refactor(core): migrate utils to TS

lib/core/package.json

@@ -134,6 +134,8 @@
     "webpack-virtual-modules": "^0.2.2"
   },
   "devDependencies": {
+    "@types/mock-fs": "^4.10.0",
+    "@types/interpret": "^1.1.1",
     "mock-fs": "^4.12.0"
   },
   "peerDependencies": {

lib/core/src/server/utils/interpret-files.ts

@@ -14,13 +14,13 @@ function sortExtensions() {
 
 const possibleExtensions = sortExtensions();
 
-export function getInterpretedFile(pathToFile) {
+export function getInterpretedFile(pathToFile: string) {
   return possibleExtensions
     .map((ext) => (pathToFile.endsWith(ext) ? pathToFile : `${pathToFile}${ext}`))
     .find((candidate) => fs.existsSync(candidate));
 }
 
-export function getInterpretedFileWithExt(pathToFile) {
+export function getInterpretedFileWithExt(pathToFile: string) {
   return possibleExtensions
     .map((ext) => ({ path: pathToFile.endsWith(ext) ? pathToFile : `${pathToFile}${ext}`, ext }))
     .find((candidate) => fs.existsSync(candidate.path));

lib/core/src/server/utils/load-custom-babel-config.ts

@@ -4,7 +4,7 @@ import JSON5 from 'json5';
 
 import { logger } from '@storybook/node-logger';
 
-function removeReactHmre(presets) {
+function removeReactHmre(presets: string[]) {
   const index = presets.indexOf('react-hmre');
   if (index > -1) {
     presets.splice(index, 1);
@@ -12,9 +12,12 @@ function removeReactHmre(presets) {
 }
 
 // Tries to load a .babelrc and returns the parsed object if successful
-function loadFromPath(babelConfigPath) {
+function loadFromPath(babelConfigPath: string) {
   let config;
-  const error = {};
+  const error: {
+    js?: any;
+    json?: any;
+  } = {};
 
   if (fs.existsSync(babelConfigPath)) {
     const content = fs.readFileSync(babelConfigPath, 'utf-8');
@@ -65,7 +68,7 @@ function loadFromPath(babelConfigPath) {
   return config;
 }
 
-export default async function (configDir, getDefaultConfig) {
+export default async function (configDir: string, getDefaultConfig: () => unknown) {
   // Between versions 5.1.0 - 5.1.9 this loaded babel.config.js from the project
   // root, which was an unintentional breaking change. We can add back project support
   // in 6.0.

lib/core/src/server/utils/load-custom-webpack-config.ts

@@ -3,5 +3,5 @@ import { serverRequire } from './server-require';
 
 const webpackConfigs = ['webpack.config', 'webpackfile'];
 
-export default (configDir) =>
+export default (configDir: string) =>
   serverRequire(webpackConfigs.map((configName) => path.resolve(configDir, configName)));

lib/core/src/server/utils/load-manager-or-addons-file.ts

@@ -4,9 +4,7 @@ import dedent from 'ts-dedent';
 
 import { getInterpretedFile } from './interpret-files';
 
-const toArray = (a) => (a ? [a] : a);
-
-export function loadManagerOrAddonsFile({ configDir }) {
+export function loadManagerOrAddonsFile({ configDir }: { configDir: string }) {
   const storybookCustomAddonsPath = getInterpretedFile(path.resolve(configDir, 'addons'));
   const storybookCustomManagerPath = getInterpretedFile(path.resolve(configDir, 'manager'));
 

lib/core/src/server/utils/load-preview-or-config-file.ts

@@ -3,7 +3,7 @@ import dedent from 'ts-dedent';
 
 import { getInterpretedFile } from './interpret-files';
 
-export function loadPreviewOrConfigFile({ configDir }) {
+export function loadPreviewOrConfigFile({ configDir }: { configDir: string }) {
   const storybookConfigPath = getInterpretedFile(path.resolve(configDir, 'config'));
   const storybookPreviewPath = getInterpretedFile(path.resolve(configDir, 'preview'));
 

lib/core/src/server/utils/merge-webpack-config.ts

@@ -1,23 +1,38 @@
-function plugins({ plugins: defaultPlugins = [] }, { plugins: customPlugins = [] }) {
+function plugins<T>(
+  { plugins: defaultPlugins = [] }: { plugins?: T[] },
+  { plugins: customPlugins = [] }: { plugins?: T[] }
+): T[] {
   return [...defaultPlugins, ...customPlugins];
 }
 
-function rules({ rules: defaultRules = [] }, { rules: customRules = [] }) {
+function rules<T>(
+  { rules: defaultRules = [] }: { rules?: T[] },
+  { rules: customRules = [] }: { rules?: T[] }
+): T[] {
   return [...defaultRules, ...customRules];
 }
 
-function extensions({ extensions: defaultExtensions = [] }, { extensions: customExtensions = [] }) {
+function extensions<T>(
+  { extensions: defaultExtensions = [] }: { extensions?: T[] },
+  { extensions: customExtensions = [] }: { extensions?: T[] }
+): T[] {
   return [...defaultExtensions, ...customExtensions];
 }
 
