0xFFFFFFFFu, WritingPrimitives.EncodeZigZag32(unchecked((int) 0x80000000)));
         }

         [Test]
         public void EncodeZigZag64()
         {
             Assert.AreEqual(0u, WritingPrimitives.EncodeZigZag64(0));
             Assert.AreEqual(1u, WritingPrimitives.EncodeZigZag64(-1));
             Assert.AreEqual(2u, WritingPrimitives.EncodeZigZag64(1));
             Assert.AreEqual(3u, WritingPrimitives.EncodeZigZag64(-2));
             Assert.AreEqual(0x000000007FFFFFFEuL,
                             WritingPrimitives.EncodeZigZag64(unchecked((long) 0x000000003FFFFFFFUL)));
             Assert.AreEqual(0x000000007FFFFFFFuL,
                             WritingPrimitives.EncodeZigZag64(unchecked((long) 0xFFFFFFFFC0000000UL)));
             Assert.AreEqual(0x00000000FFFFFFFEuL,
                             WritingPrimitives.EncodeZigZag64(unchecked((long) 0x000000007FFFFFFFUL)));
             Assert.AreEqual(0x00000000FFFFFFFFuL,
                             WritingPrimitives.EncodeZigZag64(unchecked((long) 0xFFFFFFFF80000000UL)));
             Assert.AreEqual(0xFFFFFFFFFFFFFFFEL,
                             WritingPrimitives.EncodeZigZag64(unchecked((long) 0x7FFFFFFFFFFFFFFFUL)));
             Assert.AreEqual(0xFFFFFFFFFFFFFFFFL,
                             WritingPrimitives.EncodeZigZag64(unchecked((long) 0x8000000000000000UL)));
         }

         [Test]
         public void RoundTripZigZag32()
         {
             // Some easier-to-verify round-trip tests.  The inputs (other than 0, 1, -1)
             // were chosen semi-randomly via keyboard bashing.
             Assert.AreEqual(0, ParsingPrimitives.DecodeZigZag32(WritingPrimitives.EncodeZigZag32(0)));
             Assert.AreEqual(1, ParsingPrimitives.DecodeZigZag32(WritingPrimitives.EncodeZigZag32(1)));
             Assert.AreEqual(-1, ParsingPrimitives.DecodeZigZag32(WritingPrimitives.EncodeZigZag32(-1)));
             Assert.AreEqual(14927, ParsingPrimitives.DecodeZigZag32(WritingPrimitives.EncodeZigZag32(14927)));
             Assert.AreEqual(-3612, ParsingPrimitives.DecodeZigZag32(WritingPrimitives.EncodeZigZag32(-3612)));
         }

         [Test]
         public void RoundTripZigZag64()
         {
             Assert.AreEqual(0, ParsingPrimitives.DecodeZigZag64(WritingPrimitives.EncodeZigZag64(0)));
             Assert.AreEqual(1, ParsingPrimitives.DecodeZigZag64(WritingPrimitives.EncodeZigZag64(1)));
             Assert.AreEqual(-1, ParsingPrimitives.DecodeZigZag64(WritingPrimitives.EncodeZigZag64(-1)));
             Assert.AreEqual(14927, ParsingPrimitives.DecodeZigZag64(WritingPrimitives.EncodeZigZag64(14927)));
             Assert.AreEqual(-3612, ParsingPrimitives.DecodeZigZag64(WritingPrimitives.EncodeZigZag64(-3612)));

             Assert.AreEqual(856912304801416L,
                             ParsingPrimitives.DecodeZigZag64(WritingPrimitives.EncodeZigZag64(856912304801416L)));
             Assert.AreEqual(-75123905439571256L,
                             ParsingPrimitives.DecodeZigZag64(WritingPrimitives.EncodeZigZag64(-75123905439571256L)));
         }

         [Test]
         public void TestNegativeEnumNoTag()
         {
             Assert.AreEqual(10, CodedOutputStream.ComputeInt32Size(-2));
             Assert.AreEqual(10, CodedOutputStream.ComputeEnumSize((int) SampleEnum.NegativeValue));

             byte[] bytes = new byte[10];
             CodedOutputStream output = new CodedOutputStream(bytes);
             output.WriteEnum((int) SampleEnum.NegativeValue);

             Assert.AreEqual(0, output.SpaceLeft);
             Assert.AreEqual("FE-FF-FF-FF-FF-FF-FF-FF-FF-01", BitConverter.ToString(bytes));
         }

