chore: Simplify virtual module setup (#581)

scripts/build.ts

@@ -8,6 +8,10 @@ import { consola } from 'consola';
 import pMap from 'p-map';
 import os from 'node:os';
 import path from 'node:path';
+import {
+  virtualModuleNames,
+  virtualEntrypointModuleNames,
+} from '~/core/utils/virtual-modules';
 
 const spinnerText = 'Building WXT';
 const spinner = ora(spinnerText).start();
@@ -20,12 +24,7 @@ const preset = {
   dts: true,
   silent: true,
   sourcemap: false,
-  external: [
-    'virtual:user-unlisted-script',
-    'virtual:user-content-script-isolated-world',
-    'virtual:user-content-script-main-world',
-    'virtual:user-background',
-  ],
+  external: virtualEntrypointModuleNames.map((name) => `virtual:user-${name}`),
 } satisfies tsup.Options;
 
 function spinnerPMap(configs: tsup.Options[]) {
@@ -74,17 +73,13 @@ const config: tsup.Options[] = [
   },
   {
     ...preset,
-    entry: {
-      'virtual/background-entrypoint': 'src/virtual/background-entrypoint.ts',
-      'virtual/content-script-isolated-world-entrypoint':
-        'src/virtual/content-script-isolated-world-entrypoint.ts',
-      'virtual/content-script-main-world-entrypoint':
-        'src/virtual/content-script-main-world-entrypoint.ts',
-      'virtual/mock-browser': 'src/virtual/mock-browser.ts',
-      'virtual/reload-html': 'src/virtual/reload-html.ts',
-      'virtual/unlisted-script-entrypoint':
-        'src/virtual/unlisted-script-entrypoint.ts',
-    },
+    entry: virtualModuleNames.reduce<Record<string, string>>(
+      (acc, moduleName) => {
+        acc[`virtual/${moduleName}`] = `src/virtual/${moduleName}.ts`;
+        return acc;
+      },
+      {},
+    ),
     format: ['esm'],
     splitting: false,
     dts: false,

src/core/builders/vite/index.ts

@@ -3,7 +3,6 @@ import {
   BuildStepOutput,
   Entrypoint,
   ResolvedConfig,
-  VirtualEntrypointType,
   WxtBuilder,
   WxtBuilderServer,
   WxtDevServer,
@@ -13,6 +12,10 @@ import {
   getEntrypointBundlePath,
   isHtmlEntrypoint,
 } from '~/core/utils/entrypoints';
+import {
+  VirtualEntrypointType,
+  VirtualModuleId,
+} from '~/core/utils/virtual-modules';
 
 export async function createViteBuilder(
   wxtConfig: ResolvedConfig,
@@ -48,10 +51,7 @@ export async function createViteBuilder(
       wxtPlugins.download(wxtConfig),
       wxtPlugins.devHtmlPrerender(wxtConfig, server),
       wxtPlugins.unimport(wxtConfig),
-      wxtPlugins.virtualEntrypoint('background', wxtConfig),
-      wxtPlugins.virtualEntrypoint('content-script-isolated-world', wxtConfig),
-      wxtPlugins.virtualEntrypoint('content-script-main-world', wxtConfig),
-      wxtPlugins.virtualEntrypoint('unlisted-script', wxtConfig),
+      wxtPlugins.resolveVirtualModules(wxtConfig),
       wxtPlugins.devServerGlobals(wxtConfig, server),
       wxtPlugins.tsconfigPaths(wxtConfig),
       wxtPlugins.noopBackground(),
@@ -268,7 +268,10 @@ function getRollupEntry(entrypoint: Entrypoint): string {
           : 'content-script-isolated-world';
       break;
   }
-  return virtualEntrypointType
-    ? `virtual:wxt-${virtualEntrypointType}?${entrypoint.inputPath}`
-    : entrypoint.inputPath;
+
+  if (virtualEntrypointType) {
+    const moduleId: VirtualModuleId = `virtual:wxt-${virtualEntrypointType}-entrypoint`;
+    return `${moduleId}?${entrypoint.inputPath}`;
+  }
+  return entrypoint.inputPath;
 }

