chore: use @sveltejs/eslint-config (#9977)

.eslintrc.json

@@ -1,15 +1,11 @@
 {
+	"root": true,
+	"extends": "@sveltejs",
 	"env": {
 		"es2022": true
 	},
-	"parserOptions": {
-		"ecmaVersion": "latest",
-		"sourceType": "module"
-	},
-	"plugins": ["unicorn"],
-	"root": true,
 	"ignorePatterns": ["packages/create-svelte/shared/"],
 	"rules": {
-		"unicorn/prefer-node-protocol": "error"
+		"no-undef": "off"
 	}
 }

package.json

@@ -31,9 +31,13 @@
 		"@rollup/plugin-commonjs": "^25.0.0",
 		"@rollup/plugin-json": "^6.0.0",
 		"@rollup/plugin-node-resolve": "^15.0.1",
+		"@sveltejs/eslint-config": "^6.0.2",
 		"@svitejs/changesets-changelog-github-compact": "^1.1.0",
 		"@typescript-eslint/eslint-plugin": "^5.53.0",
-		"eslint": "^8.33.0",
+		"eslint": "^8.40.0",
+		"eslint-config-prettier": "^8.8.0",
+		"eslint-plugin-import": "^2.27.5",
+		"eslint-plugin-svelte": "^2.28.0",
 		"eslint-plugin-unicorn": "^47.0.0",
 		"playwright": "1.30.0",
 		"prettier": "^2.8.0",

packages/adapter-cloudflare/index.js

@@ -71,15 +71,15 @@ export default function (options = {}) {
  */
 function get_routes_json(builder, assets, { include = ['/*'], exclude = ['<all>'] }) {
 	if (!Array.isArray(include) || !Array.isArray(exclude)) {
-		throw new Error(`routes.include and routes.exclude must be arrays`);
+		throw new Error('routes.include and routes.exclude must be arrays');
 	}
 
 	if (include.length === 0) {
-		throw new Error(`routes.include must contain at least one route`);
+		throw new Error('routes.include must contain at least one route');
 	}
 
 	if (include.length > 100) {
-		throw new Error(`routes.include must contain 100 or fewer routes`);
+		throw new Error('routes.include must contain 100 or fewer routes');
 	}
 
 	exclude = exclude

packages/adapter-node/index.js

@@ -71,7 +71,7 @@ export default function (opts = {}) {
 				dir: `${out}/server`,
 				format: 'esm',
 				sourcemap: true,
-				chunkFileNames: `chunks/[name]-[hash].js`
+				chunkFileNames: 'chunks/[name]-[hash].js'
 			});
 
 			builder.copy(files, out, {

packages/adapter-vercel/index.js

@@ -224,7 +224,7 @@ const plugin = function (defaults = {}) {
 
 			if (ignored_isr.size) {
 				builder.log.warn(
-					`\nWarning: The following routes have an ISR config which is ignored because the route is prerendered:`
+					'\nWarning: The following routes have an ISR config which is ignored because the route is prerendered:'
 				);
 
 				for (const ignored of ignored_isr) {
@@ -586,7 +586,7 @@ function validate_vercel_json(builder, vercel_config) {
 
 	if (unmatched_paths.length) {
 		builder.log.warn(
-			`\nWarning: vercel.json defines cron tasks that use paths that do not correspond to an API route with a GET handler (ignore this if the request is handled in your \`handle\` hook):`
+			'\nWarning: vercel.json defines cron tasks that use paths that do not correspond to an API route with a GET handler (ignore this if the request is handled in your `handle` hook):'
 		);
 
 		for (const path of unmatched_paths) {

packages/create-svelte/bin.js

@@ -114,7 +114,7 @@ await create(cwd, {
 	vitest: options.features.includes('vitest')
 });
 