         [Test]
         public void TestCodedInputOutputPosition()
         {
             byte[] content = new byte[110];
             for (int i = 0; i < content.Length; i++)
                 content[i] = (byte)i;

             byte[] child = new byte[120];
             {
                 MemoryStream ms = new MemoryStream(child);
                 CodedOutputStream cout = new CodedOutputStream(ms, 20);
                 // Field 11: numeric value: 500
                 cout.WriteTag(11, WireFormat.WireType.Varint);
                 Assert.AreEqual(1, cout.Position);
                 cout.WriteInt32(500);
                 Assert.AreEqual(3, cout.Position);
                 //Field 12: length delimited 120 bytes
                 cout.WriteTag(12, WireFormat.WireType.LengthDelimited);
                 Assert.AreEqual(4, cout.Position);
                 cout.WriteBytes(ByteString.CopyFrom(content));
                 Assert.AreEqual(115, cout.Position);
                 // Field 13: fixed numeric value: 501
                 cout.WriteTag(13, WireFormat.WireType.Fixed32);
                 Assert.AreEqual(116, cout.Position);
                 cout.WriteSFixed32(501);
                 Assert.AreEqual(120, cout.Position);
                 cout.Flush();
             }

             byte[] bytes = new byte[130];
             {
                 CodedOutputStream cout = new CodedOutputStream(bytes);
                 // Field 1: numeric value: 500
                 cout.WriteTag(1, WireFormat.WireType.Varint);
                 Assert.AreEqual(1, cout.Position);
                 cout.WriteInt32(500);
                 Assert.AreEqual(3, cout.Position);
                 //Field 2: length delimited 120 bytes
                 cout.WriteTag(2, WireFormat.WireType.LengthDelimited);
                 Assert.AreEqual(4, cout.Position);
                 cout.WriteBytes(ByteString.CopyFrom(child));
                 Assert.AreEqual(125, cout.Position);
                 // Field 3: fixed numeric value: 500
                 cout.WriteTag(3, WireFormat.WireType.Fixed32);
                 Assert.AreEqual(126, cout.Position);
                 cout.WriteSFixed32(501);
                 Assert.AreEqual(130, cout.Position);
                 cout.Flush();
             }
             // Now test Input stream:
             {
                 CodedInputStream cin = new CodedInputStream(new MemoryStream(bytes), new byte[50], 0, 0, false);
                 Assert.AreEqual(0, cin.Position);
                 // Field 1:
                 uint tag = cin.ReadTag();
                 Assert.AreEqual(1, tag >> 3);
                 Assert.AreEqual(1, cin.Position);
                 Assert.AreEqual(500, cin.ReadInt32());
                 Assert.AreEqual(3, cin.Position);
                 //Field 2:
                 tag = cin.ReadTag();
                 Assert.AreEqual(2, tag >> 3);
                 Assert.AreEqual(4, cin.Position);
                 int childlen = cin.ReadLength();
                 Assert.AreEqual(120, childlen);
                 Assert.AreEqual(5, cin.Position);
                 int oldlimit = cin.PushLimit((int)childlen);
                 Assert.AreEqual(5, cin.Position);
                 // Now we are reading child message
                 {
                     // Field 11: numeric value: 500
                     tag = cin.ReadTag();
                     Assert.AreEqual(11, tag >> 3);
                     Assert.AreEqual(6, cin.Position);
                     Assert.AreEqual(500, cin.ReadInt32());
                     Assert.AreEqual(8, cin.Position);
                     //Field 12: length delimited 120 bytes
                     tag = cin.ReadTag();
                     Assert.AreEqual(12, tag >> 3);
                     Assert.AreEqual(9, cin.Position);
                     ByteString bstr = cin.ReadBytes();
                     Assert.AreEqual(110, bstr.Length);
                     Assert.AreEqual((byte) 109, bstr[109]);
                     Assert.AreEqual(120, cin.Position);
                     // Field 13: fixed numeric value: 501
                     tag = cin.ReadTag();
                     Assert.AreEqual(13, tag >> 3);
                     // ROK - Previously broken here, this returned 126 failing to account for bufferSizeAfterLimit
                     Assert.AreEqual(121, cin.Position);
                     Assert.AreEqual(501, cin.ReadSFixed32());
                     Assert.AreEqual(125, cin.Position);
                     Assert.IsTrue(cin.IsAtEnd);
                 }
                 cin.PopLimit(oldlimit);
                 Assert.AreEqual(125, cin.Position);
                 // Field 3: fixed numeric value: 501
                 tag = cin.ReadTag();
                 Assert.AreEqual(3, tag >> 3);
                 Assert.AreEqual(126, cin.Position);
                 Assert.AreEqual(501, cin.ReadSFixed32());
                 Assert.AreEqual(130, cin.Position);
                 Assert.IsTrue(cin.IsAtEnd);
             }
         }

