Testing

Test WildflowerJS components with confidence using our official test utilities package.

@wildflowerjs/test-utils

The official testing utilities package provides everything you need to test WildflowerJS applications:

• Framework loading - Load source or distribution builds
• State isolation - Clean slate between tests
• Timing utilities - Wait for reactive updates correctly
• Vitest integration - Automatic setup with hooks
• TypeScript support - Full type definitions included

Installation

npm install @wildflowerjs/test-utils --save-dev

Quick Start

The Easy Way: setupWildflowerTests()

For most tests, use the automatic setup helper:

import { describe, it, expect } from 'vitest'
import { setupWildflowerTests, waitForUpdate } from '@wildflowerjs/test-utils/vitest'

describe('Counter Component', () => {
    const { getContainer, getWildflower } = setupWildflowerTests()

    it('should increment count when button clicked', async () => {
        const wildflower = getWildflower()
        const container = getContainer()

        // Register component
        wildflower.component('counter', {
            state: { count: 0 },
            increment() {
                this.count++
            }
        })

        // Set up DOM
        container.innerHTML = `
            <div data-component="counter">
                <span id="count-display" data-bind="count"></span>
                <button data-action="increment">+</button>
            </div>
        `

        // Initialize
        wildflower.scan()
        await waitForUpdate()

        // Assert initial state (use id, not [data-bind]: attributes are stripped after binding)
        expect(container.querySelector('#count-display').textContent).toBe('0')

        // Trigger action
        container.querySelector('button').click()
        await waitForUpdate()

        // Assert updated state
        expect(container.querySelector('#count-display').textContent).toBe('1')
    })
})

setupWildflowerTests() automatically handles:

• Loading the framework (beforeAll)
• Resetting state between tests (beforeEach)
• Creating and cleaning up test containers
• Reinitializing the context system

Manual Setup

For more control, set up the test environment manually:

import { describe, it, expect, beforeAll, beforeEach, afterEach } from 'vitest'
import {
    loadFramework,
    resetFramework,
    waitForUpdate,
    waitForCompleteRender,
    createTestContainer,
    initContextSystem
} from '@wildflowerjs/test-utils'

describe('My Component', () => {
    let container, cleanup

    beforeAll(async () => {
        await loadFramework()
    })

    beforeEach(() => {
        resetFramework()
        initContextSystem()
        const result = createTestContainer()
        container = result.container
        cleanup = result.cleanup
    })

    afterEach(() => {
        cleanup()
    })

    it('should work', async () => {
        // Your test here
    })
})

Mounting Components

mountComponent()

Quick way to mount a component for testing:

import { mountComponent } from '@wildflowerjs/test-utils/vitest'

it('should display user name', async () => {
    const { instance, element, cleanup } = await mountComponent(
        'user-card',
        {
            state: { name: 'Alice', role: 'Admin' }
        },
        `<div data-component="user-card">
            <h2 data-bind="name"></h2>
            <span data-bind="role"></span>
        </div>`
    )

    expect(element.querySelector('h2').textContent).toBe('Alice')
    expect(element.querySelector('span').textContent).toBe('Admin')

    cleanup()
})

createTestHarness()

Fluent API for building test components:

import { createTestHarness } from '@wildflowerjs/test-utils/vitest'

it('should calculate total', async () => {
    const { instance, element } = await createTestHarness('calculator')
        .withState({ price: 100, quantity: 2 })
        .withComputed({
            total() {
                return this.price * this.quantity
            }
        })
        .withTemplate(`
            <div data-component="calculator">
                <span data-bind="total"></span>
            </div>
        `)
        .mount()

    expect(element.querySelector('span').textContent).toBe('200')
})

Timing Utilities

WildflowerJS uses reactive updates that happen asynchronously. Always wait after state changes:

import { waitForUpdate, waitForCompleteRender, waitForState } from '@wildflowerjs/test-utils'

// After state change
instance.count++
await waitForUpdate()

// After scanning for components
wildflower.scan()
await waitForCompleteRender()

// Waiting for async operation
instance.fetchData()  // Sets loading = true, then false
await waitForState(instance, 'loading', false, 2000)

Testing Patterns

Testing State Changes

it('should update display when state changes', async () => {
    const { getContainer, getWildflower } = setupWildflowerTests()
    const wildflower = getWildflower()
    const container = getContainer()

    wildflower.component('greeting', {
        state: { message: 'Hello' }
    })

    container.innerHTML = `
        <div data-component="greeting">
            <span data-bind="message"></span>
        </div>
    `

    wildflower.scan()
    await waitForCompleteRender()

    // Get instance
    const element = container.querySelector('[data-component="greeting"]')
    const instance = wildflower.componentInstances.get(element.dataset.componentId)

    // Verify initial state
    expect(container.querySelector('span').textContent).toBe('Hello')

    // Change state
    instance.message = 'Goodbye'
    await waitForUpdate()

    // Verify DOM updated
    expect(container.querySelector('span').textContent).toBe('Goodbye')
})

