feat: Add globalName entrypoint option.

packages/wxt/e2e/tests/modules.test.ts

@@ -1,6 +1,6 @@
 import { describe, it, expect, vi } from 'vitest';
 import { TestProject } from '../utils';
-import type { GenericEntrypoint, InlineConfig } from '../../src';
+import type { InlineConfig, UnlistedScriptEntrypoint } from '../../src';
 import { readFile } from 'fs-extra';
 import { normalizePath } from '../../src';
 
@@ -49,7 +49,7 @@ describe('Module Helpers', () => {
         'export default defineBackground(() => {})',
       );
 
-      const entrypoint: GenericEntrypoint = {
+      const entrypoint: UnlistedScriptEntrypoint = {
         type: 'unlisted-script',
         inputPath: project.resolvePath('modules/test/injected.ts'),
         name: 'injected',

packages/wxt/e2e/tests/output-structure.test.ts

@@ -459,4 +459,104 @@ describe('Output Directory Structure', () => {
       "
     `);
   });
+
+  describe('globalName option', () => {
+    it('generates an IIFE with a default name', async () => {
+      const project = new TestProject();
+      project.addFile(
+        'entrypoints/content.js',
+        `export default defineContentScript({
+          matches: ["*://*/*"],
+          main() {},
+        })`,
+      );
+
+      await project.build({ vite: () => ({ build: { minify: false } }) });
+
+      const output = await project.serializeFile(
+        '.output/chrome-mv3/content-scripts/content.js',
+      );
+      expect(output).toMatch(/^var content\s?=[\s\S]*^content;$/gm);
+    });
+
+    it('generates an IIFE with a specific name', async () => {
+      const project = new TestProject();
+      project.addFile(
+        'entrypoints/content.js',
+        `export default defineContentScript({
+          globalName: "MyContentScript",
+          matches: ["*://*/*"],
+          main() {},
+        })`,
+      );
+
+      await project.build({ vite: () => ({ build: { minify: false } }) });
+
+      const output = await project.serializeFile(
+        '.output/chrome-mv3/content-scripts/content.js',
+      );
+      expect(output).toMatch(
+        /^var MyContentScript =[\s\S]*^MyContentScript;$/gm,
+      );
+    });
+
+    it('generates an IIFE with a specific name provided by a function', async () => {
+      const project = new TestProject();
+      project.addFile(
+        'entrypoints/content.js',
+        `export default defineContentScript({
+          globalName: () => "MyContentScript",
+          matches: ["*://*/*"],
+          main() {},
+        })`,
+      );
+
+      await project.build({ vite: () => ({ build: { minify: false } }) });
+
+      const output = await project.serializeFile(
+        '.output/chrome-mv3/content-scripts/content.js',
+      );
+      expect(output).toMatch(
+        /^var MyContentScript =[\s\S]*^MyContentScript;$/gm,
+      );
+    });
+
+    it('generates an anonymous IIFE when not minified', async () => {
+      const project = new TestProject();
+      project.addFile(
+        'entrypoints/content.js',
+        `export default defineContentScript({
+          globalName: false,
+          matches: ["*://*/*"],
+          main() {},
+        })`,
+      );
+
+      await project.build({ vite: () => ({ build: { minify: false } }) });
+
+      const output = await project.serializeFile(
+        '.output/chrome-mv3/content-scripts/content.js',
+      );
+      expect(output).toMatch(/^\(function\(\) {[\s\S]*^}\)\(\);$/gm);
+    });
+
+    it('generates an anonymous IIFE when minified', async () => {
+      const project = new TestProject();
+      project.addFile(
+        'entrypoints/content.js',
+        `export default defineContentScript({
+          globalName: false,
+          matches: ["*://*/*"],
+          main() {},
+        })`,
+      );
+
+      await project.build({ vite: () => ({ build: { minify: true } }) });
+
+      const output = await project.serializeFile(
+        '.output/chrome-mv3/content-scripts/content.js',
+      );
+      expect(output).toMatch(/^\(function\(\){[\s\S]*}\)\(\);$/gm);
+    });
+  });
 });

packages/wxt/src/core/builders/vite/index.ts

@@ -109,7 +109,7 @@ export async function createViteBuilder(
     const plugins: NonNullable<vite.UserConfig['plugins']> = [
       wxtPlugins.entrypointGroupGlobals(entrypoint),
     ];
-    const iifeReturnValueName = safeVarName(entrypoint.name);
+    let iifeReturnValueName = safeVarName(entrypoint.name);
 
     if (
       entrypoint.type === 'content-script-style' ||
@@ -122,7 +122,17 @@ export async function createViteBuilder(
       entrypoint.type === 'content-script' ||
       entrypoint.type === 'unlisted-script'
     ) {
-      plugins.push(wxtPlugins.iifeFooter(iifeReturnValueName));
+      if (typeof entrypoint.options.globalName === 'string') {
+        iifeReturnValueName = entrypoint.options.globalName;
+      } else if (typeof entrypoint.options.globalName === 'function') {
+        iifeReturnValueName = entrypoint.options.globalName(entrypoint);
+      }
+
+      if (entrypoint.options.globalName === false) {
+        plugins.push(wxtPlugins.iifeAnonymous(iifeReturnValueName));
+      } else {
+        plugins.push(wxtPlugins.iifeFooter(iifeReturnValueName));
+      }
     }
 
     return {

packages/wxt/src/core/builders/vite/plugins/iifeAnonymous.ts

@@ -0,0 +1,17 @@
+import type { Plugin } from 'vite';
+
+export function iifeAnonymous(iifeReturnValueName: string): Plugin {
+  return {
+    name: 'wxt:iife-anonymous',
+    generateBundle(_, bundle) {
+      for (const chunk of Object.values(bundle)) {
+        if (chunk.type === 'chunk' && chunk.isEntry) {
+          const namedIIFEPrefix = new RegExp(
+            `^var ${iifeReturnValueName}\\s*=\\s*(\\(function)`,
+          );
+          chunk.code = chunk.code.replace(namedIIFEPrefix, '$1');
+        }
+      }
+    },
+  };
+}

