borrowEnv(overrides: Record<string, string | undefined>): Disposable
Applies overrides over process.env for the scope, then restores it exactly: keys added
during the scope are dropped and changed values are put back.
Key-by-key rather than process.env = snapshot, because assigning the object wholesale
replaces the live binding other modules may already hold a reference to.
import { borrowEnv } from './borrowed-globals.ts'; { using _env = borrowEnv({ QUNITX_BORROW_EXAMPLE: '1' }); process.env.QUNITX_BORROW_EXAMPLE; // '1' } process.env.QUNITX_BORROW_EXAMPLE; // undefined — the key never existed, so it is dropped