         [Test]
         public void Dispose_DisposesUnderlyingStream()
         {
             var memoryStream = new MemoryStream();
             Assert.IsTrue(memoryStream.CanWrite);
             using (var cos = new CodedOutputStream(memoryStream))
             {
                 cos.WriteRawBytes(new byte[] {0});
                 Assert.AreEqual(0, memoryStream.Position); // Not flushed yet
             }
             Assert.AreEqual(1, memoryStream.ToArray().Length); // Flushed data from CodedOutputStream to MemoryStream
             Assert.IsFalse(memoryStream.CanWrite); // Disposed
         }

         [Test]
         public void Dispose_WithLeaveOpen()
         {
             var memoryStream = new MemoryStream();
             Assert.IsTrue(memoryStream.CanWrite);
             using (var cos = new CodedOutputStream(memoryStream, true))
             {
                 cos.WriteRawBytes(new byte[] {0});
                 Assert.AreEqual(0, memoryStream.Position); // Not flushed yet
             }
             Assert.AreEqual(1, memoryStream.Position); // Flushed data from CodedOutputStream to MemoryStream
             Assert.IsTrue(memoryStream.CanWrite); // We left the stream open
         }

         [Test]
         public void Dispose_FromByteArray()
         {
             var stream = new CodedOutputStream(new byte[10]);
             stream.Dispose();
         }

         [Test]
         public void WriteString_AsciiSmall_MaxUtf8SizeExceedsBuffer()
         {
             var buffer = new byte[5];
             var output = new CodedOutputStream(buffer);
             output.WriteString("ABC");

             output.Flush();

             // Verify written content
             var input = new CodedInputStream(buffer);
             Assert.AreEqual("ABC", input.ReadString());
         }

         [Test]
         public void WriteStringsOfDifferentSizes_Ascii()
         {
             for (int i = 1; i <= 1024; i++)
             {
                 var buffer = new byte[4096];
                 var output = new CodedOutputStream(buffer);
                 var sb = new StringBuilder();
                 for (int j = 0; j < i; j++)
                 {
                     sb.Append((j % 10).ToString()); // incrementing numbers, repeating
                 }
                 var s = sb.ToString();
                 output.WriteString(s);

                 output.Flush();

                 // Verify written content
                 var input = new CodedInputStream(buffer);
                 Assert.AreEqual(s, input.ReadString());
             }
         }

         [Test]
         public void WriteStringsOfDifferentSizes_Unicode()
         {
             for (int i = 1; i <= 1024; i++)
             {
                 var buffer = new byte[4096];
                 var output = new CodedOutputStream(buffer);
                 var sb = new StringBuilder();
                 for (int j = 0; j < i; j++)
                 {
                     char c = (char)((j % 10) + 10112);
                     sb.Append(c.ToString()); // incrementing unicode numbers, repeating
                 }
                 var s = sb.ToString();
                 output.WriteString(s);

                 output.Flush();

                 // Verify written content
                 var input = new CodedInputStream(buffer);

                 Assert.AreEqual(s, input.ReadString());
             }
         }
     }
 }
	#region Copyright notice and license
	// Protocol Buffers - Google's data interchange format
	// Copyright 2008 Google Inc. All rights reserved.
	// https://developers.google.com/protocol-buffers/
	//
	// 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.IO;
	using Google.Protobuf.TestProtos;
	using Google.Protobuf.Buffers;
	using NUnit.Framework;
	using System.Text;

	namespace Google.Protobuf
	{
	public class CodedOutputStreamTest
	{
	/// <summary>
	/// Writes the given value using WriteRawVarint32() and WriteRawVarint64() and
	/// checks that the result matches the given bytes
	/// </summary>
	private static void AssertWriteVarint(byte[] data, ulong value)
	{
	// Only do 32-bit write if the value fits in 32 bits.
	if ((value >> 32) == 0)
	{
	// CodedOutputStream
	MemoryStream rawOutput = new MemoryStream();
	CodedOutputStream output = new CodedOutputStream(rawOutput);
	output.WriteRawVarint32((uint) value);
	output.Flush();
	Assert.AreEqual(data, rawOutput.ToArray());

	// IBufferWriter
	var bufferWriter = new TestArrayBufferWriter<byte>();
	WriteContext.Initialize(bufferWriter, out WriteContext ctx);
	ctx.WriteUInt32((uint) value);
	ctx.Flush();
	Assert.AreEqual(data, bufferWriter.WrittenSpan.ToArray());

