Fixed some review comments

src/Avalonia.Base/Avalonia.Base.csproj

@@ -7,7 +7,9 @@
     <IsPackable>false</IsPackable>
   </PropertyGroup>
   <ItemGroup>
-    <ProjectReference Include="..\Avalonia.Build.Tasks\Avalonia.Build.Tasks.csproj"/>
+    <ProjectReference Include="..\Avalonia.Build.Tasks\Avalonia.Build.Tasks.csproj">
+      <ReferenceOutputAssembly>false</ReferenceOutputAssembly>
+    </ProjectReference>
   </ItemGroup>
   <Import Project="..\..\build\Base.props" />
   <Import Project="..\..\build\Binding.props" />

src/Avalonia.Base/Utilities/AvaloniaResourcesIndex.cs

@@ -9,10 +9,7 @@ using System.Runtime.Serialization.Json;
 
 namespace Avalonia.Utilities
 {
-    #if !BUILDTASK
-    public 
-    #endif
-        static class AvaloniaResourcesIndexReaderWriter
+    public static class AvaloniaResourcesIndexReaderWriter
     {
         private const int LastKnownVersion = 1;
         public static List<AvaloniaResourcesIndexEntry> Read(Stream stream)

src/Avalonia.Build.Tasks/Avalonia.Build.Tasks.csproj

@@ -4,6 +4,7 @@
         <TargetFramework>netstandard2.0</TargetFramework>
         <BuildOutputTargetFolder>tools</BuildOutputTargetFolder>
         <DefineConstants>$(DefineConstants);BUILDTASK</DefineConstants>
+        <Packable>false</Packable>
     </PropertyGroup>
 
     <ItemGroup>
@@ -15,6 +16,4 @@
       </Compile>
       <PackageReference Include="Microsoft.Build.Framework" Version="15.1.548" />
     </ItemGroup>
-  <!-- Disable built-in Pack target -->
-  <Target Name="Pack"/>
 </Project>

src/Avalonia.Build.Tasks/BuildEngineErrorCode.cs

@@ -0,0 +1,9 @@
+namespace Avalonia.Build.Tasks
+{
+    public enum BuildEngineErrorCode
+    {
+        InvalidXAML = 1,
+        DuplicateXClass = 2,
+        LegacyResmScheme = 3,
+    }
+}

src/Avalonia.Build.Tasks/Extensions.cs

@@ -4,16 +4,18 @@ namespace Avalonia.Build.Tasks
 {
     public static class Extensions
     {
-        public static void LogError(this IBuildEngine engine, string file, string message)
+        static string FormatErrorCode(BuildEngineErrorCode code) => $"AVLN:{(int)code:0000}";
+
+        public static void LogError(this IBuildEngine engine, BuildEngineErrorCode code, string file, string message)
         {
-            engine.LogErrorEvent(new BuildErrorEventArgs("Avalonia", "0000", file ?? "", 0, 0, 0, 0, message, "",
-                "Avalonia"));
+            engine.LogErrorEvent(new BuildErrorEventArgs("Avalonia", FormatErrorCode(code), file ?? "", 0, 0, 0, 0, message, 
+                "", "Avalonia"));
         }
         
-        public static void LogWarning(this IBuildEngine engine, string file, string message)
+        public static void LogWarning(this IBuildEngine engine, BuildEngineErrorCode code, string file, string message)
         {
-            engine.LogWarningEvent(new BuildWarningEventArgs("Avalonia", "0000", file ?? "", 0, 0, 0, 0, message, "",
-                "Avalonia"));
+            engine.LogWarningEvent(new BuildWarningEventArgs("Avalonia", FormatErrorCode(code), file ?? "", 0, 0, 0, 0, message,
+                "", "Avalonia"));
         }
     }
 }

src/Avalonia.Build.Tasks/GenerateAvaloniaResourcesTask.cs

@@ -67,7 +67,7 @@ namespace Avalonia.Build.Tasks
 
         List<Source> BuildResourceSources() => Resources.Select(r => new Source(r.ItemSpec, Root)).ToList();
 
-        void Pack(Stream output, List<Source> sources)
+        private void Pack(Stream output, List<Source> sources)
         {
             var offsets = new Dictionary<Source, int>();
             var coffset = 0;
@@ -94,7 +94,7 @@ namespace Avalonia.Build.Tasks
             }
         }
 
-        bool PreProcessXamlFiles(List<Source> sources)
+        private bool PreProcessXamlFiles(List<Source> sources)
         {
             var typeToXamlIndex = new Dictionary<string, string>(); 
             