src/core/builders/vite/plugins/index.ts

@@ -3,7 +3,7 @@ export * from './devServerGlobals';
 export * from './download';
 export * from './multipageMove';
 export * from './unimport';
-export * from './virtualEntrypoint';
+export * from './resolveVirtualModules';
 export * from './tsconfigPaths';
 export * from './noopBackground';
 export * from './cssEntrypoints';

src/core/builders/vite/plugins/resolveVirtualModules.ts

@@ -0,0 +1,41 @@
+import { Plugin } from 'vite';
+import { ResolvedConfig } from '~/types';
+import { normalizePath } from '~/core/utils/paths';
+import {
+  VirtualModuleId,
+  virtualModuleNames,
+} from '~/core/utils/virtual-modules';
+import fs from 'fs-extra';
+import { resolve } from 'path';
+
+/**
+ * Resolve all the virtual modules to the `node_modules/wxt/dist/virtual` directory.
+ */
+export function resolveVirtualModules(config: ResolvedConfig): Plugin[] {
+  return virtualModuleNames.map((name) => {
+    const virtualId: `${VirtualModuleId}?` = `virtual:wxt-${name}?`;
+    const resolvedVirtualId = '\0' + virtualId;
+    return {
+      name: `wxt:resolve-virtual-${name}`,
+      resolveId(id) {
+        // Id doesn't start with prefix, it looks like this:
+        // /path/to/project/virtual:wxt-background?/path/to/project/entrypoints/background.ts
+        const index = id.indexOf(virtualId);
+        if (index === -1) return;
+
+        const inputPath = normalizePath(id.substring(index + virtualId.length));
+        return resolvedVirtualId + inputPath;
+      },
+      async load(id) {
+        if (!id.startsWith(resolvedVirtualId)) return;
+
+        const inputPath = id.replace(resolvedVirtualId, '');
+        const template = await fs.readFile(
+          resolve(config.wxtModuleDir, `dist/virtual/${name}.js`),
+          'utf-8',
+        );
+        return template.replace(`virtual:user-${name}`, inputPath);
+      },
+    };
+  });
+}

src/core/builders/vite/plugins/virtualEntrypoint.ts

@@ -1,39 +0,0 @@
-import { Plugin } from 'vite';
-import { ResolvedConfig, VirtualEntrypointType } from '~/types';
-import fs from 'fs-extra';
-import { resolve } from 'path';
-import { normalizePath } from '~/core/utils/paths';
-
-/**
- * Wraps a user's entrypoint with a vitual version with additional logic.
- */
-export function virtualEntrypoint(
-  type: VirtualEntrypointType,
-  config: Omit<ResolvedConfig, 'builder'>,
-): Plugin {
-  const virtualId = `virtual:wxt-${type}?`;
-  const resolvedVirtualId = `\0${virtualId}`;
-
-  return {
-    name: `wxt:virtual-entrypoint`,
-    resolveId(id) {
-      // Id doesn't start with prefix, it looks like this:
-      // /path/to/project/virtual:background?/path/to/project/entrypoints/background.ts
-      const index = id.indexOf(virtualId);
-      if (index === -1) return;
-
-      const inputPath = normalizePath(id.substring(index + virtualId.length));
-      return resolvedVirtualId + inputPath;
-    },
-    async load(id) {
-      if (!id.startsWith(resolvedVirtualId)) return;
-
-      const inputPath = id.replace(resolvedVirtualId, '');
-      const template = await fs.readFile(
-        resolve(config.wxtModuleDir, `dist/virtual/${type}-entrypoint.js`),
-        'utf-8',
-      );
-      return template.replace(`virtual:user-${type}`, inputPath);
-    },
-  };
-}

src/core/utils/__tests__/virtual-modules.test.ts

@@ -0,0 +1,20 @@
+import { describe, it } from 'vitest';
+import {
+  VirtualModuleId,
+  VirtualModuleName,
+  VirtualEntrypointType,
+  VirtualEntrypointModuleName,
+} from '../virtual-modules';
+
+describe('Virtual Modules', () => {
+  it('should resolve types to litteral values, not string', () => {
+    // @ts-expect-error
+    const _c: VirtualEntrypointType = '';
+    // @ts-expect-error
+    const _d: VirtualEntrypointModuleName = '';
+    // @ts-expect-error
+    const _b: VirtualModuleName = '';
+    // @ts-expect-error
+    const _a: VirtualModuleId = '';
+  });
+});