-p.outro(`Your project is ready!`);
+p.outro('Your project is ready!');
 
 if (options.types === 'typescript') {
 	console.log(bold('✔ Typescript'));

packages/create-svelte/scripts/build-templates.js

@@ -39,7 +39,7 @@ function strip_jsdoc(content) {
 					return '';
 				}
 
-				return `/**${description.replace(/\*\ $/, '')}*/${whitespace}`;
+				return `/**${description.replace(/\* $/, '')}*/${whitespace}`;
 			}
 		);
 }

packages/create-svelte/test/check.js

@@ -32,7 +32,7 @@ for (const pkg_path of glob(resolve_path('../../../packages/*/package.json'))) {
 
 try {
 	const kit_dir = resolve_path('../../../packages/kit');
-	const ls_vite_result = execSync(`pnpm ls --json vite`, { cwd: kit_dir });
+	const ls_vite_result = execSync('pnpm ls --json vite', { cwd: kit_dir });
 	const vite_version = JSON.parse(ls_vite_result.toString())[0].devDependencies.vite.version;
 	overrides.vite = vite_version;
 } catch (e) {
@@ -61,7 +61,7 @@ fs.writeFileSync(path.join(test_workspace_dir, 'pnpm-workspace.yaml'), 'packages
 const exec_async = promisify(exec);
 
 beforeAll(async () => {
-	await exec_async(`pnpm install --no-frozen-lockfile`, {
+	await exec_async('pnpm install --no-frozen-lockfile', {
 		cwd: test_workspace_dir
 	});
 }, 60000);

packages/kit/src/core/config/options.js

@@ -210,7 +210,7 @@ const options = object(
 					(/** @type {any} */ { message }) => {
 						throw new Error(
 							message +
-								`\nTo suppress or handle this error, implement \`handleHttpError\` in https://kit.svelte.dev/docs/configuration#prerender`
+								'\nTo suppress or handle this error, implement `handleHttpError` in https://kit.svelte.dev/docs/configuration#prerender'
 						);
 					},
 					(input, keypath) => {
@@ -224,7 +224,7 @@ const options = object(
 					(/** @type {any} */ { message }) => {
 						throw new Error(
 							message +
-								`\nTo suppress or handle this error, implement \`handleMissingId\` in https://kit.svelte.dev/docs/configuration#prerender`
+								'\nTo suppress or handle this error, implement `handleMissingId` in https://kit.svelte.dev/docs/configuration#prerender'
 						);
 					},
 					(input, keypath) => {
@@ -238,7 +238,7 @@ const options = object(
 					(/** @type {any} */ { message }) => {
 						throw new Error(
 							message +
-								`\nTo suppress or handle this error, implement \`handleEntryGeneratorMismatch\` in https://kit.svelte.dev/docs/configuration#prerender`
+								'\nTo suppress or handle this error, implement `handleEntryGeneratorMismatch` in https://kit.svelte.dev/docs/configuration#prerender'
 						);
 					},
 					(input, keypath) => {

packages/kit/src/core/env.js

@@ -75,7 +75,7 @@ export function create_dynamic_types(id, env, prefix) {
 
 	if (id === 'private') {
 		properties.push(`${prefixed}: undefined;`);
-		properties.push(`[key: string]: string | undefined;`);
+		properties.push('[key: string]: string | undefined;');
 	} else {
 		properties.push(`${prefixed}: string | undefined;`);
 	}

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

@@ -55,7 +55,7 @@ export function generate_manifest({ build_data, relative_path, routes }) {
 
 	/** @param {Array<number | undefined>} indexes */
 	function get_nodes(indexes) {
-		let string = indexes.map((n) => reindexed.get(n) ?? '').join(',');
+		const string = indexes.map((n) => reindexed.get(n) ?? '').join(',');
 
 		// since JavaScript ignores trailing commas, we need to insert a dummy
 		// comma so that the array has the correct length if the last item

packages/kit/src/core/sync/create_manifest_data/index.js

@@ -456,7 +456,7 @@ function analyze(project_relative, file, component_extensions, module_extensions
 			);
 		}
 