@@ -109,7 +109,7 @@ namespace Avalonia.Build.Tasks
                     }
                     catch(Exception e)
                     {
-                        BuildEngine.LogError(s.SystemPath, "File doesn't contain valid XAML: " + e);
+                        BuildEngine.LogError(BuildEngineErrorCode.InvalidXAML, s.SystemPath, "File doesn't contain valid XAML: " + e);
                         return false;
                     }
 
@@ -118,7 +118,7 @@ namespace Avalonia.Build.Tasks
                         if (typeToXamlIndex.ContainsKey(info.XClass))
                         {
                             
-                            BuildEngine.LogError(s.SystemPath,
+                            BuildEngine.LogError(BuildEngineErrorCode.DuplicateXClass, s.SystemPath,
                                 $"Duplicate x:Class directive, {info.XClass} is already used in {typeToXamlIndex[info.XClass]}");
                             return false;
                         }
@@ -140,7 +140,8 @@ namespace Avalonia.Build.Tasks
         public bool Execute()
         {
             foreach(var r in EmbeddedResources.Where(r=>r.ItemSpec.EndsWith(".xaml")||r.ItemSpec.EndsWith(".paml")))
-                BuildEngine.LogWarning(r.ItemSpec, "XAML file is packed using legacy EmbeddedResource/resm scheme, relative URIs won't work");
+                BuildEngine.LogWarning(BuildEngineErrorCode.LegacyResmScheme, r.ItemSpec,
+                    "XAML file is packed using legacy EmbeddedResource/resm scheme, relative URIs won't work");
             var resources = BuildResourceSources();
 
             if (!PreProcessXamlFiles(resources))

src/Shared/PlatformSupport/AssetLoader.cs

@@ -296,60 +296,60 @@ namespace Avalonia.Shared.PlatformSupport
         }
         
         class SlicedStream : Stream
-            {
-                private readonly Stream _baseStream;
-                private readonly int _from;
-
-                public SlicedStream(Stream baseStream, int from, int length)
-                {
-                    Length = length;
-                    _baseStream = baseStream;
-                    _from = from;
-                    _baseStream.Position = from;
-                }
-                public override void Flush()
-                {
-                }
+        {
+            private readonly Stream _baseStream;
+            private readonly int _from;
 
-                public override int Read(byte[] buffer, int offset, int count)
-                {
-                    return _baseStream.Read(buffer, offset, (int)Math.Min(count, Length - Position));
-                }
+            public SlicedStream(Stream baseStream, int from, int length)
+            {
+                Length = length;
+                _baseStream = baseStream;
+                _from = from;
+                _baseStream.Position = from;
+            }
+            public override void Flush()
+            {
+            }
 
-                public override long Seek(long offset, SeekOrigin origin)
-                {
-                    if (origin == SeekOrigin.Begin)
-                        Position = offset;
-                    if (origin == SeekOrigin.End)
-                        Position = _from + Length + offset;
-                    if (origin == SeekOrigin.Current)
-                        Position = Position + offset;
-                    return Position;
-                }
+            public override int Read(byte[] buffer, int offset, int count)
+            {
+                return _baseStream.Read(buffer, offset, (int)Math.Min(count, Length - Position));
+            }
 
-                public override void SetLength(long value) => throw new NotSupportedException();
+            public override long Seek(long offset, SeekOrigin origin)
+            {
+                if (origin == SeekOrigin.Begin)
+                    Position = offset;
+                if (origin == SeekOrigin.End)
+                    Position = _from + Length + offset;
+                if (origin == SeekOrigin.Current)
+                    Position = Position + offset;
+                return Position;
+            }
 
-                public override void Write(byte[] buffer, int offset, int count) => throw new NotSupportedException();
+            public override void SetLength(long value) => throw new NotSupportedException();
 
-                public override bool CanRead => true;
-                public override bool CanSeek => _baseStream.CanRead;
-                public override bool CanWrite => false;
-                public override long Length { get; }
-                public override long Position
-                {
-                    get => _baseStream.Position - _from;
-                    set => _baseStream.Position = value + _from;
-                }
+            public override void Write(byte[] buffer, int offset, int count) => throw new NotSupportedException();
 
-                protected override void Dispose(bool disposing)
-                {
-                    if (disposing)
-                        _baseStream.Dispose();
-                }
+            public override bool CanRead => true;
+            public override bool CanSeek => _baseStream.CanRead;
+            public override bool CanWrite => false;
+            public override long Length { get; }
+            public override long Position
+            {
+                get => _baseStream.Position - _from;
+                set => _baseStream.Position = value + _from;
+            }
 
-                public override void Close() => _baseStream.Close();
+            protected override void Dispose(bool disposing)
+            {
+                if (disposing)
+                    _baseStream.Dispose();
             }
 
+            public override void Close() => _baseStream.Close();
+        }
+
         private class AssemblyDescriptor
         {
             public AssemblyDescriptor(Assembly assembly)