src/core/utils/virtual-modules.ts

@@ -0,0 +1,37 @@
+export const virtualEntrypointTypes = [
+  'content-script-main-world' as const,
+  'content-script-isolated-world' as const,
+  'background' as const,
+  'unlisted-script' as const,
+];
+export type VirtualEntrypointType = (typeof virtualEntrypointTypes)[0];
+
+/**
+ * All the names of entrypoint files in the `src/virtual/` and `dist/virtual/` directories, minus the extension.
+ */
+export const virtualEntrypointModuleNames = virtualEntrypointTypes.map(
+  (name) => `${name}-entrypoint` as const,
+);
+/**
+ * Name of entrypoint files in the `src/virtual/` and `dist/virtual/` directories, minus the extension.
+ */
+export type VirtualEntrypointModuleName =
+  (typeof virtualEntrypointModuleNames)[0];
+
+/**
+ * All the names of files in the `src/virtual/` and `dist/virtual/` directories, minus the extension.
+ */
+export const virtualModuleNames = [
+  ...virtualEntrypointModuleNames,
+  'mock-browser' as const,
+  'reload-html' as const,
+];
+/**
+ * Name of files in the `src/virtual/` and `dist/virtual/` directories, minus the extension.
+ */
+export type VirtualModuleName = (typeof virtualModuleNames)[0];
+
+/**
+ * Import alias used for importing a virtual module
+ */
+export type VirtualModuleId = `virtual:wxt-${VirtualModuleName}`;

src/types/index.ts

@@ -1103,12 +1103,6 @@ export interface ExtensionRunner {
   closeBrowser(): Promise<void>;
 }
 
-export type VirtualEntrypointType =
-  | 'content-script-main-world'
-  | 'content-script-isolated-world'
-  | 'background'
-  | 'unlisted-script';
-
 export type EslintGlobalsPropValue =
   | boolean
   | 'readonly'

src/virtual/background-entrypoint.ts

@@ -1,4 +1,4 @@
-import definition from 'virtual:user-background';
+import definition from 'virtual:user-background-entrypoint';
 import { setupWebSocket } from './utils/setup-web-socket';
 import { logger } from '../sandbox/utils/logger';
 import { browser } from 'wxt/browser';

src/virtual/content-script-isolated-world-entrypoint.ts

@@ -1,4 +1,4 @@
-import definition from 'virtual:user-content-script-isolated-world';
+import definition from 'virtual:user-content-script-isolated-world-entrypoint';
 import { logger } from '../sandbox/utils/logger';
 import { ContentScriptContext } from 'wxt/client';
 

src/virtual/content-script-main-world-entrypoint.ts

@@ -1,4 +1,4 @@
-import definition from 'virtual:user-content-script-main-world';
+import definition from 'virtual:user-content-script-main-world-entrypoint';
 import { logger } from '../sandbox/utils/logger';
 
 (async () => {

src/virtual/unlisted-script-entrypoint.ts

@@ -1,4 +1,4 @@
-import definition from 'virtual:user-unlisted-script';
+import definition from 'virtual:user-unlisted-script-entrypoint';
 import { logger } from '../sandbox/utils/logger';
 
 (async () => {

src/virtual/virtual-module-globals.d.ts

@@ -1,11 +1,11 @@
 // Types required to make the virtual modules happy.
 
-declare module 'virtual:user-background' {
+declare module 'virtual:user-background-entrypoint' {
   const definition: { main: () => void };
   export default definition;
 }
 
-declare module 'virtual:user-content-script-isolated-world' {
+declare module 'virtual:user-content-script-isolated-world-entrypoint' {
   const definition: {
     main: (
       ctx: import('wxt/client').ContentScriptContext,
@@ -14,12 +14,12 @@ declare module 'virtual:user-content-script-isolated-world' {
   export default definition;
 }
 
-declare module 'virtual:user-content-script-main-world' {
+declare module 'virtual:user-content-script-main-world-entrypoint' {
   const definition: { main: () => void | Promise<void> };
   export default definition;
 }
 
-declare module 'virtual:user-unlisted-script' {
+declare module 'virtual:user-unlisted-script-entrypoint' {
   const definition: { main: () => void | Promise<void> };
   export default definition;
 }