Update to C# 10 and upgrade code style

Makefile.am

@@ -92,6 +92,7 @@ csharp_EXTRA_DIST=                                                           \
   csharp/src/AddressBook/ListPeople.cs                                       \
   csharp/src/AddressBook/Program.cs                                          \
   csharp/src/AddressBook/SampleUsage.cs                                      \
+  csharp/src/Directory.Build.props                                           \
   csharp/src/Google.Protobuf.Benchmarks/BenchmarkDatasetConfig.cs            \
   csharp/src/Google.Protobuf.Benchmarks/BenchmarkMessage1Proto3.cs           \
   csharp/src/Google.Protobuf.Benchmarks/Benchmarks.cs                        \

csharp/README.md

@@ -23,6 +23,7 @@ The runtime library is built as a portable class library, supporting:
 - Windows Phone Silverlight 8
 - Windows Phone 8.1
 - .NET Core
+- .NET 5
 
 You should be able to use Protocol Buffers in Visual Studio 2012 and
 all later versions. This includes all code generated by `protoc`,
@@ -31,15 +32,15 @@ which only uses features from C# 3 and earlier.
 Building
 ========
 
-Open the `src/Google.Protobuf.sln` solution in Visual Studio 2017 or
+Open the `src/Google.Protobuf.sln` solution in Visual Studio 2022 or
 later.
 
 Although *users* of this project are only expected to have Visual
 Studio 2012 or later, *developers* of the library are required to
-have Visual Studio 2017 or later, as the library uses C# 6 features
-in its implementation, as well as the new Visual Studio 2017 csproj
-format. These features have no impact when using the compiled code -
-they're only relevant when building the `Google.Protobuf` assembly.
+have Visual Studio 2022 or later, as the library uses C# 10 features
+in its implementation and runs tests under .NET 6. These features
+have no impact when using the compiled code - they're only relevant
+when building the `Google.Protobuf` assembly.
 
 In order to run and debug the AddressBook example in the IDE, you must
 install the optional component, ".Net Core 1.0 - 1.1 development tools

csharp/compatibility_tests/v3.0.0/src/Google.Protobuf.Test/Google.Protobuf.Test.csproj

@@ -6,6 +6,7 @@
     <AssemblyOriginatorKeyFile>../../keys/Google.Protobuf.snk</AssemblyOriginatorKeyFile>
     <SignAssembly>true</SignAssembly>
     <IsPackable>False</IsPackable>
+    <LangVersion>8.0</LangVersion>
   </PropertyGroup>
 
   <ItemGroup>

csharp/src/AddressBook/AddPerson.cs

@@ -107,10 +107,8 @@ public static int Main(string[] args)
 
             if (File.Exists(args[0]))
             {
-                using (Stream file = File.OpenRead(args[0]))
-                {
-                    addressBook = AddressBook.Parser.ParseFrom(file);
-                }
+                using Stream file = File.OpenRead(args[0]);
+                addressBook = AddressBook.Parser.ParseFrom(file);
             }
             else
             {

csharp/src/Directory.Build.props

@@ -0,0 +1,7 @@
+<Project>
+
+  <PropertyGroup>
+    <LangVersion>10.0</LangVersion>
+  </PropertyGroup>
+
+</Project>

csharp/src/Google.Protobuf.Benchmarks/BenchmarkDatasetConfig.cs

@@ -72,16 +72,14 @@ public BenchmarkDatasetConfig(string resource, string shortName = null)
 
         private static byte[] LoadData(string resource)
         {
-            using (var stream = typeof(GoogleMessageBenchmark).Assembly.GetManifestResourceStream($"Google.Protobuf.Benchmarks.{resource}"))
+            using var stream = typeof(GoogleMessageBenchmark).Assembly.GetManifestResourceStream($"Google.Protobuf.Benchmarks.{resource}");
+            if (stream == null)
             {
-                if (stream == null)
-                {
-                    throw new ArgumentException($"Unable to load embedded resource {resource}");
-                }
-                var copy = new MemoryStream();
-                stream.CopyTo(copy);
-                return copy.ToArray();
+                throw new ArgumentException($"Unable to load embedded resource {resource}");
             }
+            var copy = new MemoryStream();
+            stream.CopyTo(copy);
+            return copy.ToArray();
         }
 
         public override string ToString() => Name;

csharp/src/Google.Protobuf.Benchmarks/ParseMessagesBenchmark.cs

@@ -49,10 +49,10 @@ public class ParseMessagesBenchmark
     {
         const int MaxMessages = 100;
 
