Source Generator Code Fixes

Preview event-sourcing Reviewed 2026-09-05 purview-dev/eventsourcing

Source Generator Code Fixes

The source-generator package ships IDE code fixes alongside its diagnostics. Fixes live in a separate analyzer assembly (Purview.EventSourcing.SourceGenerator.CodeFixes) so the core Purview.EventSourcing.SourceGenerator assembly never acquires a Microsoft.CodeAnalysis.Workspaces dependency.

Assembly separation

Assembly	Contents	Workspaces dependency
`Purview.EventSourcing.SourceGenerator`	Incremental generators, the analyzer, and all diagnostic descriptors	None
`Purview.EventSourcing.SourceGenerator.CodeFixes`	`CodeFixProvider` implementations that use `DocumentEditor` / `SyntaxGenerator`	Yes (PrivateAssets)

Both assemblies are packed under analyzers/dotnet/cs of Purview.EventSourcing. No Workspaces assembly is shipped in the package and no Workspaces dependency flows into consumer projects. The compiler loads the code-fix assembly without instantiating its Workspaces-dependent types; the IDE activates them for code fixes.

Available fixes

Diagnostic	Fix	Notes
`EVENTSTORE001` (aggregate must be partial)	Adds `partial` to the aggregate declaration	Trivia, nesting, generic parameters, and accessibility preserved
`EVENTSTORE101` (value object must be partial)	Adds `partial` to the value-object declaration	Works for record structs, structs, and classes
`EVENTSTORE007` (event method must be partial)	Adds `partial` to the method
`EVENTSTORE021` (schema version must be positive)	Resets the version to `1`	Only when the version argument is explicit
`EVENTSTORE022` (duplicate schema version)	Moves the version to the next unused version on the aggregate	Only when the version argument is explicit

Fixes use stable equivalence keys and support Fix All where safe. No fix is offered when a correct correction is ambiguous (for example a renamed event contract or an incompatible payload change); the diagnostic message provides guidance instead.

Reference

The fixes share the diagnostic descriptors defined in the source-generator assembly via InternalsVisibleTo; no diagnostic is defined in the code-fix assembly.