overhaul tests

test/apps/AppRunner.ts

@@ -0,0 +1,122 @@
+import * as path from 'path';
+import * as puppeteer from 'puppeteer';
+import * as ports from 'port-authority';
+import { fork, ChildProcess } from 'child_process';
+
+declare const start: () => Promise<void>;
+declare const prefetchRoutes: () => Promise<void>;
+declare const prefetch: (href: string) => Promise<void>;
+declare const goto: (href: string) => Promise<void>;
+
+export class AppRunner {
+	cwd: string;
+	entry: string;
+	port: number;
+	proc: ChildProcess;
+	messages: any[];
+
+	browser: puppeteer.Browser;
+	page: puppeteer.Page;
+
+	constructor(cwd: string, entry: string) {
+		this.cwd = cwd;
+		this.entry = path.join(cwd, entry);
+		this.messages = [];
+	}
+
+	async start() {
+		this.port = await ports.find(3000);
+
+		this.proc = fork(this.entry, [], {
+			cwd: this.cwd,
+			env: {
+				PORT: String(this.port)
+			}
+		});
+
+		this.proc.on('message', message => {
+			if (!message.__sapper__) return;
+			this.messages.push(message);
+		});
+
+		this.browser = await puppeteer.launch({ args: ['--no-sandbox'] });
+
+		this.page = await this.browser.newPage();
+		this.page.on('console', msg => {
+			const text = msg.text();
+
+			if (!text.startsWith('Failed to load resource')) {
+				console.log(text);
+			}
+		});
+
+		return {
+			page: this.page,
+			base: `http://localhost:${this.port}`,
+
+			// helpers
+			start: () => this.page.evaluate(() => start()),
+			prefetchRoutes: () => this.page.evaluate(() => prefetchRoutes()),
+			prefetch: (href: string) => this.page.evaluate((href: string) => prefetch(href), href),
+			goto: (href: string) => this.page.evaluate((href: string) => goto(href), href)
+		};
+	}
+
+	capture(fn: () => any): Promise<string[]> {
+		return new Promise((fulfil, reject) => {
+			const requests: string[] = [];
+			const pending: Set<string> = new Set();
+			let done = false;
+
+			function handle_request(request: puppeteer.Request) {
+				const url = request.url();
+				requests.push(url);
+				pending.add(url);
+			}
+
+			function handle_requestfinished(request: puppeteer.Request) {
+				const url = request.url();
+				pending.delete(url);
+
+				if (done && pending.size === 0) {
+					cleanup();
+					fulfil(requests);
+				}
+			}
+
+			function handle_requestfailed(request: puppeteer.Request) {
+				cleanup();
+				reject(new Error(`failed to fetch ${request.url()}`))
+			}
+
+			const cleanup = () => {
+				this.page.removeListener('request', handle_request);
+				this.page.removeListener('requestfinished', handle_requestfinished);
+				this.page.removeListener('requestfailed', handle_requestfailed);
+			};
+
+			this.page.on('request', handle_request);
+			this.page.on('requestfinished', handle_requestfinished);
+			this.page.on('requestfailed', handle_requestfailed);
+
+			return Promise.resolve(fn()).then(() => {
+				if (pending.size === 0) {
+					cleanup();
+					fulfil(requests);
+				}
+
+				done = true;
+			});
+		});
+	}
+
+	end() {
+		return Promise.all([
+			this.browser.close(),
+			new Promise(fulfil => {
+				this.proc.once('exit', fulfil);
+				this.proc.kill();
+			})
+		]);
+	}
+}