Testing Lists

it('should render and update list items', async () => {
    const { instance, element } = await mountComponent(
        'todo-list',
        {
            state: {
                items: [
                    { text: 'First' },
                    { text: 'Second' }
                ]
            },
            addItem(text) {
                this.items.push({ text })
            }
        },
        `<div data-component="todo-list">
            <ul data-list="items">
                <template>
                    <li data-bind="text"></li>
                </template>
            </ul>
        </div>`
    )

    // Initial render
    expect(element.querySelectorAll('li').length).toBe(2)

    // Add item
    instance.addItem('Third')
    await waitForUpdate()

    expect(element.querySelectorAll('li').length).toBe(3)
    expect(element.querySelectorAll('li')[2].textContent).toBe('Third')
})

Testing Conditionals

it('should toggle visibility with data-show', async () => {
    const { instance, element } = await mountComponent(
        'toggle',
        { state: { isVisible: false } },
        `<div data-component="toggle">
            <div data-show="isVisible" class="content">Content</div>
        </div>`
    )

    const content = element.querySelector('.content')

    // Initially hidden
    expect(content.style.display).toBe('none')

    // Show it
    instance.isVisible = true
    await waitForUpdate()

    expect(content.style.display).not.toBe('none')
})

Testing Form Inputs

it('should two-way bind with data-model', async () => {
    const { instance, element } = await mountComponent(
        'form-test',
        { state: { username: '' } },
        `<div data-component="form-test">
            <input type="text" data-model="username">
            <span data-bind="username"></span>
        </div>`
    )

    const input = element.querySelector('input')
    const display = element.querySelector('span')

    // Simulate user typing
    input.value = 'john_doe'
    input.dispatchEvent(new Event('input', { bubbles: true }))
    await waitForUpdate()

    // State and display should update
    expect(instance.username).toBe('john_doe')
    expect(display.textContent).toBe('john_doe')
})

Testing Stores

it('should share state via stores', async () => {
    const wildflower = getWildflower()

    // Create store
    wildflower.store('userStore', {
        state: { name: 'Guest' },
        setName(name) {
            this.name = name
        }
    })

    // Component using store
    const { element } = await mountComponent(
        'user-display',
        {
            state: {},
            external() {
                return { user: 'store:userStore' }
            }
        },
        `<div data-component="user-display">
            <span data-bind="external:user.name"></span>
        </div>`
    )

    expect(element.querySelector('span').textContent).toBe('Guest')

    // Update store
    const store = wildflower.storeManager.getStore('userStore')
    store.setName('Alice')
    await waitForUpdate()

    expect(element.querySelector('span').textContent).toBe('Alice')
})

Testing Different Builds

Test your code against different framework builds:

# Test against minified core build
WILDFLOWER_DIST=core npx vitest run

# Test against lite build (fewer features)
WILDFLOWER_DIST=lite npx vitest run

# Test against full build with SSR
WILDFLOWER_DIST=full npx vitest run

Use feature detection to skip tests that require unavailable features:

import { hasFeature, skipIfNoFeature } from '@wildflowerjs/test-utils'

it('should use portals', skipIfNoFeature('portals', async () => {
    // Only runs if portals are available (not in lite build)
}))

// Or check manually
if (hasFeature('ssr')) {
    // Test SSR functionality
}

Common Pitfalls

// WRONG - No wait after state change
instance.count++
expect(element.textContent).toBe('1')  // Fails!

// CORRECT
instance.count++
await waitForUpdate()
expect(element.textContent).toBe('1')

// WRONG - Bindings won't work
beforeEach(() => {
    resetFramework()
    // Missing initContextSystem()!
})

// CORRECT
beforeEach(() => {
    resetFramework()
    initContextSystem()
})

// WRONG - May not be enough time
wildflower.scan()
await waitForUpdate()

// CORRECT
wildflower.scan()
await waitForCompleteRender()

AI Testing Guide

The test-utils package includes a comprehensive AI Testing Guide (AI_TESTING_GUIDE.md) designed to help AI assistants generate high-quality tests. It includes:

• Standard test file templates
• 15+ "How to Test X" recipes
• Timing utilities cheat sheet
• Common pitfalls with solutions
• Assertion best practices
• Quick reference card

When asking an AI assistant to write tests for your WildflowerJS components, reference this guide for idiomatic, working tests.

API Reference

Core Utilities

Vitest Integration

Build Detection

Vitest Configuration

Browser Mode (Recommended)

For accurate DOM behavior, use Vitest's browser mode:

// vitest.browser.config.js
import { defineConfig } from 'vitest/config'

export default defineConfig({
    test: {
        browser: {
            enabled: true,
            provider: 'playwright',
            name: 'chromium',
            headless: true
        },
        include: ['test/**/*.test.js']
    }
})

jsdom (Faster, Less Accurate)

For faster tests that don't need full browser APIs:

// vitest.config.js
import { defineConfig } from 'vitest/config'

export default defineConfig({
    test: {
        environment: 'jsdom',
        include: ['test/**/*.test.js']
    }
})

Running Tests

# Run all tests
npx vitest run

# Watch mode
npx vitest

# Specific file
npx vitest run test/counter.test.js

# Pattern matching
npx vitest run -t "should increment"

# With coverage
npx vitest run --coverage

# Verbose output
npx vitest run --reporter=verbose