-		const kind = !!(match[1] || match[4] || match[7]) ? 'server' : 'universal';
+		const kind = match[1] || match[4] || match[7] ? 'server' : 'universal';
 
 		return {
 			kind,
@@ -513,7 +513,7 @@ function prevent_conflicts(routes) {
 		const normalized = normalize_route_id(route.id);
 
 		// find all permutations created by optional parameters
-		const split = normalized.split(/<\?(.+?)\>/g);
+		const split = normalized.split(/<\?(.+?)>/g);
 
 		let permutations = [/** @type {string} */ (split[0])];
 

packages/kit/src/core/sync/write_client_manifest.js

@@ -21,7 +21,7 @@ export function write_client_manifest(kit, manifest_data, output, metadata) {
 		if (node.universal) {
 			declarations.push(
 				`import * as universal from ${s(relative_path(`${output}/nodes`, node.universal))};`,
-				`export { universal };`
+				'export { universal };'
 			);
 		}
 

packages/kit/src/core/sync/write_server.js

@@ -75,7 +75,7 @@ export { set_assets, set_building, set_private_env, set_public_env };
  * @param {string} output
  */
 export function write_server(config, output) {
-	// TODO the casting shouldn't be necessary — investigate
+	// TODO the casting shouldn't be necessary — investigate
 	const hooks_file = /** @type {string} */ (resolve_entry(config.kit.files.hooks.server));
 
 	/** @param {string} file */

packages/kit/src/core/sync/write_types/index.js

@@ -52,7 +52,7 @@ export async function write_all_types(config, manifest_data) {
 	// it could be invoked by another process in the meantime.
 	const meta_data_file = `${types_dir}/route_meta_data.json`;
 	const has_meta_data = fs.existsSync(meta_data_file);
-	let meta_data = has_meta_data
+	const meta_data = has_meta_data
 		? /** @type {Record<string, string[]>} */ (JSON.parse(fs.readFileSync(meta_data_file, 'utf-8')))
 		: {};
 	const routes_map = create_routes_map(manifest_data);
@@ -177,7 +177,7 @@ function update_types(config, routes, route, to_delete = new Set()) {
 	const outdir = path.join(config.kit.outDir, 'types', routes_dir, route.id);
 
 	// now generate new types
-	const imports = [`import type * as Kit from '@sveltejs/kit';`];
+	const imports = ["import type * as Kit from '@sveltejs/kit';"];
 
 	/** @type {string[]} */
 	const declarations = [];
@@ -196,7 +196,7 @@ function update_types(config, routes, route, to_delete = new Set()) {
 
 	if (route.params.length > 0) {
 		exports.push(
-			`export type EntryGenerator = () => Promise<Array<RouteParams>> | Array<RouteParams>;`
+			'export type EntryGenerator = () => Promise<Array<RouteParams>> | Array<RouteParams>;'
 		);
 	}
 
@@ -206,24 +206,24 @@ function update_types(config, routes, route, to_delete = new Set()) {
 	if (route.layout || route.leaf) {
 		declarations.push(
 			// If T extends the empty object, void is also allowed as a return type
-			`type MaybeWithVoid<T> = {} extends T ? T | void : T;`,
+			'type MaybeWithVoid<T> = {} extends T ? T | void : T;',
 
 			// Returns the key of the object whose values are required.
-			`export type RequiredKeys<T> = { [K in keyof T]-?: {} extends { [P in K]: T[K] } ? never : K; }[keyof T];`,
+			'export type RequiredKeys<T> = { [K in keyof T]-?: {} extends { [P in K]: T[K] } ? never : K; }[keyof T];',
 