	// Also try computing size.
	Assert.AreEqual(data.Length, CodedOutputStream.ComputeRawVarint32Size((uint) value));
	}

	{
	// CodedOutputStream
	MemoryStream rawOutput = new MemoryStream();
	CodedOutputStream output = new CodedOutputStream(rawOutput);
	output.WriteRawVarint64(value);
	output.Flush();
	Assert.AreEqual(data, rawOutput.ToArray());

	// IBufferWriter
	var bufferWriter = new TestArrayBufferWriter<byte>();
	WriteContext.Initialize(bufferWriter, out WriteContext ctx);
	ctx.WriteUInt64(value);
	ctx.Flush();
	Assert.AreEqual(data, bufferWriter.WrittenSpan.ToArray());

	// Also try computing size.
	Assert.AreEqual(data.Length, CodedOutputStream.ComputeRawVarint64Size(value));
	}

	// Try different buffer sizes.
	for (int bufferSize = 1; bufferSize <= 16; bufferSize *= 2)
	{
	// Only do 32-bit write if the value fits in 32 bits.
	if ((value >> 32) == 0)
	{
	MemoryStream rawOutput = new MemoryStream();
	CodedOutputStream output =
	new CodedOutputStream(rawOutput, bufferSize);
	output.WriteRawVarint32((uint) value);
	output.Flush();
	Assert.AreEqual(data, rawOutput.ToArray());

	var bufferWriter = new TestArrayBufferWriter<byte>();
	bufferWriter.MaxGrowBy = bufferSize;
	WriteContext.Initialize(bufferWriter, out WriteContext ctx);
	ctx.WriteUInt32((uint) value);
	ctx.Flush();
	Assert.AreEqual(data, bufferWriter.WrittenSpan.ToArray());
	}

	{
	MemoryStream rawOutput = new MemoryStream();
	CodedOutputStream output = new CodedOutputStream(rawOutput, bufferSize);
	output.WriteRawVarint64(value);
	output.Flush();
	Assert.AreEqual(data, rawOutput.ToArray());

	var bufferWriter = new TestArrayBufferWriter<byte>();
	bufferWriter.MaxGrowBy = bufferSize;
	WriteContext.Initialize(bufferWriter, out WriteContext ctx);
	ctx.WriteUInt64(value);
	ctx.Flush();
	Assert.AreEqual(data, bufferWriter.WrittenSpan.ToArray());
	}

	}
	}

	/// <summary>
	/// Tests WriteRawVarint32() and WriteRawVarint64()
	/// </summary>
	[Test]
	public void WriteVarint()
	{
	AssertWriteVarint(new byte[] {0x00}, 0);
	AssertWriteVarint(new byte[] {0x01}, 1);
	AssertWriteVarint(new byte[] {0x7f}, 127);
	// 14882
	AssertWriteVarint(new byte[] {0xa2, 0x74}, (0x22 << 0) \| (0x74 << 7));
	// 2961488830
	AssertWriteVarint(new byte[] {0xbe, 0xf7, 0x92, 0x84, 0x0b},
	(0x3e << 0) \| (0x77 << 7) \| (0x12 << 14) \| (0x04 << 21) \|
	(0x0bL << 28));

	// 64-bit
	// 7256456126
	AssertWriteVarint(new byte[] {0xbe, 0xf7, 0x92, 0x84, 0x1b},
	(0x3e << 0) \| (0x77 << 7) \| (0x12 << 14) \| (0x04 << 21) \|
	(0x1bL << 28));
	// 41256202580718336
	AssertWriteVarint(
	new byte[] {0x80, 0xe6, 0xeb, 0x9c, 0xc3, 0xc9, 0xa4, 0x49},
	(0x00 << 0) \| (0x66 << 7) \| (0x6b << 14) \| (0x1c << 21) \|
	(0x43UL << 28) \| (0x49L << 35) \| (0x24UL << 42) \| (0x49UL << 49));
	// 11964378330978735131
	AssertWriteVarint(
	new byte[] {0x9b, 0xa8, 0xf9, 0xc2, 0xbb, 0xd6, 0x80, 0x85, 0xa6, 0x01},
	unchecked((ulong)
	((0x1b << 0) \| (0x28 << 7) \| (0x79 << 14) \| (0x42 << 21) \|
	(0x3bL << 28) \| (0x56L << 35) \| (0x00L << 42) \|
	(0x05L << 49) \| (0x26L << 56) \| (0x01L << 63))));
	}

