Fix CsWin32 api doc reading in newer C# compiler versions

.editorconfig

@@ -188,5 +188,9 @@ dotnet_diagnostic.DOC202.severity = warning
 # CA1062: Validate arguments of public methods
 dotnet_diagnostic.CA1062.severity = suggestion
 
+# MessagePack analyzer diagnostics
+dotnet_diagnostic.MsgPack001.severity = error
+dotnet_diagnostic.MsgPack002.severity = error
+
 [*.sln]
 indent_style = tab

Directory.Packages.props

@@ -3,18 +3,17 @@
   <PropertyGroup>
     <ManagePackageVersionsCentrally>true</ManagePackageVersionsCentrally>
     <CentralPackageTransitivePinningEnabled>true</CentralPackageTransitivePinningEnabled>
-
     <MetadataVersion>54.0.44-preview</MetadataVersion>
     <WDKMetadataVersion>0.7.3-experimental</WDKMetadataVersion>
     <!-- <DiaMetadataVersion>0.2.185-preview-g7e1e6a442c</DiaMetadataVersion> -->
     <ApiDocsVersion>0.1.42-alpha</ApiDocsVersion>
-
     <CodeAnalysisVersion>4.6.0</CodeAnalysisVersion>
     <CodeAnalysisVersion Condition="'$(IsTestProject)'!='true'">3.11.0</CodeAnalysisVersion>
   </PropertyGroup>
   <ItemGroup>
     <PackageVersion Include="IsExternalInit" Version="1.0.3" />
     <PackageVersion Include="MessagePack" Version="2.2.85" />
+    <PackageVersion Include="MessagePackAnalyzer" Version="2.5.108" />
     <PackageVersion Include="Microsoft.CodeAnalysis.BannedApiAnalyzers" Version="3.3.4" />
     <PackageVersion Include="Microsoft.CodeAnalysis.Common" Version="$(CodeAnalysisVersion)" />
     <PackageVersion Include="Microsoft.CodeAnalysis.CSharp.SourceGenerators.Testing.XUnit" Version="1.1.2-beta1.23323.1" />
@@ -54,4 +53,4 @@
   <ItemGroup>
     <GlobalPackageReference Include="Microsoft.SourceLink.GitHub" Version="1.1.1" />
   </ItemGroup>
-</Project>
+</Project>

src/Microsoft.Windows.CsWin32/Docs.cs

@@ -2,6 +2,8 @@
 // Licensed under the MIT license. See LICENSE file in the project root for full license information.
 
 using MessagePack;
+using MessagePack.Formatters;
+using MessagePack.Resolvers;
 
 namespace Microsoft.Windows.CsWin32;
 
@@ -11,6 +13,10 @@ namespace Microsoft.Windows.CsWin32;
 public class Docs
 {
     private static readonly Dictionary<string, Docs> DocsByPath = new Dictionary<string, Docs>(StringComparer.OrdinalIgnoreCase);
+    private static readonly MessagePackSerializerOptions MsgPackOptions = MessagePackSerializerOptions.Standard.WithResolver(
+        CompositeResolver.Create(
+            new IMessagePackFormatter[] { new ApiDetailsFormatter() },
+            new IFormatterResolver[] { StandardResolver.Instance }));
 
     private readonly Dictionary<string, ApiDetails> apisAndDocs;
 
@@ -35,7 +41,7 @@ public static Docs Get(string docsPath)
         }
 
         using FileStream docsStream = File.OpenRead(docsPath);
-        Dictionary<string, ApiDetails>? data = MessagePackSerializer.Deserialize<Dictionary<string, ApiDetails>>(docsStream);
+        Dictionary<string, ApiDetails>? data = MessagePackSerializer.Deserialize<Dictionary<string, ApiDetails>>(docsStream, MsgPackOptions);
         var docs = new Docs(data);
 
         lock (DocsByPath)
@@ -85,4 +91,67 @@ public static Docs Merge(IReadOnlyList<Docs> docs)
     }
 
     internal bool TryGetApiDocs(string apiName, [NotNullWhen(true)] out ApiDetails? docs) => this.apisAndDocs.TryGetValue(apiName, out docs);
+
+    /// <summary>
+    /// Formatter for <see cref="ApiDetails"/>.
+    /// </summary>
+    /// <remarks>
+    /// We have to manually write this to avoid using the <see cref="DynamicObjectResolver"/> since newer C# compiler versions fail
+    /// when that dynamic type creator creates a non-collectible assembly that our own evidently collectible assembly references.
+    /// </remarks>
+    private class ApiDetailsFormatter : IMessagePackFormatter<ApiDetails>
+    {
+        public ApiDetails Deserialize(ref MessagePackReader reader, MessagePackSerializerOptions options)
+        {
+            string? helpLink = null;
+            string? description = null;
+            string? remarks = null;
+            Dictionary<string, string>? parameters = null;
+            Dictionary<string, string>? fields = null;
+            string? returnValue = null;
+            int count = reader.ReadArrayHeader();
+            for (int i = 0; i < count; i++)
+            {
+                switch (i)
+                {
+                    case 0:
+                        helpLink = reader.ReadString();
+                        break;
+                    case 1:
+                        description = reader.ReadString();
+                        break;
+                    case 2:
+                        remarks = reader.ReadString();
+                        break;
+                    case 3:
+                        parameters = options.Resolver.GetFormatterWithVerify<Dictionary<string, string>>().Deserialize(ref reader, options);
+                        break;
+                    case 4:
+                        fields = options.Resolver.GetFormatterWithVerify<Dictionary<string, string>>().Deserialize(ref reader, options);
+                        break;
+                    case 5:
+                        returnValue = reader.ReadString();
+                        break;
+                    default:
+                        reader.Skip();
+                        break;
+                }
+            }
+
+            return new ApiDetails
+            {
+                HelpLink = helpLink is null ? null : new Uri(helpLink),
+                Description = description,
+                Remarks = remarks,
+                Parameters = parameters ?? new Dictionary<string, string>(),
+                Fields = fields ?? new Dictionary<string, string>(),
+                ReturnValue = returnValue,
+            };
+        }
+
+        public void Serialize(ref MessagePackWriter writer, ApiDetails value, MessagePackSerializerOptions options)
+        {
+            throw new NotImplementedException();
+        }
+    }
 }

src/Microsoft.Windows.CsWin32/Microsoft.Windows.CsWin32.csproj

@@ -44,6 +44,7 @@
   <ItemGroup>
     <PackageReference Include="IsExternalInit" PrivateAssets="all" />
     <PackageReference Include="MessagePack" />
+    <PackageReference Include="MessagePackAnalyzer" PrivateAssets="all" />
     <PackageReference Include="Microsoft.CodeAnalysis.BannedApiAnalyzers" PrivateAssets="all" />
     <PackageReference Include="Microsoft.CodeAnalysis.CSharp" />
     <PackageReference Include="Microsoft.Windows.SDK.Win32Metadata" GeneratePathProperty="true" PrivateAssets="none" />

src/Microsoft.Windows.CsWin32/SourceGenerator.cs

@@ -363,7 +363,7 @@ private static IReadOnlyList<string> CollectMetadataPaths(GeneratorExecutionCont
                     }
                     catch (Exception e)
                     {
-                        context.ReportDiagnostic(Diagnostic.Create(DocParsingError, null, path, e.Message));
+                        context.ReportDiagnostic(Diagnostic.Create(DocParsingError, null, path, e));
                     }
                 }