The repo is a Yarn workspaces monorepo. Core runtime logic shared primitives and shared primitives live in packages/core/src, and individual prompt implementations under packages/<prompt>/src. Testing utilities sit in packages/testing, while packages/demo provides the interactive showcase. Integration suites reside in integration/cjs and integration/esm to verify bundling. Tooling scripts live in tools/ and repo wiring (tsconfig, release helpers) in internals/. Treat packages/*/dist as generated output.
Install deps with yarn install. Use yarn dev for Turbo-powered incremental TypeScript builds. Launch the playground with yarn demo. Run yarn tsc for a project-wide compile. Execute yarn pretest for lint, format, and type gates, then yarn test for Vitest unit coverage followed by Node integration tests. After adding or moving workspaces, run yarn setup to refresh shared TS references.
Code is ESM-first TypeScript targeting Node ≥ 18. Prettier enforces two-space indentation, trailing commas, and single quotes—lean on it rather than hand formatting. Prefer named exports, keep prompt IDs aligned with folder names, and store assets beside their entry points. Use camelCase for variables/functions and PascalCase for classes/components. Run yarn oxlint --fix and yarn eslint --fix before committing to maintain rule compliance.
Prioritize type safety and leverage existing types from the codebase. Use Question<A> from packages/inquirer/src/types.ts instead of generic Record<string, unknown> when working with question objects. Prefer unknown over any for truly unknown types, and use Partial<T> for optional properties. Leverage generic type parameters (like <A extends Answers>) throughout to maintain type consistency. Avoid eslint-disable comments by refactoring to proper types rather than suppressing warnings. When extending types, use intersection types (Type & { prop: T }) for explicit signatures rather than casting to any.
Vitest owns unit coverage via vitest.config.ts, with coverage.all = true so untested files fail CI. Co-locate specs as *.test.ts next to source, and model cross-package flows under integration/**/**/*.test.ts. Iterate with yarn vitest --run packages, then finish with yarn test to exercise the full matrix. Update snapshots using yarn vitest --update.
Keep tests simple and focused. Reuse existing test stubs and fixtures rather than creating custom mocks. If a behavior affects all prompts, test it with an existing prompt type rather than creating a specialized stub. Write tests that verify actual behavior rather than implementation details. Prefer straightforward assertions over complex validation logic.
Follow Conventional Commit prefixes such as feat:, fix:, docs:, or chore:; keep scopes lowercase (feat(@inquirer/package-name): add fuzzy search). Summaries should stay imperative and under 80 characters. Pull requests must describe the change, list the commands run (for example yarn test), and link issues or discussions. Attach terminal recordings or screenshots for UX-facing changes, and ensure lockfiles and generated readme fragments stay current.