typecheck in CI

.github/workflows/ci.yml

@@ -86,3 +86,4 @@ jobs:
       - run: pnpm install --frozen-lockfile
       - run: pnpm build --filter ./packages
       - run: pnpm lint
+      - run: pnpm check

package.json

@@ -6,6 +6,7 @@
 	"scripts": {
 		"build": "pnpm build --filter=\"@sveltejs/*\" --filter=\"create-svelte\"",
 		"test": "pnpm -r test --workspace-concurrency=1",
+		"check": "pnpm -r check",
 		"lint": "pnpm -r lint",
 		"format": "pnpm -r format",
 		"release": "pnpm publish --tag=next --filter=\"@sveltejs/*\" --filter=\"create-svelte\""

packages/kit/src/core/dev/index.js

@@ -126,7 +126,7 @@ class Watcher extends EventEmitter {
 
 					const rendered = await ssr(
 						{
-							headers: req.headers,
+							headers: /** @type {import('../../../types.internal').Headers} */ (req.headers),
 							method: req.method,
 							host: null,
 							path: parsed.pathname,

packages/kit/src/core/load_config/index.js

@@ -98,7 +98,7 @@ export async function load_config({ cwd = process.cwd() } = {}) {
 }
 
 /**
- * @param {import('../../../../types.internal').Config} config
+ * @param {import('../../../types').Config} config
  * @returns {import('../../../types.internal.js').ValidatedConfig}
  */
 export function validate_config(config) {

packages/kit/src/core/start/index.js

@@ -44,8 +44,9 @@ export async function start({ port, config, cwd = process.cwd() }) {
 				static_handler(req, res, async () => {
 					const rendered = await app.render(
 						{
+							host: `localhost:${port}`,
 							method: req.method,
-							headers: req.headers,
+							headers: /** @type {import('../../../types.internal').Headers} */ (req.headers),
 							path: parsed.pathname,
 							body: await get_body(req),
 							query: new URLSearchParams(parsed.query || '')

packages/kit/src/runtime/server/index.js

@@ -50,6 +50,8 @@ export async function ssr(request, options) {
 
 			return {
 				status: response.status,
+				// TODO header merging is more involved than this — see the 'message.headers'
+				// section of https://nodejs.org/api/http.html#http_class_http_incomingmessage
 				headers: { ...headers, ...response.headers },
 				body: response.body,
 				dependencies: response.dependencies

packages/kit/src/runtime/server/page.js

@@ -43,7 +43,7 @@ async function get_response({ request, options, $session, route, status = 200, e
 
 	/**
 	 * @param {string} url
-	 * @param {import('node-fetch').RequestInit} opts
+	 * @param {RequestInit} opts
 	 */
 	const fetcher = async (url, opts = {}) => {
 		if (options.local && url.startsWith(options.paths.assets)) {
@@ -64,7 +64,7 @@ async function get_response({ request, options, $session, route, status = 200, e
 
 		if (parsed.protocol) {
 			// external fetch
-			response = await fetch(parsed.href, opts);
+			response = await fetch(parsed.href, /** @type {import('node-fetch').RequestInit} */ (opts));
 		} else {
 			// otherwise we're dealing with an internal fetch
 			const resolved = resolve(request.path, parsed.pathname);
@@ -88,7 +88,10 @@ async function get_response({ request, options, $session, route, status = 200, e
 					});
 				} else {
 					// TODO we need to know what protocol to use
-					response = await fetch(`http://${page.host}/${asset.file}`, opts);
+					response = await fetch(
+						`http://${page.host}/${asset.file}`,
+						/** @type {import('node-fetch').RequestInit} */ (opts)
+					);
 				}
 			}
 
@@ -97,7 +100,7 @@ async function get_response({ request, options, $session, route, status = 200, e
 					{
 						host: request.host,
 						method: opts.method || 'GET',
-						headers: opts.headers || {}, // TODO inject credentials...
+						headers: /** @type {import('../../../types.internal').Headers} */ (opts.headers || {}), // TODO inject credentials...
 						path: resolved,
 						body: opts.body,
 						query: new URLSearchParams(parsed.query || '')

packages/kit/types.d.ts

@@ -1,4 +1,4 @@
-import { LoadInput, LoadOutput, Logger } from './types.internal';
+import { Headers, LoadInput, LoadOutput, Logger } from './types.internal';
 
 export type Config = {
 	compilerOptions?: any;
@@ -56,7 +56,7 @@ interface ReadOnlyFormData extends Iterator<[string, string]> {
 export type RequestHandler = (
 	request?: {
 		host: string;
-		headers: Record<string, string>;
+		headers: Headers;
 		path: string;
 		params: Record<string, string>;
 		query: URLSearchParams;

packages/kit/types.internal.d.ts

@@ -59,6 +59,10 @@ export type App = {
 	render: (request: Request, options: SSRRenderOptions) => Response;
 };
 
+// TODO we want to differentiate between request headers, which
+// always follow this type, and response headers, in which
+// 'set-cookie' is a `string[]` (or at least `string | string[]`)
+// but this can't happen until TypeScript 4.3
 export type Headers = Record<string, string>;
 
 export type Request = {
@@ -67,7 +71,6 @@ export type Request = {
 	headers: Headers;
 	path: string;
 	body: any;
-	params: Record<string, string>;
 	query: URLSearchParams;
 };
 
@@ -156,6 +159,7 @@ export type SSRManifest = {
 	endpoints: Endpoint[];
 };
 
+// TODO separate out runtime options from the ones fixed in dev/build
 export type SSRRenderOptions = {
 	paths?: {
 		base: string;
@@ -174,15 +178,15 @@ export type SSRRenderOptions = {
 			context?: any;
 			headers?: Headers;
 		};
-		getSession: ({ context }: { context: any }) => any;
+		getSession?: ({ context }: { context: any }) => any;
 	};
 	dev?: boolean;
 	amp?: boolean;
 	only_prerender?: boolean;
 	app_dir?: string;
 	host?: string;
 	host_header?: string;
-	get_component_path: (id: string) => string;
+	get_component_path?: (id: string) => string;
 	get_stack?: (error: Error) => string;
 	get_static_file?: (file: string) => Buffer;
 	get_amp_css?: (dep: string) => string;