菜单
Use when writing a Rust test that exercises a failure path or a MASM test that expects a `panic` / `assert` — assert on the specific expected error variant or error code.
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基于 SOC 职业分类
| name | assert-specific-error-in-tests |
| description | Use when writing a Rust test that exercises a failure path or a MASM test that expects a `panic` / `assert` — assert on the specific expected error variant or error code. |
A test that exercises an error path must assert on the specific error returned:
assert_matches!(result, Err(MyError::SpecificVariant { .. })) or destructure the error and assert on its fields. Don't accept "any Err" via assert!(result.is_err()).ERR_* constant, not just that the transaction failed.If multiple error conditions could plausibly fire on the same input, assert on the one this test is actually exercising.
A test that only checks is_err() passes even when an unrelated bug breaks the function, so it no longer validates the failure mode it claims to. Pinning the exact variant also catches reorderings where one error path starts firing instead of another.
// Good
use assert_matches::assert_matches;
let result = AccountId::try_from(&bytes);
assert_matches!(result, Err(AccountError::InvalidLength { expected: 32, got: 5 }));
// Bad
let result = AccountId::try_from(&bytes);
assert!(result.is_err());
// Good (MASM test)
let err = run_kernel(...).unwrap_err();
assert_eq!(err.code(), ERR_NOTE_NOT_FOUND);
// Bad
assert!(run_kernel(...).is_err());
Enforce type-signature conventions for public Miden Assembly (.masm) procedures. Use when adding, editing, or reviewing a `pub proc` signature — parameter and return types, semantic type aliases, struct/array/tuple types, and how the signature maps onto the operand stack and the doc-comment Inputs/Outputs.
Enforce inline commenting conventions for Miden Assembly (.masm) files. Use when editing, reviewing, or creating .masm files.
Enforce doc comment conventions for Miden Assembly (.masm) procedures. Use when editing, reviewing, or creating .masm procedures, especially when documenting inputs, outputs, panic conditions, or invocation types.
Use when writing kernel, account, or note MASM code that reads from or writes to the advice provider (advice stack / advice map) — validate advice data.
Use when writing or reviewing MASM hot paths — prefer the cheaper equivalent instruction: `neq.0` over `gt.0` for non-zero checks, `cdrop` over an `if/else` selecting between two values, `dup.N` over `loc_load` for a value still on the stack, `eqw` over element-wise word comparison, `u32gt`/`u32lt` over generic `gt`/`lt` on known-u32 operands.
Use when writing Rust arithmetic on amounts or other quantities derived from external/user input — guard against silent overflow.