STJ source generation in a WPF project broken

[bachratyg]

Description

Referencing certain NuGets in a Wpf project and using STJ source generation the build breaks.

Reproduction Steps

1. create new WPF project
2. add reference to Microsoft.Extensions.Hosting or anything that indirectly depends on System.Text.Json
3. add the following source:

   
   using System.Text.Json.Serialization;

[JsonSerializable(typeof(string[]))] public partial class JsonInfo : JsonSerializerContext { }

4. build with `dotnet build`, VS, whatever

Minimal repro code: https://gist.github.com/bachratyg/09df487726946b05728d5129044ca574

### Expected behavior

Should build just fine

### Actual behavior

Output from dotnet build

MSBuild version 17.5.0+6f08c67f3 for .NET Determining projects to restore... Restored \WpfApp1.csproj (in 352 ms).

\System.Text.Json.SourceGeneration\System.Text.Json.SourceGeneration.JsonSourceGenerator\JsonInfo.g.cs(9,6): error CS0579: Duplicate 'global::System.CodeDom.Compiler.GeneratedCodeAttribute' attribute [\WpfApp1_oet233uf_wpftmp.csproj] \JsonStuff.cs(4,22): error CS8646: 'IJsonTypeInfoResolver.GetTypeInfo(Type, JsonSerializerOptions)' is explicitly implemented more than once. [\WpfApp1_oet233uf_wpftmp.csproj] \System.Text.Json.SourceGeneration\System.Text.Json.SourceGeneration.JsonSourceGenerator\JsonInfo.String.g.cs(10,102): error CS0102: The type 'JsonInfo' already contains a definition for '_String' [\WpfApp1_oet233uf_wpftmp.csproj] \System.Text.Json.SourceGeneration\System.Text.Json.SourceGeneration.JsonSourceGenerator\JsonInfo.String.g.cs(14,100): error CS0102: The type 'JsonInfo' already contains a definition for 'String' [\WpfApp1_oet233uf_wpftmp.csproj] \System.Text.Json.SourceGeneration\System.Text.Json.SourceGeneration.JsonSourceGenerator\JsonInfo.String.g.cs(19,101): error CS0111: Type 'JsonInfo' already defines a member called 'Create_String' with the same parameter types [\WpfApp1_oet233uf_wpftmp.csproj] \System.Text.Json.SourceGeneration\System.Text.Json.SourceGeneration.JsonSourceGenerator\JsonInfo.StringArray.g.cs(10,104): error CS0102: The type 'JsonInfo' already contains a definition for '_StringArray' [\WpfApp1_oet233uf_wpftmp.csproj] \System.Text.Json.SourceGeneration\System.Text.Json.SourceGeneration.JsonSourceGenerator\JsonInfo.StringArray.g.cs(14,102): error CS0102: The type 'JsonInfo' already contains a definition for 'StringArray' [\WpfApp1_oet233uf_wpftmp.csproj] \System.Text.Json.SourceGeneration\System.Text.Json.SourceGeneration.JsonSourceGenerator\JsonInfo.StringArray.g.cs(19,103): error CS0111: Type 'JsonInfo' already defines a member called 'Create_StringArray' with the same parameter types [\WpfApp1_oet233uf_wpftmp.csproj] \System.Text.Json.SourceGeneration\System.Text.Json.SourceGeneration.JsonSourceGenerator\JsonInfo.StringArray.g.cs(51,22): error CS0111: Type 'JsonInfo' already defines a member called 'StringArraySerializeHandler' with the same parameter types [\WpfApp1_oet233uf_wpftmp.csproj] \System.Text.Json.SourceGeneration\System.Text.Json.SourceGeneration.JsonSourceGenerator\JsonInfo.g.cs(13,71): error CS0102: The type 'JsonInfo' already contains a definition for 's_defaultOptions' [\WpfApp1_oet233uf_wpftmp.csproj] \System.Text.Json.SourceGeneration\System.Text.Json.SourceGeneration.JsonSourceGenerator\JsonInfo.g.cs(22,42): error CS0102: The type 'JsonInfo' already contains a definition for 