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

@@ -14,3 +14,4 @@ export * from './removeEntrypointMainFunction';
 export * from './wxtPluginLoader';
 export * from './resolveAppConfig';
 export * from './iifeFooter';
+export * from './iifeAnonymous';

packages/wxt/src/core/utils/building/find-entrypoints.ts

@@ -10,6 +10,7 @@ import {
   SidepanelEntrypoint,
   MainWorldContentScriptEntrypointOptions,
   IsolatedWorldContentScriptEntrypointOptions,
+  UnlistedScriptEntrypoint,
 } from '../../../types';
 import fs from 'fs-extra';
 import { minimatch } from 'minimatch';
@@ -319,7 +320,7 @@ async function getUnlistedPageEntrypoint(
 async function getUnlistedScriptEntrypoint(
   { inputPath, name }: EntrypointInfo,
   options: Record<string, any>,
-): Promise<GenericEntrypoint> {
+): Promise<UnlistedScriptEntrypoint> {
   return {
     type: 'unlisted-script',
     name,

packages/wxt/src/core/utils/testing/fake-objects.ts

@@ -21,6 +21,7 @@ import {
   Wxt,
   SidepanelEntrypoint,
   BaseEntrypoint,
+  UnlistedScriptEntrypoint,
 } from '../../../types';
 import { mock } from 'vitest-mock-extended';
 import { vi } from 'vitest';
@@ -99,7 +100,7 @@ export const fakeBackgroundEntrypoint = fakeObjectCreator<BackgroundEntrypoint>(
 );
 
 export const fakeUnlistedScriptEntrypoint =
-  fakeObjectCreator<GenericEntrypoint>(() => ({
+  fakeObjectCreator<UnlistedScriptEntrypoint>(() => ({
     type: 'unlisted-script',
     inputPath: fakeFile('src'),
     name: faker.string.alpha(),
@@ -186,7 +187,6 @@ export const fakeGenericEntrypoint = fakeObjectCreator<GenericEntrypoint>(
       'newtab',
       'devtools',
       'unlisted-page',
-      'unlisted-script',
     ]),
     inputPath: fakeFile('src'),
     name: faker.string.alpha(),

packages/wxt/src/types.ts

@@ -566,7 +566,28 @@ export interface BackgroundEntrypointOptions extends BaseEntrypointOptions {
   type?: PerBrowserOption<'module'>;
 }
 
-export interface BaseContentScriptEntrypointOptions extends BaseEntrypointOptions {
+export interface BaseScriptEntrypointOptions extends BaseEntrypointOptions {
+  /**
+   * The variable name for the IIFE in the output bundle.
+   *
+   * This option is relevant for scripts inserted into the page context where the default IIFE
+   * variable name may conflict with an existing variable on the target page. This applies to content
+   * scripts with world=MAIN, and others, such as unlisted scripts, that could be dynamically injected
+   * into the page with a <script> tag.
+   *
+   * Available options:
+   * - `true`: automatically generate a name for the IIFE based on the entrypoint name
+   * - `false`: Output the IIFE without a variable name, making it anonymous. This is the safest option
+   *  to avoid conflicts with existing variables on the page. This will become the default in a future version of WXT.
+   * - `string`: Use the provided string as the global variable name.
+   * - `function`: A function that receives the entrypoint and returns a string to use as the variable name.
+   *
+   * @default true
+   */
+  globalName?: string | boolean | ((entrypoint: Entrypoint) => string);
+}
+
+export interface BaseContentScriptEntrypointOptions extends BaseScriptEntrypointOptions {
   matches?: PerBrowserOption<NonNullable<ManifestContentScript['matches']>>;
   /**
    * See https://developer.chrome.com/docs/extensions/mv3/content_scripts/
@@ -749,12 +770,16 @@ export interface GenericEntrypoint extends BaseEntrypoint {
     | 'newtab'
     | 'devtools'
     | 'unlisted-page'
-    | 'unlisted-script'
     | 'unlisted-style'
     | 'content-script-style';
   options: ResolvedPerBrowserOptions<BaseEntrypointOptions>;
 }
 
+export interface UnlistedScriptEntrypoint extends BaseEntrypoint {
+  type: 'unlisted-script';
+  options: ResolvedPerBrowserOptions<BaseScriptEntrypointOptions>;
+}
+
 export interface BackgroundEntrypoint extends BaseEntrypoint {
   type: 'background';
   options: ResolvedPerBrowserOptions<BackgroundEntrypointOptions>;
@@ -786,6 +811,7 @@ export interface SidepanelEntrypoint extends BaseEntrypoint {
 export type Entrypoint =
   | GenericEntrypoint
   | BackgroundEntrypoint
+  | UnlistedScriptEntrypoint
   | ContentScriptEntrypoint
   | PopupEntrypoint
   | OptionsEntrypoint
@@ -835,7 +861,7 @@ export interface BackgroundDefinition extends BackgroundEntrypointOptions {
   main(): void;
 }
 
-export interface UnlistedScriptDefinition extends BaseEntrypointOptions {
+export interface UnlistedScriptDefinition extends BaseScriptEntrypointOptions {
   /**
    * Main function executed when the unlisted script is ran.
    *