Testing

How tests are organized and where to look. Read the actual test/ tree to confirm details, since test files change over time.

1. Test Structure

Tests live under test/, organized by purpose:

• test/unit/: core services and utilities
• test/integration/: API surface by feature, with a subdirectory per feature (assertions, describe, it, test, strict assertions, before/after each, wait-for, etc.)
• test/e2e/: CLI workflows, service management, and watch mode
• test/compatibility/: Docker-based multi-version checks
• test/__fixtures__/: scenario fixtures, mirroring the test structure
• test/__utils__/: shared test helpers
• test/__docker__/: Docker infrastructure (compose plus Dockerfiles)

Read the relevant directory to discover the current files. Poku tests itself, so these files also show how describe(), it(), test(), and assert are used in practice.

2. Test Commands

The package.json scripts are the source of truth. The main ones:

• npm test: runs the unit, integration, and e2e suites on Node via tsx
• npm run test:bun: same suites on the Bun runtime
• npm run test:deno: same suites on Deno (with --denoAllow=all)
• npm run test:coverage: runs npm test with the --coverage flag (c8 plus monocart-coverage-reports via @pokujs/c8)
• npm run test:docker:node: runs the Docker compatibility matrix

3. Test Patterns

Open a representative file in the relevant directory to learn the pattern:

• Unit: parallel assertions via Promise.all([it(...)])
• Integration: comprehensive coverage of a single API surface per feature
• E2E: service lifecycle with startService(), waitForPort(), and server.end()
• Compatibility: @pokujs/docker lifecycle to run a suite inside a container

Comments are completely prohibited in tests. describe, it, test, assert, and strict all accept a message, so express intent through those instead.

Prefer value-preserving asserts over a derived boolean. assert(regex.test(x)) collapses failures to Actual: false / Expected: true. assert.match / assert.doesNotMatch print Value + RegExp, and assert.strictEqual / assert.deepStrictEqual print Actual + Expected. Split combined checks like a && b into independent assertions. A boolean assertion is acceptable only when no value-preserving form fits.

A bug-reproduction test asserts the correct expected behavior, so without a fix it MUST fail and pass only once the bug is fixed. Never write it to pass against the buggy behavior.

4. Test Utils (test/__utils__/)

Shared helpers for writing tests:

• inspectPoku(args, configs): run the CLI, capture stdout/stderr/exitCode
• inspectCLI(command, args): generic CLI inspection
• watchCLI(args, configs): monitor watch mode via a getOutput() callback
• legacyFetch(host, port): HTTP fetch for Node 16 compatibility

5. Fixtures (test/__fixtures__/)

Fixtures provide controlled scenarios and mirror the test structure (unit/, integration/, e2e/). They cover cases such as config files, HTTP servers, pass/fail outcomes, fail-fast, file discovery, module types (CJS/ESM/TypeScript), reporters, and watch mode. Read test/__fixtures__/ to find an existing scenario or to add a new one next to its peers.

6. Docker Testing

• Filter the version: FILTER=node-<version> npm run test:docker:node
• Compose file: test/__docker__/docker-compose.yml
• Runs against the built ci/ (NODE_ENV=build, .js)

7. Coverage

• Minimum threshold lives in .nycrc (checkCoverage, the source of truth). The goal is 100%
• Preference: E2E or integration tests for coverage. Use unit tests only for extremely complex or hard-to-reproduce scenarios, such as watch usage