snapshot of https://github.com/tldraw/tldraw.git (main, 2026-09-23; blobs > 131072B omitted)

apps/dotcom/client/scripts/dev-app.test.ts

@@ -0,0 +1,66 @@
+import { createServer, type Server } from 'net'
+import { afterEach, describe, expect, it } from 'vitest'
+import { assertPortFree, getViteArgs } from './dev-app'
+
+let server: Server | null = null
+
+afterEach(async () => {
+	if (!server) return
+	await new Promise<void>((resolve) => server!.close(() => resolve()))
+	server = null
+})
+
+function listenOnRandomPort(host: string) {
+	return new Promise<number>((resolve, reject) => {
+		server = createServer()
+		server.once('error', reject)
+		server.listen(0, host, () => {
+			const address = server!.address()
+			if (!address || typeof address === 'string') {
+				reject(new Error('Expected a TCP address'))
+				return
+			}
+			resolve(address.port)
+		})
+	})
+}
+
+describe('dev-app script', () => {
+	it('passes strict port args to Vite', () => {
+		expect(getViteArgs('dev')).toEqual(['dev', '--host', '--port', '3000', '--strictPort'])
+		expect(getViteArgs('preview')).toEqual(['preview', '--host', '--port', '3000', '--strictPort'])
+	})
+
+	it('rejects when the requested port is already occupied', async () => {
+		const port = await listenOnRandomPort('0.0.0.0')
+
+		await expect(assertPortFree(port, ['0.0.0.0'])).rejects.toThrow(
+			`Port ${port} is already in use`
+		)
+	})
+
+	it('skips unavailable host families when checking the client port', async () => {
+		const calls: string[] = []
+
+		await expect(
+			assertPortFree(3000, ['::', '0.0.0.0'], async (_port, host) => {
+				calls.push(host)
+				if (host === '::') {
+					throw Object.assign(new Error('IPv6 is not available'), {
+						code: 'EADDRNOTAVAIL',
+					})
+				}
+			})
+		).resolves.toBeUndefined()
+
+		expect(calls).toEqual(['::', '0.0.0.0'])
+	})
+
+	it('rejects unexpected port probe errors', async () => {
+		await expect(
+			assertPortFree(3000, ['0.0.0.0'], async () => {
+				throw Object.assign(new Error('Unexpected probe error'), { code: 'EPERM' })
+			})
+		).rejects.toThrow('Unexpected probe error')
+	})
+})