-        SubTest manyWrapperFieldsTest = new SubTest(CreateManyWrapperFieldsMessage(), ManyWrapperFieldsMessage.Parser, () => new ManyWrapperFieldsMessage(), MaxMessages);
-        SubTest manyPrimitiveFieldsTest = new SubTest(CreateManyPrimitiveFieldsMessage(), ManyPrimitiveFieldsMessage.Parser, () => new ManyPrimitiveFieldsMessage(), MaxMessages);
-        SubTest repeatedFieldTest = new SubTest(CreateRepeatedFieldMessage(), GoogleMessage1.Parser, () => new GoogleMessage1(), MaxMessages);
-        SubTest emptyMessageTest = new SubTest(new Empty(), Empty.Parser, () => new Empty(), MaxMessages);
+        private readonly SubTest manyWrapperFieldsTest = new(CreateManyWrapperFieldsMessage(), ManyWrapperFieldsMessage.Parser, () => new ManyWrapperFieldsMessage(), MaxMessages);
+        private readonly SubTest manyPrimitiveFieldsTest = new(CreateManyPrimitiveFieldsMessage(), ManyPrimitiveFieldsMessage.Parser, () => new ManyPrimitiveFieldsMessage(), MaxMessages);
+        private readonly SubTest repeatedFieldTest = new(CreateRepeatedFieldMessage(), GoogleMessage1.Parser, () => new GoogleMessage1(), MaxMessages);
+        private readonly SubTest emptyMessageTest = new(new Empty(), Empty.Parser, () => new Empty(), MaxMessages);
 
         public IEnumerable<int> MessageCountValues => new[] { 10, 100 };
 
@@ -204,8 +204,8 @@ private class SubTest
             private readonly byte[] data;
             private readonly byte[] multipleMessagesData;
 
-            private ReadOnlySequence<byte> dataSequence;
-            private ReadOnlySequence<byte> multipleMessagesDataSequence;
+            private readonly ReadOnlySequence<byte> dataSequence;
+            private readonly ReadOnlySequence<byte> multipleMessagesDataSequence;
 
             public SubTest(IMessage message, MessageParser parser, Func<IMessage> factory, int maxMessageCount)
             {

csharp/src/Google.Protobuf.Benchmarks/ParseRawPrimitivesBenchmark.cs

@@ -418,7 +418,7 @@ private static byte[] CreateBufferWithRandomDoubles(Random random, int valueCoun
         private static byte[] CreateBufferWithRandomData(Random random, int valueCount, int encodedSize, int paddingValueCount)
         {
             int bufferSize = (valueCount + paddingValueCount) * encodedSize;
-            byte[] buffer = new byte[bufferSize];
+            var buffer = new byte[bufferSize];
             random.NextBytes(buffer);
             return buffer;
         }

csharp/src/Google.Protobuf.Benchmarks/Program.cs

@@ -44,6 +44,4 @@ public static void Main(string[] args)
             BenchmarkSwitcher.FromAssembly(typeof(Program).Assembly).Run(args);
         }
     }
-
-
 }

csharp/src/Google.Protobuf.Benchmarks/WriteRawPrimitivesBenchmark.cs

@@ -32,10 +32,7 @@
 
 using BenchmarkDotNet.Attributes;
 using System;
-using System.Buffers.Binary;
 using System.Collections.Generic;
-using System.IO;
-using System.Buffers;
 using System.Text;
 