	/// <summary>
	/// Parses the given bytes using WriteRawLittleEndian32() and checks
	/// that the result matches the given value.
	/// </summary>
	private static void AssertWriteLittleEndian32(byte[] data, uint value)
	{
	{
	var rawOutput = new MemoryStream();
	var output = new CodedOutputStream(rawOutput);
	output.WriteRawLittleEndian32(value);
	output.Flush();
	Assert.AreEqual(data, rawOutput.ToArray());

	var bufferWriter = new TestArrayBufferWriter<byte>();
	WriteContext.Initialize(bufferWriter, out WriteContext ctx);
	ctx.WriteFixed32(value);
	ctx.Flush();
	Assert.AreEqual(data, bufferWriter.WrittenSpan.ToArray());
	}

	// Try different buffer sizes.
	for (int bufferSize = 1; bufferSize <= 16; bufferSize *= 2)
	{
	var rawOutput = new MemoryStream();
	var output = new CodedOutputStream(rawOutput, bufferSize);
	output.WriteRawLittleEndian32(value);
	output.Flush();
	Assert.AreEqual(data, rawOutput.ToArray());

	var bufferWriter = new TestArrayBufferWriter<byte>();
	bufferWriter.MaxGrowBy = bufferSize;
	WriteContext.Initialize(bufferWriter, out WriteContext ctx);
	ctx.WriteFixed32(value);
	ctx.Flush();
	Assert.AreEqual(data, bufferWriter.WrittenSpan.ToArray());
	}
	}

	/// <summary>
	/// Parses the given bytes using WriteRawLittleEndian64() and checks
	/// that the result matches the given value.
	/// </summary>
	private static void AssertWriteLittleEndian64(byte[] data, ulong value)
	{
	{
	var rawOutput = new MemoryStream();
	var output = new CodedOutputStream(rawOutput);
	output.WriteRawLittleEndian64(value);
	output.Flush();
	Assert.AreEqual(data, rawOutput.ToArray());

	var bufferWriter = new TestArrayBufferWriter<byte>();
	WriteContext.Initialize(bufferWriter, out WriteContext ctx);
	ctx.WriteFixed64(value);
	ctx.Flush();
	Assert.AreEqual(data, bufferWriter.WrittenSpan.ToArray());
	}

	// Try different block sizes.
	for (int blockSize = 1; blockSize <= 16; blockSize *= 2)
	{
	var rawOutput = new MemoryStream();
	var output = new CodedOutputStream(rawOutput, blockSize);
	output.WriteRawLittleEndian64(value);
	output.Flush();
	Assert.AreEqual(data, rawOutput.ToArray());

	var bufferWriter = new TestArrayBufferWriter<byte>();
	bufferWriter.MaxGrowBy = blockSize;
	WriteContext.Initialize(bufferWriter, out WriteContext ctx);
	ctx.WriteFixed64(value);
	ctx.Flush();
	Assert.AreEqual(data, bufferWriter.WrittenSpan.ToArray());
	}
	}

	/// <summary>
	/// Tests writeRawLittleEndian32() and writeRawLittleEndian64().
	/// </summary>
	[Test]
	public void WriteLittleEndian()
	{
	AssertWriteLittleEndian32(new byte[] {0x78, 0x56, 0x34, 0x12}, 0x12345678);
	AssertWriteLittleEndian32(new byte[] {0xf0, 0xde, 0xbc, 0x9a}, 0x9abcdef0);

	AssertWriteLittleEndian64(
	new byte[] {0xf0, 0xde, 0xbc, 0x9a, 0x78, 0x56, 0x34, 0x12},
	0x123456789abcdef0L);
	AssertWriteLittleEndian64(
	new byte[] {0x78, 0x56, 0x34, 0x12, 0xf0, 0xde, 0xbc, 0x9a},
	0x9abcdef012345678UL);
	}

	[Test]
	public void WriteWholeMessage_VaryingBlockSizes()
	{
	TestAllTypes message = SampleMessages.CreateFullTestAllTypes();

	byte[] rawBytes = message.ToByteArray();

	// Try different block sizes.
	for (int blockSize = 1; blockSize < 256; blockSize *= 2)
	{
	MemoryStream rawOutput = new MemoryStream();
	CodedOutputStream output = new CodedOutputStream(rawOutput, blockSize);
	message.WriteTo(output);
	output.Flush();
	Assert.AreEqual(rawBytes, rawOutput.ToArray());

	var bufferWriter = new TestArrayBufferWriter<byte>();
	bufferWriter.MaxGrowBy = blockSize;
	message.WriteTo(bufferWriter);
	Assert.AreEqual(rawBytes, bufferWriter.WrittenSpan.ToArray());
	}
	}

	[Test]
	public void WriteContext_WritesWithFlushes()
	{
	TestAllTypes message = SampleMessages.CreateFullTestAllTypes();

