feat(plugin-vite): hot-restart 🔥

packages/plugin/vite/src/Config.ts

@@ -9,6 +9,11 @@ export interface VitePluginBuildConfig {
    * Vite config file path.
    */
   config?: string;
+  /**
+   * By default, when any entry in `build` is rebuilt it will restart the Electron App.
+   * If you want to customize this behavior, you can pass a function and control it with the `args.restart` provided by the function.
+   */
+  restart?: false | ((args: { restart: () => void }) => void | Promise<void>);
 }
 
 export interface VitePluginRendererConfig {

packages/plugin/vite/src/ViteConfig.ts

@@ -4,7 +4,7 @@ import debug from 'debug';
 import { ConfigEnv, loadConfigFromFile, mergeConfig, UserConfig } from 'vite';
 
 import { VitePluginConfig } from './Config';
-import { externalBuiltins } from './util/plugins';
+import { externalBuiltins, hotRestart } from './util/plugins';
 
 const d = debug('electron-forge:plugin:vite:viteconfig');
 
@@ -68,7 +68,7 @@ export default class ViteConfigGenerator {
     const plugins = [externalBuiltins()];
     const configs = this.pluginConfig.build
       .filter(({ entry, config }) => entry || config)
-      .map<Promise<UserConfig>>(async ({ entry, config }) => {
+      .map<Promise<UserConfig>>(async ({ entry, config, restart }) => {
         const defaultConfig: UserConfig = {
           // Ensure that each build config loads the .env file correctly.
           mode: this.mode,
@@ -89,7 +89,7 @@ export default class ViteConfigGenerator {
           },
           clearScreen: false,
           define,
-          plugins,
+          plugins: [...plugins, hotRestart(restart)],
         };
         if (config) {
           const loadResult = await this.resolveConfig(config);

packages/plugin/vite/src/util/plugins.ts

@@ -1,6 +1,8 @@
 import { builtinModules } from 'node:module';
 
-import type { Plugin } from 'vite';
+import { VitePluginBuildConfig } from '../Config';
+
+import type { Plugin, ResolvedConfig } from 'vite';
 
 /**
  * `electron` and Node.js built-in modules should always be externalize.
@@ -33,3 +35,42 @@ export function externalBuiltins() {
     },
   };
 }
+
+/**
+ * Hot restart App during development for DX.
+ */
+export function hotRestart(options: VitePluginBuildConfig['restart']) {
+  let config: ResolvedConfig;
+  const restart = () => {
+    // https://github.com/electron/forge/blob/v6.0.5/packages/api/core/src/api/start.ts#L204-L211
+    process.stdin.emit('data', 'rs');
+  };
+  // Avoid first start, it's stated by forge.
+  let isFirstStart = false;
+
+  return <Plugin>{
+    name: '@electron-forge/plugin-vite:hot-restart',
+    configResolved(_config) {
+      config = _config;
+    },
+    closeBundle() {
+      if (config.mode === 'production') {
+        // https://github.com/electron/forge/blob/v6.1.1/packages/plugin/vite/src/ViteConfig.ts#L36-L41
+        return;
+      }
+      if (options === false) {
+        return;
+      }
+      if (!isFirstStart) {
+        isFirstStart = true;
+        return;
+      }
+      if (typeof options === 'function') {
+        // Leave it to the user to decide whether to restart.
+        options({ restart });
+      } else {
+        restart();
+      }
+    },
+  };
+}

packages/plugin/vite/test/ViteConfig_spec.ts

@@ -42,7 +42,7 @@ describe('ViteConfigGenerator', () => {
       clearScreen: false,
       define: {},
       // shims
-      plugins: [buildConfig.plugins?.[0]],
+      plugins: buildConfig.plugins,
     } as UserConfig);
   });