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Write E2e Tests Agent Skill

Writing Playwright E2E tests for tldraw. Use when creating browser tests, testing UI interactions, or adding E2E coverage in apps/examples/e2e or apps/dotcom/client/e2e.

2k tokens
context cost
the whole folder, loaded on every use
1
files
instructions only
0
copies elsewhere
how many repositories repackaged it
49579
stars on the repo
on the repository, not the skill itself

Install

one command, takes just this skill from the repository
npx skills add https://github.com/tldraw/tldraw --skill write-e2e-tests

The instruction itself

25 sections, as written by the author

Writing E2E tests

E2E tests use Playwright. Located in apps/examples/e2e/ (SDK examples) and apps/dotcom/client/e2e/ (tldraw.com).

Test file structure

apps/examples/e2e/
├── fixtures/
│   ├── fixtures.ts        # Test fixtures (toolbar, menus, etc.)
│   └── menus/             # Page object models
├── tests/
│   └── test-*.spec.ts     # Test files
└── shared-e2e.ts          # Shared utilities

Name test files test-<feature>.spec.ts.

Required declarations

When using page.evaluate() to access the editor or UI events:

import { Editor } from 'tldraw'

declare const editor: Editor
declare const __tldraw_ui_event: { name: string; data?: any }

Basic test structure

import { expect } from '@playwright/test'
import test from '../fixtures/fixtures'
import { setupOrReset } from '../shared-e2e'

test.describe('Feature name', () => {
	test.beforeEach(setupOrReset)

	test('does something', async ({ page, toolbar }) => {
		// Test implementation
	})
})

Setup patterns

test.beforeEach(setupOrReset) // Smart: navigates first run, fast reset after

Shared page for performance

For tests that don't need full isolation:

let page: Page

test.describe('Feature', () => {
	test.beforeAll(async ({ browser }) => {
		page = await browser.newPage()
		await setupPage(page)
	})

	test.beforeEach(async () => {
		await hardResetEditor(page)
	})
})

Setup with shapes

import { setupPageWithShapes, hardResetWithShapes } from '../shared-e2e'

test.beforeEach(async ({ browser }) => {
	if (!page) {
		page = await browser.newPage()
		await setupPage(page)
	} else {
		await hardResetEditor(page)
	}
	await setupPageWithShapes(page)
})

Available fixtures

test('example', async ({
	page, // Playwright page
	toolbar, // Toolbar page object
	stylePanel, // Style panel
	actionsMenu, // Actions menu
	mainMenu, // Main menu
	pageMenu, // Page menu
	navigationPanel, // Navigation panel
	richTextToolbar, // Rich text toolbar
	api, // tldrawApi methods
	isMobile, // Mobile viewport check
	isMac, // Mac platform check
}) => {})

Interacting with the editor

Via page.evaluate

// Execute code in browser context
await page.evaluate(() => {
	editor.createShapes([{ type: 'geo', x: 100, y: 100, props: { w: 100, h: 100 } }])
})

// Fast reset (faster than keyboard shortcuts)
await page.evaluate(() => {
	editor.selectAll().deleteShapes(editor.getSelectedShapeIds())
	editor.setCurrentTool('select')
})

// Get data from editor
const shape = await page.evaluate(() => editor.getOnlySelectedShape())
expect(shape).toMatchObject({ type: 'geo', x: 100, y: 100 })

Testing UI events

await page.keyboard.press('Control+a')
expect(await page.evaluate(() => __tldraw_ui_event)).toMatchObject({
	name: 'select-all-shapes',
	data: { source: 'kbd' },
})

Selecting tools and UI elements

By test ID

await page.getByTestId('tools.rectangle').click()
await page.getByTestId('tools.more.cloud').click() // In popover
await expect(page.getByTestId('tools.select')).toHaveAttribute('aria-pressed', 'true')

Via toolbar fixture

const { select, draw, arrow, rectangle } = toolbar.tools
await rectangle.click()
await toolbar.isSelected(rectangle)
await toolbar.isNotSelected(select)

// More tools popover
await toolbar.moreToolsButton.click()
await toolbar.popOverTools.popoverCloud.click()
import { clickMenu, withMenu } from '../shared-e2e'

// Click a menu item
await clickMenu(page, 'main-menu.edit.copy')
await clickMenu(page, 'context-menu.copy-as.copy-as-png')

// Focus and interact with menu item
await page.mouse.click(200, 200, { button: 'right' })
await withMenu(page, 'context-menu.arrange.distribute-horizontal', (item) => item.focus())
await page.keyboard.press('Enter')

Data-driven tests

const tools = [
	{ tool: 'rectangle', shape: 'geo' },
	{ tool: 'arrow', shape: 'arrow' },
	{ tool: 'draw', shape: 'draw' },
]

test('creates shapes with tools', async ({ page, toolbar }) => {
	for (const { tool, shape } of tools) {
		await page.getByTestId(`tools.${tool}`).click()
		await page.mouse.click(200, 200)
		expect(await getAllShapeTypes(page)).toContain(shape)

		// Reset for next iteration
		await page.evaluate(() => {
			editor.selectAll().deleteShapes(editor.getSelectedShapeIds())
		})
	}
})

Platform-specific handling

Modifier keys

test('copy paste', async ({ page, isMac }) => {
	const modifier = isMac ? 'Meta' : 'Control'
	await page.keyboard.down(modifier)
	await page.keyboard.press('KeyC')
	await page.keyboard.press('KeyV')
	await page.keyboard.up(modifier)
})

Skip on mobile

test('desktop only feature', async ({ isMobile }) => {
	if (isMobile) return
	// Desktop-specific test
})

Helper functions

import { getAllShapeTypes, getAllShapeLabels, sleep, sleepFrames } from '../shared-e2e'

// Get shape types on canvas
const shapes = await getAllShapeTypes(page)
expect(shapes).toEqual(['geo', 'arrow'])

// Wait for async operations
await sleep(100)
await sleepFrames(2) // Wait for animation frames

Assertions

// Shape assertions
expect(await page.evaluate(() => editor.getOnlySelectedShape())).toMatchObject({
	type: 'geo',
	props: { w: 100, h: 100 },
})

// Attribute assertions
await expect(page.getByTestId('tools.select')).toHaveAttribute('aria-pressed', 'true')

// CSS assertions (for selection state)
await expect(tool).toHaveCSS('color', 'rgb(255, 255, 255)')

// Visibility
await expect(toolbar.moreToolsPopover).toBeVisible()
await expect(toolbar.toolLock).toBeHidden()

Skipping flaky tests

test.describe.skip('clipboard tests', () => {
	// Skipped because flaky in CI
})

test.skip('known issue', async () => {})

Running E2E tests

yarn e2e                    # Examples E2E
yarn e2e-dotcom            # Dotcom E2E
yarn e2e-ui                # With Playwright UI
yarn e2e -- --grep "toolbar"  # Filter by pattern

Key patterns summary

  • Use setupOrReset in beforeEach for test isolation
  • Declare editor and __tldraw_ui_event for page.evaluate()
  • Use page.evaluate() for fast editor manipulation (faster than keyboard)
  • Use getByTestId() with tools.<name> pattern for tool selection
  • Use clickMenu() / withMenu() for menu interactions
  • Handle platform differences with isMac and isMobile fixtures
  • Test against localhost:5420/end-to-end example

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