	MemoryStream expectedOutput = new MemoryStream();
	CodedOutputStream output = new CodedOutputStream(expectedOutput);
	output.WriteMessage(message);
	output.Flush();
	byte[] expectedBytes1 = expectedOutput.ToArray();

	output.WriteMessage(message);
	output.Flush();
	byte[] expectedBytes2 = expectedOutput.ToArray();

	var bufferWriter = new TestArrayBufferWriter<byte>();
	WriteContext.Initialize(bufferWriter, out WriteContext ctx);
	ctx.WriteMessage(message);
	ctx.Flush();
	Assert.AreEqual(expectedBytes1, bufferWriter.WrittenSpan.ToArray());

	ctx.WriteMessage(message);
	ctx.Flush();
	Assert.AreEqual(expectedBytes2, bufferWriter.WrittenSpan.ToArray());
	}

	[Test]
	public void EncodeZigZag32()
	{
	Assert.AreEqual(0u, WritingPrimitives.EncodeZigZag32(0));
	Assert.AreEqual(1u, WritingPrimitives.EncodeZigZag32(-1));
	Assert.AreEqual(2u, WritingPrimitives.EncodeZigZag32(1));
	Assert.AreEqual(3u, WritingPrimitives.EncodeZigZag32(-2));
	Assert.AreEqual(0x7FFFFFFEu, WritingPrimitives.EncodeZigZag32(0x3FFFFFFF));
	Assert.AreEqual(0x7FFFFFFFu, WritingPrimitives.EncodeZigZag32(unchecked((int) 0xC0000000)));
	Assert.AreEqual(0xFFFFFFFEu, WritingPrimitives.EncodeZigZag32(0x7FFFFFFF));
	Assert.AreEqual(0xFFFFFFFFu, WritingPrimitives.EncodeZigZag32(unchecked((int) 0x80000000)));
	}

	[Test]
	public void EncodeZigZag64()
	{
	Assert.AreEqual(0u, WritingPrimitives.EncodeZigZag64(0));
	Assert.AreEqual(1u, WritingPrimitives.EncodeZigZag64(-1));
	Assert.AreEqual(2u, WritingPrimitives.EncodeZigZag64(1));
	Assert.AreEqual(3u, WritingPrimitives.EncodeZigZag64(-2));
	Assert.AreEqual(0x000000007FFFFFFEuL,
	WritingPrimitives.EncodeZigZag64(unchecked((long) 0x000000003FFFFFFFUL)));
	Assert.AreEqual(0x000000007FFFFFFFuL,
	WritingPrimitives.EncodeZigZag64(unchecked((long) 0xFFFFFFFFC0000000UL)));
	Assert.AreEqual(0x00000000FFFFFFFEuL,
	WritingPrimitives.EncodeZigZag64(unchecked((long) 0x000000007FFFFFFFUL)));
	Assert.AreEqual(0x00000000FFFFFFFFuL,
	WritingPrimitives.EncodeZigZag64(unchecked((long) 0xFFFFFFFF80000000UL)));
	Assert.AreEqual(0xFFFFFFFFFFFFFFFEL,
	WritingPrimitives.EncodeZigZag64(unchecked((long) 0x7FFFFFFFFFFFFFFFUL)));
	Assert.AreEqual(0xFFFFFFFFFFFFFFFFL,
	WritingPrimitives.EncodeZigZag64(unchecked((long) 0x8000000000000000UL)));
	}

	[Test]
	public void RoundTripZigZag32()
	{
	// Some easier-to-verify round-trip tests. The inputs (other than 0, 1, -1)
	// were chosen semi-randomly via keyboard bashing.
	Assert.AreEqual(0, ParsingPrimitives.DecodeZigZag32(WritingPrimitives.EncodeZigZag32(0)));
	Assert.AreEqual(1, ParsingPrimitives.DecodeZigZag32(WritingPrimitives.EncodeZigZag32(1)));
	Assert.AreEqual(-1, ParsingPrimitives.DecodeZigZag32(WritingPrimitives.EncodeZigZag32(-1)));
	Assert.AreEqual(14927, ParsingPrimitives.DecodeZigZag32(WritingPrimitives.EncodeZigZag32(14927)));
	Assert.AreEqual(-3612, ParsingPrimitives.DecodeZigZag32(WritingPrimitives.EncodeZigZag32(-3612)));
	}