 			// Helper type to get the correct output type for load functions. It should be passed the parent type to check what types from App.PageData are still required.
 			// If none, void is also allowed as a return type.
-			`type OutputDataShape<T> = MaybeWithVoid<Omit<App.PageData, RequiredKeys<T>> & Partial<Pick<App.PageData, keyof T & keyof App.PageData>> & Record<string, any>>`,
+			'type OutputDataShape<T> = MaybeWithVoid<Omit<App.PageData, RequiredKeys<T>> & Partial<Pick<App.PageData, keyof T & keyof App.PageData>> & Record<string, any>>',
 
 			// null & {} == null, we need to prevent that in some situations
-			`type EnsureDefined<T> = T extends null | undefined ? {} : T;`,
+			'type EnsureDefined<T> = T extends null | undefined ? {} : T;',
 
 			// Takes a union type and returns a union type where each type also has all properties
 			// of all possible types (typed as undefined), making accessing them more ergonomic
-			`type OptionalUnion<U extends Record<string, any>, A extends keyof U = U extends U ? keyof U : never> = U extends unknown ? { [P in Exclude<A, keyof U>]?: never } & U : never;`,
+			'type OptionalUnion<U extends Record<string, any>, A extends keyof U = U extends U ? keyof U : never> = U extends unknown ? { [P in Exclude<A, keyof U>]?: never } & U : never;',
 
 			// Re-export `Snapshot` from @sveltejs/kit — in future we could use this to infer <T> from the return type of `snapshot.capture`
-			`export type Snapshot<T = any> = Kit.Snapshot<T>;`
+			'export type Snapshot<T = any> = Kit.Snapshot<T>;'
 		);
 	}
 
@@ -255,10 +255,10 @@ function update_types(config, routes, route, to_delete = new Set()) {
 
 		if (route.leaf.server) {
 			exports.push(
-				`export type Action<OutputData extends Record<string, any> | void = Record<string, any> | void> = Kit.Action<RouteParams, OutputData, RouteId>`
+				'export type Action<OutputData extends Record<string, any> | void = Record<string, any> | void> = Kit.Action<RouteParams, OutputData, RouteId>'
 			);
 			exports.push(
-				`export type Actions<OutputData extends Record<string, any> | void = Record<string, any> | void> = Kit.Actions<RouteParams, OutputData, RouteId>`
+				'export type Actions<OutputData extends Record<string, any> | void = Record<string, any> | void> = Kit.Actions<RouteParams, OutputData, RouteId>'
 			);
 		}
 	}
@@ -326,11 +326,11 @@ function update_types(config, routes, route, to_delete = new Set()) {
 	}
 
 	if (route.endpoint) {
-		exports.push(`export type RequestHandler = Kit.RequestHandler<RouteParams, RouteId>;`);
+		exports.push('export type RequestHandler = Kit.RequestHandler<RouteParams, RouteId>;');
 	}
 
 	if (route.leaf?.server || route.layout?.server || route.endpoint) {
-		exports.push(`export type RequestEvent = Kit.RequestEvent<RouteParams, RouteId>;`);
+		exports.push('export type RequestEvent = Kit.RequestEvent<RouteParams, RouteId>;');
 	}
 
 	const output = [imports.join('\n'), declarations.join('\n'), exports.join('\n')]
@@ -386,7 +386,7 @@ function process_node(node, outdir, is_page, proxies, all_pages_have_load = true
 		// +page.js load present -> server can return all-optional data
 		const output_data_shape =
 			node.universal || (!is_page && all_pages_have_load)
-				? `Partial<App.PageData> & Record<string, any> | void`
+				? 'Partial<App.PageData> & Record<string, any> | void'
 				: `OutputDataShape<${parent_type}>`;
 		exports.push(
 			`export type ${prefix}ServerLoad<OutputData extends ${output_data_shape} = ${output_data_shape}> = Kit.ServerLoad<${params}, ${parent_type}, OutputData, ${route_id}>;`
@@ -404,15 +404,15 @@ function process_node(node, outdir, is_page, proxies, all_pages_have_load = true
 					: path_to_original(outdir, node.server);
 