-function alias({ alias: defaultAlias = {} }, { alias: customAlias = {} }) {
+function alias(
+  { alias: defaultAlias = {} }: { alias?: any },
+  { alias: customAlias = {} }: { alias?: any }
+) {
   return {
     ...defaultAlias,
     ...customAlias,
   };
 }
 
-function module({ module: defaultModule = {} }, { module: customModule = {} }) {
+function module(
+  { module: defaultModule = {} }: { module?: any },
+  { module: customModule = {} }: { module?: any }
+) {
   return {
     ...defaultModule,
     ...customModule,
@@ -25,7 +40,10 @@ function module({ module: defaultModule = {} }, { module: customModule = {} }) {
   };
 }
 
-function resolve({ resolve: defaultResolve = {} }, { resolve: customResolve = {} }) {
+function resolve(
+  { resolve: defaultResolve = {} }: { resolve?: any },
+  { resolve: customResolve = {} }: { resolve?: any }
+) {
   return {
     ...defaultResolve,
     ...customResolve,
@@ -35,8 +53,8 @@ function resolve({ resolve: defaultResolve = {} }, { resolve: customResolve = {}
 }
 
 function optimization(
-  { optimization: defaultOptimization = {} },
-  { optimization: customOptimization = {} }
+  { optimization: defaultOptimization = {} }: { optimization?: any },
+  { optimization: customOptimization = {} }: { optimization?: any }
 ) {
   return {
     ...defaultOptimization,
@@ -44,7 +62,7 @@ function optimization(
   };
 }
 
-function mergeConfigs(config, customConfig) {
+function mergeConfigs(config: any, customConfig: any) {
   return {
     // We'll always load our configurations after the custom config.
     // So, we'll always load the stuff we need.

lib/core/src/server/utils/middleware.ts

@@ -1,7 +1,7 @@
 import path from 'path';
 import fs from 'fs';
 
-export function getMiddleware(configDir) {
+export function getMiddleware(configDir: string) {
   const middlewarePath = path.resolve(configDir, 'middleware.js');
   if (fs.existsSync(middlewarePath)) {
     let middlewareModule = require(middlewarePath); // eslint-disable-line

lib/core/src/server/utils/prebuilt-manager.ts

@@ -17,7 +17,13 @@ export const IGNORED_ADDONS = [
   ...DEFAULT_ADDONS,
 ];
 
-export const getPrebuiltDir = async ({ configDir, options }) => {
+export const getPrebuiltDir = async ({
+  configDir,
+  options,
+}: {
+  configDir: string;
+  options: { managerCache?: boolean };
+}) => {
   if (options.managerCache === false) return false;
 
   const prebuiltDir = path.join(__dirname, '../../../prebuilt');
@@ -33,7 +39,7 @@ export const getPrebuiltDir = async ({ configDir, options }) => {
   const { addons, refs, managerBabel, managerWebpack } = serverRequire(mainConfigFile);
   if (!addons || refs || managerBabel || managerWebpack) return false;
   if (DEFAULT_ADDONS.some((addon) => !addons.includes(addon))) return false;
-  if (addons.some((addon) => !IGNORED_ADDONS.includes(addon))) return false;
+  if (addons.some((addon: string) => !IGNORED_ADDONS.includes(addon))) return false;
 
   // Auto refs will not be listed in the config, so we have to verify there aren't any
   const autoRefs = await getAutoRefs({ configDir });

lib/core/src/server/utils/resolve-path-in-sb-cache.ts

@@ -9,7 +9,7 @@ import pkgDir from 'pkg-dir';
  * @param fileOrDirectoryName {string} Name of the file or directory
  * @return {string} Absolute path to the file or directory
  */
-export function resolvePathInStorybookCache(fileOrDirectoryName) {
+export function resolvePathInStorybookCache(fileOrDirectoryName: string) {
   const cwd = process.cwd();
   const projectDir = pkgDir.sync(cwd);
 

lib/core/src/server/utils/server-require.ts

@@ -7,7 +7,7 @@ import { getInterpretedFileWithExt } from './interpret-files';
 
 const compilersState = new Map();
 
-function registerCompiler(moduleDescriptor) {
+function registerCompiler(moduleDescriptor: any): number {
   if (!moduleDescriptor) {
     return 0;
   }
@@ -47,7 +47,7 @@ function registerCompiler(moduleDescriptor) {
   return registered;
 }
 
-function interopRequireDefault(filePath) {
+function interopRequireDefault(filePath: string) {
   // eslint-disable-next-line import/no-dynamic-require,global-require
   const result = require(filePath);
 
@@ -57,7 +57,7 @@ function interopRequireDefault(filePath) {
   return isES6DefaultExported ? result.default : result;
 }
 
-function getCandidate(paths) {
+function getCandidate(paths: string[]) {
   for (let i = 0; i < paths.length; i += 1) {
     const candidate = getInterpretedFileWithExt(paths[i]);
 
