Cargo Tester: Pre-made File Loader Refactoring

[AndrewF001]

Proposal

The Tester cargo is intended to make testing easier & standardized. The feature in question is the loading of pre-made P4 files. Current implementation is a built in-house with fs::read_to_string and loads files dynamically from a resource folder based on a file name or array index. The proposed change is to swap to resource_str macro.

Pros

• Not built in-house, so can rely on it
• Can load files statically

Cons

• Files could be large for them to be stored statically
• CRLF/LF formatting behavior (discussed below)

Other

There is a lack of standard for line endings in LSP 1.7 and Wasm which has created a platform-specific discrepancies between files for whether to use CRLF or LF. Because of this, I believe the testing process should support both to iron out parser bugs!

In the future I would also like to add an extra confirmation stage to the CI/CD that given the same files P4 analyzer can spot compiler errors the same as P4 compiler. This issues shouldn't affect the prospect of this but something to be mindful of.