	[Test]
	public void RoundTripZigZag64()
	{
	Assert.AreEqual(0, ParsingPrimitives.DecodeZigZag64(WritingPrimitives.EncodeZigZag64(0)));
	Assert.AreEqual(1, ParsingPrimitives.DecodeZigZag64(WritingPrimitives.EncodeZigZag64(1)));
	Assert.AreEqual(-1, ParsingPrimitives.DecodeZigZag64(WritingPrimitives.EncodeZigZag64(-1)));
	Assert.AreEqual(14927, ParsingPrimitives.DecodeZigZag64(WritingPrimitives.EncodeZigZag64(14927)));
	Assert.AreEqual(-3612, ParsingPrimitives.DecodeZigZag64(WritingPrimitives.EncodeZigZag64(-3612)));

	Assert.AreEqual(856912304801416L,
	ParsingPrimitives.DecodeZigZag64(WritingPrimitives.EncodeZigZag64(856912304801416L)));
	Assert.AreEqual(-75123905439571256L,
	ParsingPrimitives.DecodeZigZag64(WritingPrimitives.EncodeZigZag64(-75123905439571256L)));
	}

	[Test]
	public void TestNegativeEnumNoTag()
	{
	Assert.AreEqual(10, CodedOutputStream.ComputeInt32Size(-2));
	Assert.AreEqual(10, CodedOutputStream.ComputeEnumSize((int) SampleEnum.NegativeValue));

	byte[] bytes = new byte[10];
	CodedOutputStream output = new CodedOutputStream(bytes);
	output.WriteEnum((int) SampleEnum.NegativeValue);

	Assert.AreEqual(0, output.SpaceLeft);
	Assert.AreEqual("FE-FF-FF-FF-FF-FF-FF-FF-FF-01", BitConverter.ToString(bytes));
	}

	[Test]
	public void TestCodedInputOutputPosition()
	{
	byte[] content = new byte[110];
	for (int i = 0; i < content.Length; i++)
	content[i] = (byte)i;

	byte[] child = new byte[120];
	{
	MemoryStream ms = new MemoryStream(child);
	CodedOutputStream cout = new CodedOutputStream(ms, 20);
	// Field 11: numeric value: 500
	cout.WriteTag(11, WireFormat.WireType.Varint);
	Assert.AreEqual(1, cout.Position);
	cout.WriteInt32(500);
	Assert.AreEqual(3, cout.Position);
	//Field 12: length delimited 120 bytes
	cout.WriteTag(12, WireFormat.WireType.LengthDelimited);
	Assert.AreEqual(4, cout.Position);
	cout.WriteBytes(ByteString.CopyFrom(content));
	Assert.AreEqual(115, cout.Position);
	// Field 13: fixed numeric value: 501
	cout.WriteTag(13, WireFormat.WireType.Fixed32);
	Assert.AreEqual(116, cout.Position);
	cout.WriteSFixed32(501);
	Assert.AreEqual(120, cout.Position);
	cout.Flush();
	}

	byte[] bytes = new byte[130];
	{
	CodedOutputStream cout = new CodedOutputStream(bytes);
	// Field 1: numeric value: 500
	cout.WriteTag(1, WireFormat.WireType.Varint);
	Assert.AreEqual(1, cout.Position);
	cout.WriteInt32(500);
	Assert.AreEqual(3, cout.Position);
	//Field 2: length delimited 120 bytes
	cout.WriteTag(2, WireFormat.WireType.LengthDelimited);
	Assert.AreEqual(4, cout.Position);
	cout.WriteBytes(ByteString.CopyFrom(child));
	Assert.AreEqual(125, cout.Position);
	// Field 3: fixed numeric value: 500
	cout.WriteTag(3, WireFormat.WireType.Fixed32);
	Assert.AreEqual(126, cout.Position);
	cout.WriteSFixed32(501);
	Assert.AreEqual(130, cout.Position);
	cout.Flush();
	}
	// Now test Input stream:
	{
	CodedInputStream cin = new CodedInputStream(new MemoryStream(bytes), new byte[50], 0, 0, false);
	Assert.AreEqual(0, cin.Position);
	// Field 1:
	uint tag = cin.ReadTag();
	Assert.AreEqual(1, tag >> 3);
	Assert.AreEqual(1, cin.Position);
	Assert.AreEqual(500, cin.ReadInt32());
	Assert.AreEqual(3, cin.Position);
	//Field 2:
	tag = cin.ReadTag();
	Assert.AreEqual(2, tag >> 3);
	Assert.AreEqual(4, cin.Position);
	int childlen = cin.ReadLength();
	Assert.AreEqual(120, childlen);
	Assert.AreEqual(5, cin.Position);
	int oldlimit = cin.PushLimit((int)childlen);
	Assert.AreEqual(5, cin.Position);
	// Now we are reading child message
	{
	// Field 11: numeric value: 500
	tag = cin.ReadTag();
	Assert.AreEqual(11, tag >> 3);
	Assert.AreEqual(6, cin.Position);
	Assert.AreEqual(500, cin.ReadInt32());
	Assert.AreEqual(8, cin.Position);
	//Field 12: length delimited 120 bytes
	tag = cin.ReadTag();
	Assert.AreEqual(12, tag >> 3);
	Assert.AreEqual(9, cin.Position);
	ByteString bstr = cin.ReadBytes();
	Assert.AreEqual(110, bstr.Length);
	Assert.AreEqual((byte) 109, bstr[109]);
	Assert.AreEqual(120, cin.Position);
	// Field 13: fixed numeric value: 501
	tag = cin.ReadTag();
	Assert.AreEqual(13, tag >> 3);
	// ROK - Previously broken here, this returned 126 failing to account for bufferSizeAfterLimit
	Assert.AreEqual(121, cin.Position);
	Assert.AreEqual(501, cin.ReadSFixed32());
	Assert.AreEqual(125, cin.Position);
	Assert.IsTrue(cin.IsAtEnd);
	}
	cin.PopLimit(oldlimit);
	Assert.AreEqual(125, cin.Position);
	// Field 3: fixed numeric value: 501
	tag = cin.ReadTag();
	Assert.AreEqual(3, tag >> 3);
	Assert.AreEqual(126, cin.Position);
	Assert.AreEqual(501, cin.ReadSFixed32());
	Assert.AreEqual(130, cin.Position);
	Assert.IsTrue(cin.IsAtEnd);
	}
	}