 				exports.push(
-					`type ExcludeActionFailure<T> = T extends Kit.ActionFailure<any> ? never : T extends void ? never : T;`,
-					`type ActionsSuccess<T extends Record<string, (...args: any) => any>> = { [Key in keyof T]: ExcludeActionFailure<Awaited<ReturnType<T[Key]>>>; }[keyof T];`,
-					`type ExtractActionFailure<T> = T extends Kit.ActionFailure<infer X>	? X extends void ? never : X : never;`,
-					`type ActionsFailure<T extends Record<string, (...args: any) => any>> = { [Key in keyof T]: Exclude<ExtractActionFailure<Awaited<ReturnType<T[Key]>>>, void>; }[keyof T];`,
+					'type ExcludeActionFailure<T> = T extends Kit.ActionFailure<any> ? never : T extends void ? never : T;',
+					'type ActionsSuccess<T extends Record<string, (...args: any) => any>> = { [Key in keyof T]: ExcludeActionFailure<Awaited<ReturnType<T[Key]>>>; }[keyof T];',
+					'type ExtractActionFailure<T> = T extends Kit.ActionFailure<infer X>	? X extends void ? never : X : never;',
+					'type ActionsFailure<T extends Record<string, (...args: any) => any>> = { [Key in keyof T]: Exclude<ExtractActionFailure<Awaited<ReturnType<T[Key]>>>, void>; }[keyof T];',
 					`type ActionsExport = typeof import('${from}').actions`,
-					`export type SubmitFunction = Kit.SubmitFunction<Expand<ActionsSuccess<ActionsExport>>, Expand<ActionsFailure<ActionsExport>>>`
+					'export type SubmitFunction = Kit.SubmitFunction<Expand<ActionsSuccess<ActionsExport>>, Expand<ActionsFailure<ActionsExport>>>'
 				);
 
-				type = `Expand<Kit.AwaitedActions<ActionsExport>> | null`;
+				type = 'Expand<Kit.AwaitedActions<ActionsExport>> | null';
 			}
 			exports.push(`export type ActionData = ${type};`);
 		}
@@ -440,7 +440,7 @@ function process_node(node, outdir, is_page, proxies, all_pages_have_load = true
 
 		const output_data_shape =
 			!is_page && all_pages_have_load
-				? `Partial<App.PageData> & Record<string, any> | void`
+				? 'Partial<App.PageData> & Record<string, any> | void'
 				: `OutputDataShape<${parent_type}>`;
 		exports.push(
 			`export type ${prefix}Load<OutputData extends ${output_data_shape} = ${output_data_shape}> = Kit.Load<${params}, ${prefix}ServerData, ${parent_type}, OutputData, ${route_id}>;`
@@ -688,7 +688,7 @@ export function tweak_types(content, is_server) {
 						// remove type from `export const load: Load ...`
 						if (declaration.type) {
 							let a = declaration.type.pos;
-							let b = declaration.type.end;
+							const b = declaration.type.end;
 							while (/\s/.test(content[a])) a += 1;
 
 							const type = content.slice(a, b);
@@ -760,7 +760,7 @@ export function tweak_types(content, is_server) {
 						// remove type from `export const actions: Actions ...`
 						if (declaration.type) {
 							let a = declaration.type.pos;
-							let b = declaration.type.end;
+							const b = declaration.type.end;
 							while (/\s/.test(content[a])) a += 1;
 
 							const type = content.slice(a, b);
@@ -788,7 +788,7 @@ export function tweak_types(content, is_server) {
 											if (arg && !arg.type) {
 												code.appendLeft(
 													arg.name.end,
-													`: import('./$types').RequestEvent` + (add_parens ? ')' : '')
+													": import('./$types').RequestEvent" + (add_parens ? ')' : '')
 												);
 											}
 										}