feat(scripts): improve typechecking performance

Explicitly add some options in project config so that it can be
improved from userland.

See #447

Author: swashata

examples/plugin/src/ts/main.ts

@@ -7,6 +7,8 @@ console.log('Hello from typescript, I am gonna say foo 30 times');
 console.log(strRepeat('foo', 10));
 console.log(strRepeat('foo', 10));
 console.log(strRepeat('foo', 10));
+console.log(strRepeat('10', 20));
+console.log(strRepeat('[]', 20));
 
 if (module.hot) {
 	module.hot.accept('./module.ts', () => {

examples/plugin/wpackio.project.js

@@ -35,6 +35,7 @@ module.exports = {
 				main: ['./src/app/index.js'],
 				mobile: ['./src/app/mobile.js'],
 			},
+			hasTypeScript: false,
 			// Extra webpack config to be passed directly
 			webpackConfig: (config, merge, appDir, isDev) => {
 				const svgoLoader = {
@@ -98,6 +99,7 @@ module.exports = {
 			entry: {
 				main: ['./src/foo/foo.js'],
 			},
+			hasTypeScript: false,
 			// Extra webpack config to be passed directly
 			webpackConfig: undefined,
 		},
@@ -108,6 +110,7 @@ module.exports = {
 			entry: {
 				main: ['./src/reactapp/index.jsx'],
 			},
+			hasTypeScript: false,
 			webpackConfig: (config, merge, appDir, isDev) => {
 				const customRules = {
 					module: {
@@ -168,6 +171,8 @@ module.exports = {
 		},
 		{
 			name: 'tsapp',
+			// hasTypeScript: true,
+			typeWatchFiles: ['src/ts/*.{ts,tsx}', 'src/ts/**/*.{ts,tsx}'],
 			entry: {
 				main: ['./src/ts/main.ts'],
 			},

packages/scripts/src/bin/utils.ts

@@ -71,6 +71,10 @@ export function printFailedCompileMEssage() {
 	);
 }
 
+export function printGeneralInfoMessage(msg: string) {
+	console.info(addTimeStampToLog(`${logSymbols.info} ${msg}`));
+}
+
 export const bulletSymbol = chalk.magenta(figures.pointer);
 
 export const wpackLogoSmall = gradient.instagram('wpack.io');

packages/scripts/src/config/WebpackConfigHelper.ts

@@ -22,6 +22,7 @@ import {
 } from './project.config.default';
 import { ServerConfig } from './server.config.default';
 import { getFileLoaderForJsAndStyleAssets } from './fileLoader';
+import { printGeneralInfoMessage } from '../bin/utils';
 
 interface NormalizedEntry {
 	[x: string]: string[];
@@ -282,7 +283,10 @@ export class WebpackConfigHelper {
 		];
 		// Add ts checker plugin if project has tsconfig.json
 		const tsconfigPath = path.resolve(this.cwd, './tsconfig.json');
-		if (this.fileExists(tsconfigPath)) {
+		if (
+			this.fileExists(tsconfigPath) &&
+			this.file.hasTypeScript !== false
+		) {
 			// dynamic require forktschecker otherwise it will throw error
 			try {
 				// eslint-disable-next-line import/no-extraneous-dependencies, global-require, @typescript-eslint/no-var-requires
@@ -297,6 +301,10 @@ export class WebpackConfigHelper {
 						formatterOptions: {
 							highlightCode: true,
 						},
+						useTypescriptIncrementalApi: false,
+						reportFiles: this.file.typeWatchFiles
+							? this.file.typeWatchFiles
+							: [],
 					})
 				);
 			} catch (e) {

packages/scripts/src/config/project.config.default.ts

@@ -31,6 +31,8 @@ export interface EntryConfig {
 export interface FileConfig {
 	name: string;
 	entry: EntryConfig;
+	typeWatchFiles?: string[];
+	hasTypeScript?: boolean;
 	webpackConfig?:
 		| webpack.Configuration
 		| ((

site/docs/apis/project-configuration.md

@@ -184,15 +184,37 @@ under `entry`, then also (if needed) chunk-splitting will be applied.
 If we were to pass multiple file object, then webpack would run in [multi-compiler](https://webpack.js.org/api/node/#multicompiler)
 mode, separating dependency tree from each of the file object.
 