 namespace Google.Protobuf.Benchmarks

csharp/src/Google.Protobuf.Conformance/Program.cs

@@ -43,7 +43,7 @@ namespace Google.Protobuf.Conformance
     /// </summary>
     class Program
     {
-        private static void Main(string[] args)
+        private static void Main()
         {
             // This way we get the binary streams instead of readers/writers.
             var input = new BinaryReader(Console.OpenStandardInput());
@@ -100,32 +100,22 @@ private static ConformanceResponse PerformRequest(ConformanceRequest request, Ty
                             return new ConformanceResponse { Skipped = "CSharp doesn't support skipping unknown fields in json parsing." };
                         }
                         var parser = new JsonParser(new JsonParser.Settings(20, typeRegistry));
-                        switch (request.MessageType)
+                        message = request.MessageType switch
                         {
-                            case "protobuf_test_messages.proto3.TestAllTypesProto3":
-                                message = parser.Parse<ProtobufTestMessages.Proto3.TestAllTypesProto3>(request.JsonPayload);
-                                break;
-                            case "protobuf_test_messages.proto2.TestAllTypesProto2":
-                                message = parser.Parse<ProtobufTestMessages.Proto2.TestAllTypesProto2>(request.JsonPayload);
-                                break;
-                            default:
-                                throw new Exception($" Protobuf request doesn't have specific payload type ({request.MessageType})");
-                        }
+                            "protobuf_test_messages.proto3.TestAllTypesProto3" => parser.Parse<ProtobufTestMessages.Proto3.TestAllTypesProto3>(request.JsonPayload),
+                            "protobuf_test_messages.proto2.TestAllTypesProto2" => parser.Parse<ProtobufTestMessages.Proto2.TestAllTypesProto2>(request.JsonPayload),
+                            _ => throw new Exception($" Protobuf request doesn't have specific payload type ({request.MessageType})"),
+                        };
                         break;
                     case ConformanceRequest.PayloadOneofCase.ProtobufPayload:
-                        switch (request.MessageType)
+                        message = request.MessageType switch
                         {
-                            case "protobuf_test_messages.proto3.TestAllTypesProto3":
-                                message = ProtobufTestMessages.Proto3.TestAllTypesProto3.Parser.ParseFrom(request.ProtobufPayload);
-                                break;
-                            case "protobuf_test_messages.proto2.TestAllTypesProto2":
-                                message = ProtobufTestMessages.Proto2.TestAllTypesProto2.Parser
-                                    .WithExtensionRegistry(proto2ExtensionRegistry)
-                                    .ParseFrom(request.ProtobufPayload);
-                                break;
-                            default:
-                                throw new Exception($" Protobuf request doesn't have specific payload type ({request.MessageType})");
-                        }
+                            "protobuf_test_messages.proto3.TestAllTypesProto3" => ProtobufTestMessages.Proto3.TestAllTypesProto3.Parser.ParseFrom(request.ProtobufPayload),
+                            "protobuf_test_messages.proto2.TestAllTypesProto2" => ProtobufTestMessages.Proto2.TestAllTypesProto2.Parser
+                                                                .WithExtensionRegistry(proto2ExtensionRegistry)
+                                                                .ParseFrom(request.ProtobufPayload),
+                            _ => throw new Exception($" Protobuf request doesn't have specific payload type ({request.MessageType})"),
+                        };
                         break;
 					case ConformanceRequest.PayloadOneofCase.TextPayload:
 						return new ConformanceResponse { Skipped = "CSharp doesn't support text format" };

csharp/src/Google.Protobuf.Test.TestProtos/Google.Protobuf.Test.TestProtos.csproj

