Tests should follow consistent structure and provide high-signal coverage. Apply these rules: 1) Put tests in dedicated files - Follow the repo convention: place unit tests in separate `*_tests.rs` (or `*_test.rs`) files, not inline `#[cfg(test)] mod tests { ... }` blocks. - Avoid inserting test modules between import statements. If you need a separate file but want to keep the module declaration local, use `#[path = "..."] mod tests;`. Example pattern: ```rust // in source file #[cfg(test)] #[path = "my_module_tests.rs"] mod tests; ``` 2) Keep tests concise and behavior-focused - Don’t add verbose scaffolding when a test only needs to prove one meaningful behavior (e.g., “override/clear works”). 3) Consolidate related checks into regression-style tests - When covering a previously reported bug, consolidate to a single regression test and add a comment pointing to the issue/PR (e.g., `// regression for #10139`). 4) Assert complete, observable sequences - If logic triggers multiple events (e.g., press + release routing), the test should assert the full sequence rather than only the first effect. 5) Ensure cross-platform coverage when you condition tests - If tests are excluded on Windows (or made platform-dependent), add Windows-specific unit tests to validate the same behavior/round-trip semantics. These practices improve maintainability, reduce test brittleness, and ensure coverage remains accurate as behavior evolves.