# Testing Patterns

Only read this file when creating or modifying tests.

This project uses:

- Vitest
- Playwright browser testing
- Svelte Testing Library patterns through vitest/browser

---

# Test Philosophy

Tests should prove behavior.

Do not write tests that only confirm implementation details.

Every test must contain meaningful assertions.

A test without assertions fails because:

expect.requireAssertions is enabled.

---

# Test Locations

Tests are colocated with source files.

Client tests:

*.svelte.test.ts
*.svelte.spec.ts

Server tests:

*.test.ts
*.spec.ts

---

# Vitest Projects

There are two test environments.

## Client

Used for Svelte components.

Environment:

Playwright Chromium browser.

Used for:

- rendering
- user interaction
- form behavior

---

## Server

Used for:

- load functions
- actions
- server utilities

Environment:

Node.

---

# Before Each Test

Always reset mocks:

beforeEach(() => {
	vi.clearAllMocks();
});

---

# Server Tests

Server route tests should cover:

- authenticated behavior
- unauthenticated behavior
- authorization rules
- successful operations
- failed operations

Mock:

- $lib/db
- authentication helpers
- external services

---

# Prisma Mocking

Mock only the methods used.

Example:

vi.mock('$lib/db', () => ({
	prisma: {
		proclamation: {
			findMany: vi.fn(),
			findUnique: vi.fn(),
			create: vi.fn(),
			update: vi.fn(),
			delete: vi.fn()
		}
	}
}));

Do not create massive unused mocks.

---

# Authentication Testing

Use:

createLocals()

Examples:

Unauthenticated:

createLocals()

Authenticated:

createLocals(mockUser() as any)

Specific roles:

createLocals(
	mockUser({ roleId: 4 }) as any
)

---

# Client Test Locators

Available:

getByRole
getByText
getByPlaceholder
getByAltText
getByTestId

Unavailable:

getByLabel
getByDisplayValue

---

# Role Queries

Always use exact regex names.

Preferred:

page.getByRole(
	'textbox',
	{ name: /^Name$/ }
)

Avoid:

page.getByRole(
	'textbox',
	{ name: 'Name' }
)

because substring matching can create strict-mode failures.

---

# Select Testing

Because selects use selected options instead of bind:value:

const element =
	await page
		.getByRole(
			'combobox',
			{ name: /^Frequency$/ }
		)
		.element();

expect(
	(element as HTMLSelectElement).value
).toBe('2');

---

# Svelte Component Mocking

When mocking Svelte 5 components:

Use:

vi.mock('$lib/components/example.svelte', () => ({
	default: ($anchor: Element) => {
		const div = document.createElement('div');
		$anchor.replaceWith(div);
	}
}));

Imports using mocked modules must come after vi.mock().

If variables are needed inside mocks:

Use vi.hoisted().

---

# Test Completion Rule

After writing tests:

Run:

npm run test

If failures occur:

Fix them.

Do not report "tests added" without verifying they pass.