@@ -7,7 +7,7 @@
   -->
   <PropertyGroup>
     <TargetFrameworks>net462;netstandard1.1;netstandard2.0</TargetFrameworks>
-    <LangVersion>3.0</LangVersion>
+    <LangVersion>10.0</LangVersion>
     <AssemblyOriginatorKeyFile>../../keys/Google.Protobuf.snk</AssemblyOriginatorKeyFile>
     <SignAssembly>true</SignAssembly>
     <IsPackable>False</IsPackable>

csharp/src/Google.Protobuf.Test/ByteStringTest.cs

@@ -70,7 +70,7 @@ public void Equality()
             Assert.IsFalse(b1 != b1);
             Assert.IsFalse(b1 != b2);
             Assert.IsTrue(ByteString.Empty == ByteString.Empty);
-#pragma warning disable 1718
+#pragma warning restore 1718
             Assert.IsTrue(b1 != b3);
             Assert.IsTrue(b1 != b4);
             Assert.IsTrue(b1 != null);
@@ -276,12 +276,9 @@ public void ToString_Stackalloc()
             Span<byte> s = stackalloc byte[data.Length];
             data.CopyTo(s);
 
-            using (UnmanagedMemoryManager<byte> manager = new UnmanagedMemoryManager<byte>(s))
-            {
-                ByteString bs = ByteString.AttachBytes(manager.Memory);
-
-                Assert.AreEqual("Hello world", bs.ToString(Encoding.UTF8));
-            }
+            using var manager = new UnmanagedMemoryManager<byte>(s);
+            ByteString bs = ByteString.AttachBytes(manager.Memory);
+            Assert.AreEqual("Hello world", bs.ToString(Encoding.UTF8));
         }
 
         [Test]
@@ -315,12 +312,9 @@ public void ToBase64_Stackalloc()
             Span<byte> s = stackalloc byte[data.Length];
             data.CopyTo(s);
 
-            using (UnmanagedMemoryManager<byte> manager = new UnmanagedMemoryManager<byte>(s))
-            {
-                ByteString bs = ByteString.AttachBytes(manager.Memory);
-
-                Assert.AreEqual("SGVsbG8gd29ybGQ=", bs.ToBase64());
-            }
+            using var manager = new UnmanagedMemoryManager<byte>(s);
+            ByteString bs = ByteString.AttachBytes(manager.Memory);
+            Assert.AreEqual("SGVsbG8gd29ybGQ=", bs.ToBase64());
         }
 
         [Test]

csharp/src/Google.Protobuf.Test/CodedInputStreamTest.cs

@@ -563,8 +563,8 @@ public void ReadGroup_WrongEndGroupTag()
             int groupFieldNumber = Proto2.TestAllTypes.OptionalGroupFieldNumber;
 
             // write Proto2.TestAllTypes with "optional_group" set, but use wrong EndGroup closing tag
-            MemoryStream ms = new MemoryStream();
-            CodedOutputStream output = new CodedOutputStream(ms);
+            var ms = new MemoryStream();
+            var output = new CodedOutputStream(ms);
             output.WriteTag(WireFormat.MakeTag(groupFieldNumber, WireFormat.WireType.StartGroup));
             output.WriteGroup(new Proto2.TestAllTypes.Types.OptionalGroup { A = 12345 });
             // end group with different field number
@@ -578,8 +578,8 @@ public void ReadGroup_WrongEndGroupTag()
         [Test]
         public void ReadGroup_UnknownFields_WrongEndGroupTag()
         {
-            MemoryStream ms = new MemoryStream();
-            CodedOutputStream output = new CodedOutputStream(ms);
+            var ms = new MemoryStream();
+            var output = new CodedOutputStream(ms);
             output.WriteTag(WireFormat.MakeTag(14, WireFormat.WireType.StartGroup));
             // end group with different field number
             output.WriteTag(WireFormat.MakeTag(15, WireFormat.WireType.EndGroup));
@@ -654,7 +654,7 @@ public void ReadNegativeSizedBytesThrowsInvalidProtocolBufferException()
             output.Flush();
             ms.Position = 0;
 
-            CodedInputStream input = new CodedInputStream(ms);
+            var input = new CodedInputStream(ms);
 