's_defaultContext' [\WpfApp1_oet233uf_wpftmp.csproj] \System.Text.Json.SourceGeneration\System.Text.Json.SourceGeneration.JsonSourceGenerator\JsonInfo.g.cs(27,40): error CS0102: The type 'JsonInfo' already contains a definition for 'Default' [\WpfApp1_oet233uf_wpftmp.csproj] \System.Text.Json.SourceGeneration\System.Text.Json.SourceGeneration.JsonSourceGenerator\JsonInfo.g.cs(32,76): error CS0102: The type 'JsonInfo' already contains a definition for 'GeneratedSerializerOptions' [\WpfApp1_oet233uf_wpftmp.csproj] \System.Text.Json.SourceGeneration\System.Text.Json.SourceGeneration.JsonSourceGenerator\JsonInfo.g.cs(35,16): error CS0111: Type 'JsonInfo' already defines a member called 'JsonInfo' with the same parameter types [\WpfApp1_oet233uf_wpftmp.csproj] \System.Text.Json.SourceGeneration\System.Text.Json.SourceGeneration.JsonSourceGenerator\JsonInfo.g.cs(40,16): error CS0111: Type 'JsonInfo' already defines a member called 'JsonInfo' with the same parameter types [\WpfApp1_oet233uf_wpftmp.csproj] \System.Text.Json.SourceGeneration\System.Text.Json.SourceGeneration.JsonSourceGenerator\JsonInfo.g.cs(44,78): error CS0111: Type 'JsonInfo' already defines a member called 'GetRuntimeProvidedCustomConverter' with the same parameter types [\WpfApp1_oet233uf_wpftmp.csproj] \System.Text.Json.SourceGeneration\System.Text.Json.SourceGeneration.JsonSourceGenerator\JsonInfo.GetJsonTypeInfo.g.cs(11,86): error CS0111: Type 'JsonInfo' already defines a member called 'GetTypeInfo' with the same parameter types [\WpfApp1_oet233uf_wpftmp.csproj] \System.Text.Json.SourceGeneration\System.Text.Json.SourceGeneration.JsonSourceGenerator\JsonInfo.GetJsonTypeInfo.g.cs(26,141): error CS0111: Type 'JsonInfo' already defines a member called 'global::System.Text.Json.Serialization.Metadata.IJsonTypeInfoResolver.GetTypeInfo' with the same parameter types [\WpfApp1_oet233uf_wpftmp.csproj] Build FAILED. \System.Text.Json.SourceGeneration\System.Text.Json.SourceGeneration.JsonSourceGenerator\JsonInfo.g.cs(9,6): error CS0579: Duplicate 'global::System.CodeDom.Compiler.GeneratedCodeAttribute' attribute [\WpfApp1_oet233uf_wpftmp.csproj] \JsonStuff.cs(4,22): error CS8646: 'IJsonTypeInfoResolver.GetTypeInfo(Type, JsonSerializerOptions)' is explicitly implemented more than once. [\WpfApp1_oet233uf_wpftmp.csproj] \System.Text.Json.SourceGeneration\System.Text.Json.SourceGeneration.JsonSourceGenerator\JsonInfo.String.g.cs(10,102): error CS0102: The type 'JsonInfo' already contains a definition for '_String' [\WpfApp1_oet233uf_wpftmp.csproj] \System.Text.Json.SourceGeneration\System.Text.Json.SourceGeneration.JsonSourceGenerator\JsonInfo.String.g.cs(14,100): error CS0102: The type 'JsonInfo' already contains a definition for 'String' [\WpfApp1_oet233uf_wpftmp.csproj] \System.Text.Json.SourceGeneration\System.Text.Json.SourceGeneration.JsonSourceGenerator\JsonInfo.String.g.cs(19,101): error CS0111: Type 'JsonInfo' already defines a member called 'Create_String' with the same parameter types [\WpfApp1_oet233uf_wpftmp.csproj] \System.Text.Json.SourceGeneration\System.Text.Json.SourceGeneration.JsonSourceGenerator\JsonInfo.StringArray.g.cs(10,104): error CS0102: The type 'JsonInfo' already contains a definition for '_StringArray' [\WpfApp1_oet233uf_wpftmp.csproj] \System.Text.Json.SourceGeneration\System.Text.Json.SourceGeneration.JsonSourceGenerator\JsonInfo.StringArray.g.cs(14,102): error CS0102: The type 'JsonInfo' already contains