@@ -69,7 +69,7 @@ function getCandidate(paths) {
   return undefined;
 }
 
-export function serverRequire(filePath) {
+export function serverRequire(filePath: string | string[]) {
   const candidatePath = serverResolve(filePath);
 
   if (!candidatePath) {
@@ -90,7 +90,7 @@ export function serverRequire(filePath) {
   return interopRequireDefault(candidatePath);
 }
 
-export function serverResolve(filePath) {
+export function serverResolve(filePath: string | string[]) {
   const paths = Array.isArray(filePath) ? filePath : [filePath];
   const existingCandidate = getCandidate(paths);
 

lib/core/src/server/utils/template.ts

@@ -1,10 +1,10 @@
 import path from 'path';
 import fs from 'fs';
 
-const interpolate = (string, data = {}) =>
+const interpolate = (string: string, data: Record<string, string> = {}) =>
   Object.entries(data).reduce((acc, [k, v]) => acc.replace(new RegExp(`%${k}%`, 'g'), v), string);
 
-export function getPreviewBodyHtml(configDirPath, interpolations) {
+export function getPreviewBodyHtml(configDirPath: string, interpolations?: Record<string, string>) {
   const base = fs.readFileSync(
     path.resolve(__dirname, '../templates/base-preview-body.html'),
     'utf8'
@@ -20,7 +20,7 @@ export function getPreviewBodyHtml(configDirPath, interpolations) {
   return interpolate(result, interpolations);
 }
 
-export function getPreviewHeadHtml(configDirPath, interpolations) {
+export function getPreviewHeadHtml(configDirPath: string, interpolations?: Record<string, string>) {
   const base = fs.readFileSync(
     path.resolve(__dirname, '../templates/base-preview-head.html'),
     'utf8'
@@ -36,7 +36,7 @@ export function getPreviewHeadHtml(configDirPath, interpolations) {
   return interpolate(result, interpolations);
 }
 
-export function getManagerHeadHtml(configDirPath, interpolations) {
+export function getManagerHeadHtml(configDirPath: string, interpolations: Record<string, string>) {
   const base = fs.readFileSync(
     path.resolve(__dirname, '../templates/base-manager-head.html'),
     'utf8'

lib/core/src/server/utils/validate-configuration-files.ts

@@ -13,7 +13,7 @@ const warnLegacyConfigurationFiles = deprecate(
   `
 );
 
-const errorMixingConfigFiles = (first, second, configDir) => {
+const errorMixingConfigFiles = (first: string, second: string, configDir: string) => {
   const firstPath = path.resolve(configDir, first);
   const secondPath = path.resolve(configDir, second);
   throw new Error(dedent`
@@ -25,9 +25,9 @@ const errorMixingConfigFiles = (first, second, configDir) => {
   `);
 };
 
-export default function validateConfigurationFiles(configDir) {
+export default function validateConfigurationFiles(configDir: string) {
   const extensionsPattern = `{${Array.from(boost).join(',')}}`;
-  const exists = (file) =>
+  const exists = (file: string) =>
     !!glob.sync(path.resolve(configDir, `${file}${extensionsPattern}`)).length;
 
   const main = exists('main');

yarn.lock

@@ -6113,6 +6113,13 @@
     "@types/through" "*"
     rxjs "^6.4.0"
 
+"@types/interpret@^1.1.1":
+  version "1.1.1"
+  resolved "https://registry.yarnpkg.com/@types/interpret/-/interpret-1.1.1.tgz#b1bf85b0420e2414b989ce237658ad20dc03719b"
+  integrity sha512-HZ4d0m2Ebl8DmrOdYZHgYyipj/8Ftq1/ssB/oQR7fqfUrwtTP7IW3BDi2V445nhPBLzZjEkApaPVp83moSCXlA==
+  dependencies:
+    "@types/node" "*"
+
 "@types/is-function@^1.0.0":
   version "1.0.0"
   resolved "https://registry.yarnpkg.com/@types/is-function/-/is-function-1.0.0.tgz#1b0b819b1636c7baf0d6785d030d12edf70c3e83"
@@ -6238,6 +6245,13 @@
   resolved "https://registry.yarnpkg.com/@types/mithril/-/mithril-2.0.3.tgz#f24a764515d9b17095845838b12f2444757d93fa"
   integrity sha512-cZHOdO2IiXYeyjeDYdbOisSdfaJRzfmRo3zVzgu33IWTMA0KEQObp9fdvqcuYdPz93iJ1yCl19GcEjo/9yv+yA==
 
+"@types/mock-fs@^4.10.0":
+  version "4.10.0"
+  resolved "https://registry.yarnpkg.com/@types/mock-fs/-/mock-fs-4.10.0.tgz#460061b186993d76856f669d5317cda8a007c24b"
+  integrity sha512-FQ5alSzmHMmliqcL36JqIA4Yyn9jyJKvRSGV3mvPh108VFatX7naJDzSG4fnFQNZFq9dIx0Dzoe6ddflMB2Xkg==
+  dependencies:
+    "@types/node" "*"
+
 "@types/node-cleanup@^2.1.1":
   version "2.1.1"
   resolved "https://registry.yarnpkg.com/@types/node-cleanup/-/node-cleanup-2.1.1.tgz#c8f78a648897d2a40ed10632268ce15d343cc191"