# Description of Changes
This PR fixes a C# SDK regression where using `Bound` in index filters
could trigger an ambiguous reference compiler error for Local after
upgrading to `v1.11.2`, as reported in
[#3995](https://github.com/clockworklabs/SpacetimeDB/issues/3995).
It also fixes a related warning-spam regression (`CS0436`) where user
projects could see `Local` type conflicts between generated module code
and the `SpacetimeDB.Runtime` assembly.
* Introduced a public `SpacetimeDB.Bound` type so users no longer need
to import `SpacetimeDB.Internal` to use bounds in index filters.
* Kept `SpacetimeDB.Internal.Bound` for compatibility, but added
implicit conversions between `SpacetimeDB.Internal.Bound` and
`SpacetimeDB.Bound`.
* Updated the C# code generator to emit fully-qualified
`global::SpacetimeDB.Bound` in generated index filter signatures,
avoiding `SpacetimeDB.Internal` in public-facing APIs and preventing
name collisions (e.g., `Local`).
* Updated internal runtime bounds helpers (`BTreeIndexBounds<...>`) to
explicitly use `SpacetimeDB.Bound` when constructing range-scan
arguments.
* Updated Codegen snapshot fixtures to match the new generated output
(type name + formatting).
* Fixed codegen output for `ITableView` `static abstract` member
implementations to generate `public static` methods (required for the
generated code to compile).
It also fixes a related warning-spam regression (CS0436) where user
projects could see Local type conflicts between generated module code
and the SpacetimeDB.Runtime assembly.
Additional fix (related to the `Local` reports):
* Removed the runtime assembly’s ownership of `SpacetimeDB.Local`
(introduced more recently than the generated module `Local`) to prevent
`CS0436` duplicate-type warnings. Basically, the runtime’s concrete
`Local`/`ProcedureTxContext` helpers were renamed and made internal so
the code generator remains the sole owner of module-level
`SpacetimeDB.Local`.
Regression coverage:
* Added generator regression assertions to ensure generated code does
not reference `global::SpacetimeDB.Internal.Bound<...>` and does
reference `global::SpacetimeDB.Bound<...>`.
* Added a runtime API regression assertion that `SpacetimeDB.Bound`
exists and is public in the runtime reference.
* Added a regression assertion that `SpacetimeDB.Runtime` does not
define codegen-owned types (e.g. `SpacetimeDB.Local`,
`ProcedureContext`, etc.) to prevent future `CS0436` conflicts.
* Added a “simulated downstream user file” compile check ensuring no
`CS0436` diagnostics occur when user code references
`SpacetimeDB.Local`.
# API and ABI breaking changes
None.
* No schema or wire-format changes.
* The changes are limited to C# type exposure / naming and codegen
output.
* `SpacetimeDB.Internal.Bound` remains usable via implicit conversions
(backwards compatible for existing code).
# Expected complexity level and risk
2 - Low
* Changes are isolated to C# runtime type exposure, codegen type
references, and snapshot updates.
* No runtime behavior changes to index scan encoding/decoding; only
avoids requiring SpacetimeDB.Internal in user code.
# Testing
- [X] Ran:`dotnet test
crates/bindings-csharp/Codegen.Tests/Codegen.Tests.csproj`
- [X] Ran regression tests locally.
Ryan