a definition for 'StringArray' [\WpfApp1_oet233uf_wpftmp.csproj] \System.Text.Json.SourceGeneration\System.Text.Json.SourceGeneration.JsonSourceGenerator\JsonInfo.StringArray.g.cs(19,103): error CS0111: Type 'JsonInfo' already defines a member called 'Create_StringArray' with the same parameter types [\WpfApp1_oet233uf_wpftmp.csproj] \System.Text.Json.SourceGeneration\System.Text.Json.SourceGeneration.JsonSourceGenerator\JsonInfo.StringArray.g.cs(51,22): error CS0111: Type 'JsonInfo' already defines a member called 'StringArraySerializeHandler' with the same parameter types [\WpfApp1_oet233uf_wpftmp.csproj] \System.Text.Json.SourceGeneration\System.Text.Json.SourceGeneration.JsonSourceGenerator\JsonInfo.g.cs(13,71): error CS0102: The type 'JsonInfo' already contains a definition for 's_defaultOptions' [\WpfApp1_oet233uf_wpftmp.csproj] \System.Text.Json.SourceGeneration\System.Text.Json.SourceGeneration.JsonSourceGenerator\JsonInfo.g.cs(22,42): error CS0102: The type 'JsonInfo' already contains a definition for 's_defaultContext' [\WpfApp1_oet233uf_wpftmp.csproj] \System.Text.Json.SourceGeneration\System.Text.Json.SourceGeneration.JsonSourceGenerator\JsonInfo.g.cs(27,40): error CS0102: The type 'JsonInfo' already contains a definition for 'Default' [\WpfApp1_oet233uf_wpftmp.csproj] \System.Text.Json.SourceGeneration\System.Text.Json.SourceGeneration.JsonSourceGenerator\JsonInfo.g.cs(32,76): error CS0102: The type 'JsonInfo' already contains a definition for 'GeneratedSerializerOptions' [\WpfApp1_oet233uf_wpftmp.csproj] \System.Text.Json.SourceGeneration\System.Text.Json.SourceGeneration.JsonSourceGenerator\JsonInfo.g.cs(35,16): error CS0111: Type 'JsonInfo' already defines a member called 'JsonInfo' with the same parameter types [\WpfApp1_oet233uf_wpftmp.csproj] \System.Text.Json.SourceGeneration\System.Text.Json.SourceGeneration.JsonSourceGenerator\JsonInfo.g.cs(40,16): error CS0111: Type 'JsonInfo' already defines a member called 'JsonInfo' with the same parameter types [\WpfApp1_oet233uf_wpftmp.csproj] \System.Text.Json.SourceGeneration\System.Text.Json.SourceGeneration.JsonSourceGenerator\JsonInfo.g.cs(44,78): error CS0111: Type 'JsonInfo' already defines a member called 'GetRuntimeProvidedCustomConverter' with the same parameter types [\WpfApp1_oet233uf_wpftmp.csproj] \System.Text.Json.SourceGeneration\System.Text.Json.SourceGeneration.JsonSourceGenerator\JsonInfo.GetJsonTypeInfo.g.cs(11,86): error CS0111: Type 'JsonInfo' already defines a member called 'GetTypeInfo' with the same parameter types [\WpfApp1_oet233uf_wpftmp.csproj] \System.Text.Json.SourceGeneration\System.Text.Json.SourceGeneration.JsonSourceGenerator\JsonInfo.GetJsonTypeInfo.g.cs(26,141): error CS0111: Type 'JsonInfo' already defines a member called 'global::System.Text.Json.Serialization.Metadata.IJsonTypeInfoResolver.GetTypeInfo' with the same parameter types [\WpfApp1_oet233uf_wpftmp.csproj] 0 Warning(s) 18 Error(s) ``` ### Regression? Might be related to #6792 (pull #6793, #6799) ### Known Workarounds None that I found. Tried https://github.com/dotnet/wpf/pull/6680#issuecomment-1183552170 as suggested in #6792, didn't work ### Impact Can't use STJ source generator together with libraries that also depend on STJ. E.g. `BackgroundService` from `Microsoft.Extensions.Hosting` or stuff from `Microsoft.Extensions.Configuration.Json` ### Configuration Does not seem to be specific to configuration