-Each file object has three properties:
+Each file object has two required and three optional properties. Here's the
+interface.
 
-#### `name` (`string`):
+```ts
+interface EntryConfig {
+	[x: string]: string[] | string;
+}
+
+interface FileConfig {
+	name: string;
+	entry: EntryConfig;
+	typeWatchFiles?: string[];
+	hasTypeScript?: boolean;
+	webpackConfig?:
+		| webpack.Configuration
+		| ((
+				config: webpack.Configuration,
+				api: merge,
+				appDir: string,
+				isDev: boolean
+		  ) => webpack.Configuration);
+}
+```
+
+#### `name` (`string`) **required**:
 
 A unique name of this file entry. If you are using more than one file entry,
 then make sure to give different names, otherwise the compiler might not work
 in development mode.
 
-#### `entry` (`object`):
+#### `entry` (`object`) **required**:
 
 This is the path (relative to project root) of files you would like to compile.
 
@@ -245,6 +267,16 @@ Directory inside `outputPath` where all the assets are to be emitted.
 
 Whether the operation is going for development mode or production build.
 
+#### `typeWatchFiles` (`string[]`)
+
+Array of glob pattern for which typescript reports are to be notified.
+
+#### `hasTypeScript` (`boolean` | `undefined`)
+
+Explicitly disable typescript type assertions.
+
+> More information about typescript related options can be found [here](/tutorials/adding-typescript/).
+
 ## `outputPath` (`string`):
 
 Name of the directory (relative) where we would put the bundled and manifest

site/docs/tutorials/adding-typescript.md

@@ -83,3 +83,55 @@ Now you are good to go. The compiler will also show any `ts` error you might hav
 > **NOTE** - Internally wpack.io depends on [`fork-ts-checker-webpack-plugin`](https://github.com/Realytics/fork-ts-checker-webpack-plugin)
 > to show type errors during build time. So make sure you install it, otherwise
 > it will not work.
+
+## Optimization
+
+By default `@wpackio/scripts` will create an instance of `fork-ts-checker-webpack-plugin`
+if a `tsconfig.json` is found in the current project root.
+
+The same plugin would go into all multi-entry compiler instances and would enable
+typechecking for all entries.
+
+Sometimes, this could not be the desired feature. For instance, you might have
+a plain JS app, alongside a TS app and you don't want the typechecker for the JS
+app. Luckily it is not possible to explicitly disable typechecking for individual
+file entry using `hasTypeScript`.
+
+Furthermore, due to the nature of TypeScript, you might notice duplicate error
+reports across multiple files entry. This can also be remedied using `typeWatchFiles`
+config variable.
+
+Under your [`FileConfig`](/apis/project-configuration/#files-array) add the
+`hasTypeScript` option. Below is an example of two apps, one explicitly disabling
+the typecheck.
+
+**wpackio.project.js**
+
+```js
+module.exports = {
+	// ...
+	files: [
+		// Only JavaScript App
+		{
+			name: 'jsapp',
+			entry: {
+				main: './src/jsapp/index.js',
+			},
+			// disable typechecking for this
+			hasTypeScript: false,
+		},
+		// TypeScript App
+		{
+			name: 'tsapp',
+			entry: {
+				main: './src/tsapp/index.ts',
+			},
+			// (optional) enable typechecking for this
+			hasTypeScript: true,
+			// (optional but recommended) mention files to report
+			// through glob pattern
+			typeWatchFiles: ['src/tsapp/*.{ts,tsx}', 'src/tsapp/**/*.{ts,tsx}'],
+		},
+	],
+};
+```