testing-bunlisted

# Testing with Bun REQUIRED: fetch the [Bun mocks documentation](https://bun.com/docs/test/mocks.md) before writing or modifying tests. ## Running the suite Run the full suite via `bun run test`, never `bun test` directly. The script passes `--isolate`, which runs each test file in its own worker. Without it, `mock.module()` calls leak across files and tests fail in confusing, order-dependent ways. For ad-hoc single-file runs, use `bun test --isolate <file>`. ## Mock helpers Prefer the specific mock helpers over `mockImplementation`: - `mockResolvedValue(value)` / `mockResolvedValueOnce(value)` — async functions returning a value. - `mockRejectedValue(error)` / `mockRejectedValueOnce(error)` — async functions that throw. - `mockReturnValue(value)` / `mockReturnValueOnce(value)` — sync functions. Only reach for `mockImplementation` when behavior depends on arguments or call count. Set mock return values close to the test that asserts on them, with the concrete value the test needs. Indirection through shared variables or transformations makes tests harder to read. ## Spying on object methods Never reassign properties on global or imported objects to stub them — use `spyOn`. Re-spy in `beforeEach` so each test starts from a known state. ```ts // Good — spy, scoped to the test that needs it import { spyOn } from "bun:test"; // Bad — reassigns the property const original = Bun.stdin; beforeEach(() => { // @ts-expect-error Bun.stdin = { json: () => Promise.resolve