dotnet --info

``` .NET SDK: Version: 7.0.202 Commit: 6c74320bc3 Runtime Environment: OS Name: Windows OS Version: 10.0.19045 OS Platform: Windows RID: win10-x64 Base Path: C:\Program Files\dotnet\sdk\7.0.202\ Host: Version: 7.0.4 Architecture: x64 Commit: 0a396acafe .NET SDKs installed: 7.0.202 [C:\Program Files\dotnet\sdk] .NET runtimes installed: Microsoft.AspNetCore.App 6.0.15 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App] Microsoft.AspNetCore.App 7.0.4 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App] Microsoft.NETCore.App 6.0.15 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App] Microsoft.NETCore.App 7.0.4 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App] Microsoft.WindowsDesktop.App 6.0.15 [C:\Program Files\dotnet\shared\Microsoft.WindowsDesktop.App] Microsoft.WindowsDesktop.App 7.0.4 [C:\Program Files\dotnet\shared\Microsoft.WindowsDesktop.App] Other architectures found: arm64 [C:\Program Files\dotnet] registered at [HKLM\SOFTWARE\dotnet\Setup\InstalledVersions\arm64\InstallLocation] x86 [C:\Program Files (x86)\dotnet] registered at [HKLM\SOFTWARE\dotnet\Setup\InstalledVersions\x86\InstallLocation] Environment variables: Not set global.json file: Not found Learn more: https://aka.ms/dotnet/info Download .NET: https://aka.ms/dotnet/download ```

### Other information _No response_

[kevincathcart-cas]

Analysis of cause

At its core, this stems from having two different versions of the source generator (a type of analyzer) run during a build.

This error happens in CoreCompile as depended upon by _CompileTemporaryAssembly, which is executed in a new subbuild by GenerateTemporaryTargetAssembly.

This task does not use ResolveAssemblies (which avoids duplicates via _HandlePackageFileConflicts). Instead it does a more limited resolution of package assemblies.

What is specifically happening here is that GenerateTemporaryTargetAssembly is passed the complete list of analyzers that the main compilation used. It pre-adds those as <Analyzer> items. It then resolves packages, which potentially adds some analyzers again. Finally, it attempts to deduplicate these with a RemoveDuplicateAnalyzers target, which was added in PR #6799.

That works fine for deduplicating a source generator that only lives in a nuget package, but does not work for deduping a source generator between an in-box version and one from a nuget package.

Temporary workaround

As a temporary workaround, users can add thr following to their csproj (adjust to be correct culture for main XAML files):

<UICulture>en-US</UICulture>

and also add this attribute (with the same value as UICulture property):

[assembly: NeutralResourcesLanguage("en-US", UltimateResourceFallbackLocation.Satellite)]

This avoids the using GenerateTemporaryTargetAssembly at the cost of creating a satellite assembly to house the default version of the compiled markup, instead of embedding it into the main assembly.

Proposed solution

Have GenerateTemporaryTargetAssembly add the analyzers it is passed as new <PreresolvedAnalyzer> item type, either instead or in addition to passing them as <Analyzer> items.

Then instead of RemoveDuplicateAnalyzers, we can do:

<Target Name="UsePreresolvedAnalyzers" Condition="'@(PreresolvedAnalyzer)' != ''" BeforeTargets="CoreCompile">
    <ItemGroup>
        <Analyzer Remove="@(Analyzer)" />
        <Analyzer Include="@(PreresolvedAnalyzer)" />
    </ItemGroup>
  </Target>

The result of this is that we end up using the exact same set of source generators as regular build, which seems to be the intention, given that the code was already adding them as <Analyzer> items in the first place.

[HanJaeJoon]

I have same issue in .NET SDK 8.0.301. Only temporary workaround works for me. Thanks anyway.