GitNexus/docs/languages/csharp-ingestion-gaps.md

C# Ingestion Gaps

Audited on 2026-10-23 with freshly built production sources at c35806d24 and the accompanying benchmark changes. See the measurement audit for commands, target checks, exclusions and test limits. Historical reports below remain separate from freshly measured receiver cases; broader ingestion is not exhaustively assessed.

Receiver shape snapshot

States below come from baseline.json. The harness defines each spelling and its N/A reason. RESOLVES requires the exact expected declaration ID and no same-named call to a different owner. WRONG-TARGET records incorrect edges.

Shape	Recorded state	Expression or exclusion
plainChain	RESOLVES	svc.GetUser().Save();
plainDeepChain	RESOLVES	svc.GetUser().Address.Save();
optionalChain	RESOLVES	svc?.GetUser().Save();
nonNullAssert	RESOLVES	svc!.GetUser().Save();
awaitParen	RESOLVES	(await svc.GetUserAsync()).Save();
explicitTypeArgs	RESOLVES	svc.GetTyped<User>().Save();
indexElement	VISIBLE-GAP	repos[0].Save();
fieldReceiverCall	RESOLVES	this.repo.Save();
decoratedReceiverBase	N/A	C# this carries no type decoration.
decoratedFieldType	RESOLVES	this.repo.Save();

The matrix resolves local nullable fields and the tested chain wrappers. It still loses repos[0].Save() with a User[] parameter. The resolver already registers an elementTypeOf hook, so this gap needs a full capture-to-resolution trace, not an assumption that the hook is absent.

Planning candidates

ID	Evidence	Gap or boundary	Next planning step and acceptance
CSHARP-01	Measured gap	indexElement remains VISIBLE-GAP for a typed array.	Locate the lost array/type-owner evidence, then assert the exact User.Save target with a same-name decoy and an untyped/unsupported negative.
CSHARP-02	Documented boundary	Qualified nullable fields, including Custom.List<User>?, are refused until their written owner can be proven.	Establish namespace-aware ownership before adding support. Keep wrapper types distinct from element types and preserve external and workspace-tail collision negatives.

Code and regression entry points

• Language provider directory.
• Scope resolver.
• csharp-nullable-field-isolated-ownership.test.ts.
• csharp-nullable-field-generic-arguments.test.ts.
• csharp-namespace-precedence-boundaries.test.ts.

Evidence details: receiver baseline notes and current roadmap.