	[Test]
	public void Dispose_DisposesUnderlyingStream()
	{
	var memoryStream = new MemoryStream();
	Assert.IsTrue(memoryStream.CanWrite);
	using (var cos = new CodedOutputStream(memoryStream))
	{
	cos.WriteRawBytes(new byte[] {0});
	Assert.AreEqual(0, memoryStream.Position); // Not flushed yet
	}
	Assert.AreEqual(1, memoryStream.ToArray().Length); // Flushed data from CodedOutputStream to MemoryStream
	Assert.IsFalse(memoryStream.CanWrite); // Disposed
	}

	[Test]
	public void Dispose_WithLeaveOpen()
	{
	var memoryStream = new MemoryStream();
	Assert.IsTrue(memoryStream.CanWrite);
	using (var cos = new CodedOutputStream(memoryStream, true))
	{
	cos.WriteRawBytes(new byte[] {0});
	Assert.AreEqual(0, memoryStream.Position); // Not flushed yet
	}
	Assert.AreEqual(1, memoryStream.Position); // Flushed data from CodedOutputStream to MemoryStream
	Assert.IsTrue(memoryStream.CanWrite); // We left the stream open
	}

	[Test]
	public void Dispose_FromByteArray()
	{
	var stream = new CodedOutputStream(new byte[10]);
	stream.Dispose();
	}

	[Test]
	public void WriteString_AsciiSmall_MaxUtf8SizeExceedsBuffer()
	{
	var buffer = new byte[5];
	var output = new CodedOutputStream(buffer);
	output.WriteString("ABC");

	output.Flush();

	// Verify written content
	var input = new CodedInputStream(buffer);
	Assert.AreEqual("ABC", input.ReadString());
	}

	[Test]
	public void WriteStringsOfDifferentSizes_Ascii()
	{
	for (int i = 1; i <= 1024; i++)
	{
	var buffer = new byte[4096];
	var output = new CodedOutputStream(buffer);
	var sb = new StringBuilder();
	for (int j = 0; j < i; j++)
	{
	sb.Append((j % 10).ToString()); // incrementing numbers, repeating
	}
	var s = sb.ToString();
	output.WriteString(s);

	output.Flush();

	// Verify written content
	var input = new CodedInputStream(buffer);
	Assert.AreEqual(s, input.ReadString());
	}
	}

	[Test]
	public void WriteStringsOfDifferentSizes_Unicode()
	{
	for (int i = 1; i <= 1024; i++)
	{
	var buffer = new byte[4096];
	var output = new CodedOutputStream(buffer);
	var sb = new StringBuilder();
	for (int j = 0; j < i; j++)
	{
	char c = (char)((j % 10) + 10112);
	sb.Append(c.ToString()); // incrementing unicode numbers, repeating
	}
	var s = sb.ToString();
	output.WriteString(s);

	output.Flush();

	// Verify written content
	var input = new CodedInputStream(buffer);

	Assert.AreEqual(s, input.ReadString());
	}
	}
	}
	}