             Assert.AreEqual(tag, input.ReadTag());
             Assert.Throws<InvalidProtocolBufferException>(() => input.ReadBytes());
@@ -694,26 +694,24 @@ public void TestNegativeEnum()
         [Test]
         public void TestSlowPathAvoidance()
         {
-            using (var ms = new MemoryStream())
-            {
-                CodedOutputStream output = new CodedOutputStream(ms);
-                output.WriteTag(1, WireFormat.WireType.LengthDelimited);
-                output.WriteBytes(ByteString.CopyFrom(new byte[100]));
-                output.WriteTag(2, WireFormat.WireType.LengthDelimited);
-                output.WriteBytes(ByteString.CopyFrom(new byte[100]));
-                output.Flush();
+            using var ms = new MemoryStream();
+            var output = new CodedOutputStream(ms);
+            output.WriteTag(1, WireFormat.WireType.LengthDelimited);
+            output.WriteBytes(ByteString.CopyFrom(new byte[100]));
+            output.WriteTag(2, WireFormat.WireType.LengthDelimited);
+            output.WriteBytes(ByteString.CopyFrom(new byte[100]));
+            output.Flush();
 
-                ms.Position = 0;
-                CodedInputStream input = new CodedInputStream(ms, new byte[ms.Length / 2], 0, 0, false);
+            ms.Position = 0;
+            CodedInputStream input = new CodedInputStream(ms, new byte[ms.Length / 2], 0, 0, false);
 
-                uint tag = input.ReadTag();
-                Assert.AreEqual(1, WireFormat.GetTagFieldNumber(tag));
-                Assert.AreEqual(100, input.ReadBytes().Length);
+            uint tag = input.ReadTag();
+            Assert.AreEqual(1, WireFormat.GetTagFieldNumber(tag));
+            Assert.AreEqual(100, input.ReadBytes().Length);
 
-                tag = input.ReadTag();
-                Assert.AreEqual(2, WireFormat.GetTagFieldNumber(tag));
-                Assert.AreEqual(100, input.ReadBytes().Length);
-            }
+            tag = input.ReadTag();
+            Assert.AreEqual(2, WireFormat.GetTagFieldNumber(tag));
+            Assert.AreEqual(100, input.ReadBytes().Length);
         }
 
         [Test]
@@ -927,31 +925,27 @@ public void TestParseMessagesCloseTo2G()
         {
             byte[] serializedMessage = GenerateBigSerializedMessage();
             // How many of these big messages do we need to take us near our 2GB limit?
-            int count = Int32.MaxValue / serializedMessage.Length;
+            int count = int.MaxValue / serializedMessage.Length;
             // Now make a MemoryStream that will fake a near-2GB stream of messages by returning
             // our big serialized message 'count' times.
-            using (RepeatingMemoryStream stream = new RepeatingMemoryStream(serializedMessage, count))
-            {
-                Assert.DoesNotThrow(()=>TestAllTypes.Parser.ParseFrom(stream));
-            }
+            using var stream = new RepeatingMemoryStream(serializedMessage, count);
+            Assert.DoesNotThrow(() => TestAllTypes.Parser.ParseFrom(stream));
         }
 
         [Test]
         public void TestParseMessagesOver2G()
         {
             byte[] serializedMessage = GenerateBigSerializedMessage();
             // How many of these big messages do we need to take us near our 2GB limit?
-            int count = Int32.MaxValue / serializedMessage.Length;
+            int count = int.MaxValue / serializedMessage.Length;
             // Now add one to take us over the 2GB limit
             count++;
             // Now make a MemoryStream that will fake a near-2GB stream of messages by returning
             // our big serialized message 'count' times.
-            using (RepeatingMemoryStream stream = new RepeatingMemoryStream(serializedMessage, count))
-            {
-                Assert.Throws<InvalidProtocolBufferException>(() => TestAllTypes.Parser.ParseFrom(stream),
-                    "Protocol message was too large.  May be malicious.  " +
-                    "Use CodedInputStream.SetSizeLimit() to increase the size limit.");
-            }
+            using var stream = new RepeatingMemoryStream(serializedMessage, count);
+            Assert.Throws<InvalidProtocolBufferException>(() => TestAllTypes.Parser.ParseFrom(stream),
+                "Protocol message was too large.  May be malicious.  " +
+                "Use CodedInputStream.SetSizeLimit() to increase the size limit.");
         }
 
         /// <returns>A serialized big message</returns>