Emit attributes into the consuming compilation

[NoahStolk]

Fixes #1.

The problem

EnumGenerator.Package set DevelopmentDependency=true while also shipping EnumGenerator.Attributes.dll in lib/netstandard2.0. NuGet writes this on install for a development dependency:

<IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>

Note the absent compile. The attributes assembly was therefore invisible to consumers, who had to hand-add compile after every install. The package was claiming "nothing to reference" while shipping something to reference.

The fix

Rather than push consumers toward including the compile asset (which is what the issue title suggests), this removes the need for it entirely — the package becomes a genuine development dependency.

AttributeSourceUtils now holds the attribute source, which EnumIncrementalGenerator emits via RegisterPostInitializationOutput. Post-initialization is mandatory here: both providers resolve [GenerateEnumUtilities] through the semantic model, and only post-initialization sources are visible to it during the generator run. Moving this to RegisterSourceOutput would silently break all detection.

The EnumGenerator.Attributes project is deleted. The package now contains nothing but the generator:

analyzers/dotnet/cs/EnumGenerator.dll
README.md

No lib/ folder, no assembly to reference, no runtime dependency, and the default PackageReference needs no editing.

Two packaging bugs found while verifying are fixed alongside:

• lib/netstandard2.0/EnumGenerator.Package.dll — the packaging project's own empty assembly was leaking into the package (IncludeBuildOutput=false).
• The empty netstandard2.0 dependency group tripped NU5128 once lib/ was gone (SuppressDependenciesWhenPacking=true).

Verification

EnumGenerator.Tests.NuGetIntegration now declares the exact metadata dotnet add package writes, instead of the hand-patched version with compile bolted on. It is the regression test for this issue — if it stops compiling, the package layout is wrong, not the test.

• Snapshot tests: 28/28. The 27 pre-existing snapshots are unchanged, confirming generated output is unaffected; the new one covers the emitted attributes.
• In-solution integration tests: 13/13.
• NuGet integration tests (packed nuget, default IncludeAssets): 13/13.
• EnumGenerator.Sample runs correctly.

Breaking change

The attributes go from public in a referenced assembly to internal in each compilation. This only matters for code that reflects over GenerateEnumUtilitiesAttribute at runtime or re-exposes it across assembly boundaries — unlikely, since the attribute only drives generation. Version bumped to 0.6.0 accordingly.

No new constraint on consumers: the generic GenerateEnumUtilitiesAttribute<T> needs C# 11, which the README already requires for UTF-8 literals and Enum.GetValues<T>().

🤖 Generated with Claude Code