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name: testing description: Policies for unit testing, E2E testing, and test-running constraints for DBConvert Streams UI.

Testing (Agent & Copilot Rules)

Scope

• Prefer unit tests (Vitest) by default.
• E2E tests (Playwright) are out of scope unless explicitly requested.
• Do not assume the dev server is running unless the user says it is.

Commands (Preferred)

• Unit tests: yarn test:unit
• Lint/build checks (often faster signal): yarn lint, yarn build
• E2E tests: yarn test / yarn test:headed / yarn test:ui (only when asked)

Critical Constraints

• Never run yarn dev automatically. The maintainer starts the dev server manually.
• Use Yarn only (no npm). Node >= 22 is required.

Test Locations

• Unit tests: src/__tests__/
• Playwright E2E: tests/ (auth state: tests/.auth/user.json is not committed)

Adding/Changing Tests

• Add/update unit tests for new behavior where practical.
• Keep tests focused; avoid fragile timing-based assertions.
• Prefer testing public behavior over implementation details.

Developer How-To

For developer-facing setup and step-by-step commands, see TESTING.md.